State of California
AIR RESOURCES BOARD

Staff Report for the Proposed 
Suggested Control Measure
for Architectural Coatings

Volume II:
Technical Support Document

VI.

DESCRIPTION AND TECHNICAL ASSESSMENT
OF THE COATING CATEGORIES

TABLE OF CONTENTS FOR CHAPTER VI - SECTION A

For SECTIONS B AND C PLEASE CLICK HERE

A. COATING CATEGORIES FOR WHICH WE ARE PROPOSING NEW VOC LIMITS

We are proposing new VOC limits for the following 31 coating categories that are generally consistent with the interim VOC limits adopted in recent amendments to the South Coast AQMD's Rule 1113 (with the exception of antenna coatings, antifouling coatings, bituminous roof coatings, clear brushing lacquers, floor coatings, flow coatings, high-temperature coatings, non-flat high gloss coatings, pre-treatment wash primers, swimming pool repair and maintenance coatings, and waterproofing sealers). However, in many cases, the proposed limits are lower than the existing VOC limits in other district rules in California. Therefore, the discussions of these coating categories are more detailed than those for the other categories. The discussions for each of these coating categories include:

1. product category description;
2. information on product use and marketing;
3. information on the existing product formulations;
4. discussion of the proposed VOC limit, our rationale for the proposed limit, and the options for compliance; and
5. if applicable, a discussion of the issues associated with the proposed VOC limit, as raised by the affected industry. After the Flat and Non-flat categories, the product categories are in alphabetical order.

Product Category Description:

Flat coatings are widely used on both interior and exterior surfaces of residential and commercial buildings. Flat coatings leave a matte finish, with no gloss or shine. They are defined as having a gloss of less than 15 on an 85^o meter or less than 5 on a 60^o meter. The flat finish tends to minimize surface irregularities and imperfections.

Table VI-1 below summarizes our estimate of sales and VOC emissions from the flat coatings category based on ARB survey results. The ARB survey (ARB, 1999) shows that flat coatings represent the largest coating category with regard to both sales volume and VOC emission levels. In 1996 (the year surveyed), approximately 32 million gallons of flat coatings were used in California. This represents about 36 percent of the total California sales volume of architectural coatings in 1996. The VOC emissions from flat coatings in California, excluding those emissions that occur in the South Coast AQMD, are about 8.0 tons per day (TPD). VOC emissions from flat coatings represent approximately 15 percent of the total emissions from architectural coatings. Because most of the products sold are water-based, most of the emissions are from water-based products, even though these products have a lower sales-weighted average VOC content than solvent-based products.

 

Table VI-1 Flat Coatings*
	Number of Products	Category Sales (gallons/year)	Sales-Weighted Average VOC (grams/liter)**	VOC Emissions (excluding South Coast AQMD) (tons/day)
Solvent-Based	56	27,873	373	0.06
Water-Based	2,299	31,800,868	98	7.94
Total	2,355	31,828,705	98	8.00

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

Typically, flat coatings can be brushed, rolled, or sprayed on the surface to be painted. Flat coatings make up approximately 80 to 90 percent of the total coatings used for residential applications (South Coast AQMD, 1996). "Do-it-yourselfers" and paint contractors can purchase flat coatings at outlets including hardware stores, home supply stores, and retail paint stores. Flat coatings are used on interior walls and ceilings, and are typically used to paint living rooms, dining rooms, bedrooms, and halls. Flat coatings are also used on exterior walls and overhangs. With proper surface cleaning and priming (if necessary), flat coatings can be used on a large variety of interior and exterior substrates including drywall, plaster, wallpaper, brick, concrete block, wood siding, vinyl siding, aluminum siding, and stucco. Because most flat coatings are water-based, soap-and-water cleanup is typical. Most flat coatings (about 97 percent) are sold in size units greater than one liter (ARB, 1999).

The 1998 ARB survey showed that about 41 percent of the flat coatings sold in 1996 were formulated for interior applications, 30 percent for exterior applications, and 29 percent were formulated for both interior and exterior applications (ARB, 1999).

For marketing their products, some manufacturers of "zero VOC" flat coatings emphasize the health benefits of using such coatings versus conventional coatings. The benefits include the low-to-minimal odor of zero VOC coatings and the reduced chemical exposures from the use of such coatings. Because of those features, manufacturers of zero VOC coatings emphasize the coatings' suitability for use in enclosed centrally-ventilated buildings (e.g. schools, office buildings, and hospitals), rooms that need to be occupied soon after painting (e.g. restaurants, hotel rooms), and residences.

Product Formulation:
As discussed earlier, most flat coatings are water-based. The 1998 ARB survey (which represents 1996 sales as reported) shows that water-based flat coatings represent over 99 percent of the flat coatings market. Solvent-based flat coatings represent 0.1 percent of the market and generally have VOC levels greater than 250 g/l, the VOC limit for flat coatings currently in effect for those California air pollution control districts that have architectural coatings rules. The volume of solvent-based flat coatings sold has decreased approximately 54 percent since the 1993 ARB survey of architectural coatings (which reflected 1990 sales), while overall sales of flat coatings has remained about the same. The overall sales-weighted average VOC level for flat coatings has decreased 7 percent since the 1993 ARB survey (ARB, 1999).

Generally, the type of binder used in a formulation has a large influence on the amount of VOC needed. Binders serve to hold the paint together in a film and to provide adhesion to the substrate. The binder in water-based flat coatings, which comprise the majority of flat coatings, is typically a dispersion of synthetic resin particles, called latex. Thus, these types of coatings are commonly called latex coatings. A wide variety of synthetic polymers are used as binders in latex coatings. Two common latex binders are acrylic and vinyl-acrylic resins. The solvent-based coatings in this category are commonly formulated using alkyd resins as binders.

The VOCs in water-based coatings perform one or more of the following functions: binder coalescing aid, polymer plasticizer, freeze/thaw stabilizer, defoamer, and carriers for other additives such as colorants, thickening agents, surfactants, and biocides. The largest contributors of VOCs in latex coatings are glycols, added mainly to provide freeze/thaw resistance, and coalescing solvents such as 2,2,4-trimethyl-1,3-pentanediol isobutyrate (Texanol®), to allow the latex particles to come together to form a film (Klein, 1993). Generally, so called "zero VOC" coatings contain very small amounts of VOCs. Lower-VOC coatings tend to be formulated using binders that require less coalescing solvent and/or are formulated using less VOCs for freeze/thaw stabilization (Klein, 1993; Currie, 1993).
 

Proposed VOC Limit and Basis for Recommendation:
We recommend a 100 g/l VOC limit for flat coatings, effective January 1, 2003. The proposed VOC limit is technologically and commercially feasible by January 1, 2003, based on our review of ARB survey data on marketshares, product information from manufacturers, and other information as discussed below. The proposed VOC limit is lower than the national limit recently promulgated by the United States Environmental Protection Agency (U.S. EPA) for this category. The U.S. EPA divides flat coatings into interior and exterior categories, but the same VOC limit, 250 g/l, applies to both (U.S. EPA, 1998). In California, the 1989 SCM for architectural coatings recommended a 250 g/l VOC limit for flat coatings (ARB, 1989); this is the most common limit currently in effect for those California air pollution control districts that have architectural coatings rules. In 1996, the South Coast AQMD adopted a 100 g/l limit for flat coatings that will become effective July 1, 2001, and also adopted a 50 g/l limit that will become effective July 1, 2008. Our recommended limit is consistent with the interim limit adopted by the South Coast AQMD.

As shown in Table VI-2, the 1998 ARB survey found that about half of the marketshare of flat coatings complies with the proposed VOC limit. Nearly 1,100 products of the approximately 2,400 products reported already comply with the proposed limit. Of the 45 companies that reported in this category, 36 offered flat coatings that comply with the proposed limit. Products with a VOC content equal to or lower than 50 g/l represent about 18 percent of the market, and products with a VOC content equal to or lower than 150 g/l represent 88 percent of the market. (ARB, 1999).

The table below also shows that VOC emission reductions in the non-South Coast AQMD portion of California would be approximately 1.4 TPD, on an annual average basis, from implementing the proposed limit of 100 g/l.

* Based on ARB's 1998 Architectural and Industrial Maintenance Coatings Survey (ARB, 1999).

Considering flat coatings formulated for interior and exterior use separately, the 1998 ARB survey indicates that 69 percent (550 products) of the volume of interior flat coatings sold comply with the proposed limit, 42 percent (276 products) of the volume of exterior flat coatings sold comply, and 27 percent (143 products) of the volume of coatings sold for both interior and exterior use comply (ARB, 1999).

The high marketshares that already comply with the proposed limit demonstrate widespread use of existing low-VOC technology for formulating flat coatings. While almost all flat coatings are currently water-based latex coatings, the proposed limit would require more water-based products to be formulated using lower-VOC technology. As discussed above, the primary sources of VOCs in latex coatings are coalescing solvents and VOCs (glycols) added mainly to provide freeze/thaw resistance. We expect that product reformulation to meet the proposed limit would involve switching to a binder (or blend of binders) that requires less coalescing solvent and/or reducing the amount of glycol that is added to provide freeze/thaw stability (Klein, 1993; Currie, 1993).

Of note is that most solvent-based flat coatings used in districts without architectural coatings rules do not meet the 250 g/l limit currently in place in district architectural coatings rules. Such solvent-based coatings will at a minimum have to be reformulated (likely to water-based) to meet the national rule limit of 250 g/l in those California districts that do not adopt architectural coatings rules.

Independent Product Tests

Consumers Union, an independent, nonprofit organization, recently reported on tests it performed on interior and exterior paints. Tests were performed on 14 brands of interior flat paints marketed as higher-grade paints. For each brand, three colors that represent the basic tint bases were tested. Several flat paints with VOC levels below 100 g/l were included in the tests. The paints were tested for hiding ability and resistance to scrubbing, staining, blocking, fading, and mildew. All the interior flat paints tested performed well, rating "good" or better in overall scores. One complying flat paint, Pittsburgh Manor Hall, was included as one of the five paints recommended as "best of the flats" and received the second highest overall score
(Consumer Reports, 2000).

Consumers Union also tested 16 brands of exterior latex flat paints (three colors for each brand) purchased mostly from the northeastern United States. ARB staff was able to ascertain that one flat paint tested complies with the proposed 100 g/l limit. The paints were applied to Southern yellow pine, a type of wood prone to cracking, and were exposed to the weather in New York and Florida for nearly two years. Periodic assessments were made for signs of cracking, color change, dirt buildup, mildew growth, and other problems. The investigators also tested how well the paints adhered to a chalky surface. Based on the test results, four flat paints received a recommendation from Consumers Union. Those recommended paints included Glidden Dulux Endurance flat, which, with the exception of its accent tint base, complies with the proposed VOC limit (Consumer Reports, 1999).

Product information from manufacturers

Product information sheets published by coatings manufacturers indicate that a wide variety of flat coatings that meet the proposed VOC limit are available that possess performance characteristics similar to higher-VOC coatings. At the end of the discussion of this category are tables of information about specific products that meet the proposed VOC limit and, for comparison, products that exceed the proposed limit. We identified specific products with a VOC content of 100 g/l or less offered by Behr, Devoe, Dunn Edwards, Frazee, ICI-Dulux, Rodda Paint, Sherwin Williams, and Tru-Test. A list of performance characteristics compiled from product information sheets for interior and exterior flat coatings with VOC levels of 100 g/l or less is presented below. Please note that not all flat coatings with VOC levels at or below 100 g/l possess all of the characteristics listed below:

Interior flat coatings

Exterior flat coatings

good quality, high quality, premium quality, top of the line quality  good to excellent hiding qualities, good dry hiding durable crack-resistant long-lasting finish excellent adhesion excellent color and sheen uniformity non-yellowing good to excellent touch-up properties good stain resistance washable to extremely washable, durable, long-lasting protection easy application excellent freeze-thaw resistance high film build without sags or runs

quality product, top of the line, premium quality long-lasting durability, durable and tough exceptional coverage excellent adhesion low temperature application to 35o F maximum protection against UV color fade, efflorescence, water intrusion, and film failure, fade and chalk resistant resists blistering, peeling, and flaking easy application very good to excellent touch-up good hide exceptional mildew resistance

Issues:

1. Issue:
The flat coatings category covers a broad range of products. The ARB should consider subcategorizing the flat coatings category to allow for a higher VOC limit for special use, high performance products. A specific suggestion is to split the flat coatings category into interior and exterior subcategories with different VOC limits for each.

Response: The information we reviewed does not substantiate the need to subcategorize the flat coatings category. Our survey of product information published by coating manufacturers indicates that a wide variety of product types in the flat coatings category already comply with the proposed limit. This includes coatings formulated specifically for acoustic ceilings, coatings formulated for contractors (which emphasize features such as ease and speed of application, hiding properties, and touch-up properties), texture coatings, high-build coatings, coatings designed for low temperature application, and premium quality coatings.

As discussed above, information on marketshares obtained from the 1999 ARB survey indicates that a considerable portion of interior and exterior flat coatings already comply with the proposed limit. Our survey of product information and independent test results show that a variety of performance characteristics comparable to those of higher VOC products have been achieved for both interior and exterior flat coatings with VOC levels at or below 100 g/l.

2. Issue:
The 100 g/l limit for flat coatings will allow the sale of medium quality coatings, but consumers will not be able to purchase high quality flats that will stand up to repeated washings or have good exterior durability. Application properties at lower temperatures will be compromised, as will freeze-thaw resistance.

Response: Product information from coating manufacturers and independent test results indicate that a variety of manufacturers have been able to use available technology to achieve desirable properties for flat coatings with VOC levels at or below 100 g/l. Our survey of product information indicates that there are a number of existing interior and exterior coatings that meet the proposed limit that are marketed as premium quality coatings. Further, the product information and test results indicate that there are complying coatings with excellent scrub resistance and durability. Also, there are complying products that allow for low temperature application and products with good freeze-thaw resistance.

3. Issue:
It is premature to adopt South Coast AQMD's interim flat limit when the District committed in Rule 1113 to do a technical assessment prior to its 2001 implementation date.

Response: South Coast AQMD Rule 1113 requires the District to perform the first technology assessment on flat coatings by July 1, 2000, a year before the 100 g/l limit is to take effect in that district. We expect that the South Coast AQMD's assessment will largely consider the same types of information that we considered in our assessment, i.e. information obtained in ARB's 1998 survey, information on product tests, and product information from coating manufacturers. We will monitor the South Coast AQMD's work in this area, and if their assessment indicates a need to reconsider the 100 g/l limit for flat coatings, there will be sufficient time for the other California districts to make any necessary rule changes before the recommended effective date.

FLAT COATINGS
LESS THAN OR EQUAL TO 100 g/l
Product Name and Brand	VOC Content g/l	Type1	Information from Manufacturer’s Product Sheets
Behr Premium Plus Interior Flat Smooth Wall Texture Paint	25	I	Durable, crack resistant, long lasting finish, excellent adhesion
Benjamin Moore Pristine Eco Spec Interior Latex Flat 219	0	I	Washable, spatter-resistant, high hiding, excellent touch-up, uniform finish
DeVoe Paint DE-VO-KO Flat Interior Latex Wall Paint #378XX	61	I	Good quality, economy and speed of application, excellent color & sheen uniformity, good dry hiding, non-yellowing
DeVoe Paint DE-VO-PRO Flat Interior Latex Wall Paint #534XX	31	I	Good hiding, low odor, good touch-up
DeVoe Paint Wonder-Hide Flat Interior Latex Wall Paint #519XX	33	I	High quality, good hiding, good touch-up,  non-yellowing, good washability, good scrubability, easy application, excellent color & sheen uniformity, excellent freeze-thaw resistance, excellent adhesion
DeVoe Paint SPRA-MAX 40 Flat Interior High Build Latex Coating #45XX	90	I	High quality, high film build for all types of interior surfaces, film thickness to 20 mils dry are easily obtained without sags or runs, durable, washable surface
Dunn Edwards Acoustikote Interior Acoustic Paint	0	I	High-hiding, sprays easily, finish does not affect sound-deadening qualities of acoustical surfaces
Dunn Edwards Decovel Interior Velvet Flat Wall Paint W 401	65	I	Premium flat wall paint, exceptional hide, good stain resistance & washability, easy to apply, designed to provide long lasting protection for interior walls, ceilings & other properly prepared & primed surfaces
Dunn Edwards Interior Maintenance Latex Flat Paint	65	I	Heavy-bodied, superior hiding power, applies very easily, touches-up well
Dunn Edwards Quik-Wall Interior Latex Flat Wall Finish	65	I	Heavy-bodied, excellent hide, touches up very well
Dunn Edwards Sierra Low Odor/Zero VOC Flat Wall Finish W 501	0	I	Exceptional hide & applies easily
Dunn Edwards Tuffwall Interior Latex Flat Enamel	95	I	Tough, durable finish that is extremely washable, excellent touch-up qualities, very good hiding power
Dunn Edwards Walltone Interior Flat Wall Paint	45	I	Durable, easy touch-up, good hide
Dunn Edwards Arizona Exterior Latex Flat Finish	65	I/E	Good hide, very good touch-up
Dunn Edwards Prokote Plus Exterior Flat Paint for New Construction	70	E	Excellent touch-up qualities, durable, good hide
Dunn Edwards Evershield 100% Acrylic Wood & Masonry Flat W 701	85	E	Top of the line, advanced technology & premium ingredients provide unparalleled performance, long-lasting durability, exceptional coverage & excellent adhesion, provides maximum protection against UV color fade efflorescence, water intrusion & film failure (grain crack, peeling & blistering)
Frazee Majestic Interior Acrylic Copolymer Velvet Flat Finish	89	I	Top of the line quality, test results:  resistance to abrasion – Pass, resistance to blocking - pass, resistance to washing - pass, resistance to yellowing – pass, resistance to 1500-2000 scrub cycles – pass
Frazee Acoustic Ceiling Paint Interior Acoustic Flat Latex Finish	93	I	Top of the line quality, high hide, doesn’t affect sound deadening properties of substrate
Frazee Speedwall Plus Interior Vinyl-Acrylic Flat Finish	89	I	Top of the line commercial quality, ease of application, test results:  resistance to abrasion - pass, resistance to blocking – pass, resistance to washing - pass, resistance to yellowing - pass, resistance to 1500 - 2000 scrub cycles – pass
Frazee Speedwall Interior Vinyl-Acrylic Flat Finish	72	I	Top of the line commercial quality, maximum hiding
Frazee Craftsman Heavy Duty Interior Vinyl Flat Finish	77	I	Top of the line commercial quality, excellent hiding qualities
Frazee Envirokote Interior Low Odor Zero VOC Flat Finish	0	I	Top of the line quality, test results: - resistance to abrasion - pass, resistance to blocking - pass, resistance to washing - pass, resistance to yellowing - pass, resistance to 500 - 600 scrub cycles – pass
ICI-Dulux Decra-Shield Exterior 100% Acrylic Finish	0	E	Premium quality, exceptional mildew resistance, low temperature application to 35°F, good resistance to early moisture exposure, durable & tough, fade & chalk resistant, excellent adhesion, resists blistering, peeling & flaking, easy application
ICI-Dulux Lifemaster 2000 Interior Flat Finish LM 9100	0	I	Professional best, exceptional hiding, excellent touch-up properties, washable, durable
ICI-Dulux Professional Velvet Matte Interior Flat Latex Wall & Trim Finish	85	I	Premium quality, excellent touch-up, coverage & application properties, durable & washable
ICI-Dulux Ultra Velvet Sheen Interior Flat Latex Wall & Trim Finish	92	I	Excellent hiding, highest quality premium flat latex, excellent coverage & application properties, good burnish resistance, durable, wear resistant, very good touch-up, excellent scrub resistance, very good washability
ICI-Dulux Ultra-Wall Latex Flat Interior Wall Paint	50	I	Professional quality, high hiding, excellent touch-up, uniform flat finish, non-yellowing
ICI-Dulux Speed-Wall Latex Matte Flat Interior Wall Paint	33	I	Excellent dry hide, uniform flat finish, excellent touch-up properties
ICI-Dulux Speed-Wall Latex Flat Interior Wall Paint	18	I	Excellent dry hide, uniform flat finish, good touch-up properties
ICI-Dulux Ultra-Hide Latex Flat Interior Wall Paint "The Workhorse"	98	I	Professional best "workhorse," high hiding, excellent touch-up, uniform finish, washable, non-yellowing, easy application, excellent hiding & flexibility
ICI-Dulux Ultra-Hide High-Build Latex Flat Interior Primer/Finish	46	I	High-build, excellent touch-up properties,
ICI-Dulux Ultra-Hide Build-Dur Spray Latex Flat Interior Primer/Finish	83	I	High-build without running or sagging
ICI-Dulux Speed-Cote Exterior Latex Flat Masonry Finish	22	E	Uniform flat finish, easy application
ICI-Dulux Ultra Hide, Interior/Exterior High-Build Acrylic Latex Texture Coating	88	I/E	Premium quality, provides a uniform texture on rough or irregular surfaces
Rodda Paint AC-911 Exterior Latex House Paint	96	E	Uniform finish, smooth even finish, very good resistance to moisture
Rodda Paint Krillicon Exterior Flat Paint	85	E	Very good resistance to moisture – masonry paint
Rodda Paint Ezee Coat Flat Wall Paint	67	I	High hiding, economical, excellent touch-up characteristics, good resistance to moisture
Rodda Paint Horizon Clean Air Select	0	I	Washable, uniform, durable, easy application properties, excellent resistance to moisture
Rodda Terra Solid Color Latex Flat	76	E	For rough wood surfaces where the ultimate in color retention & durability is desired, excellent resistance to moisture
Sherwin Williams Health Spec Low Odor Latex Interior Flat	2.4-6	I	Provides the durability expected from a flat wall paint without the odor associated with typical latex paints; 1300 scrubs
Sherwin Williams Style Perfect Interior Flat Latex Ceiling Paint	51	I	No specific performance information provided
Sherwin Williams Style Perfect Interior Latex Flat	36-48	I	Fade resistant, easy to apply, resists yellowing, easy clean-up
Sherwin Williams ProMar 700 Interior Latex Flat Wall Paint	48-60	I	No specific performance information provided
Sherwin Willaims ProMar 400 Interior Latex Flat	48-84	I	Durable, quality vinyl acrylic paint
Sherwin Williams ProMar 200 Interior Latex Flat	48-84	I	Finest quality product designed for the professional
Tru-Test Contractor’s Latex Flat Wall Paint GF-Line	<100	E	No specific performance information provided
ACE Quality Paints 7* Flat Latex Wall Paint	198	I	15 year durability, scrubbable, low spatter, non-yellowing, colorfast, stain resistant
ACE Quality Paints 7* Flat Latex Ceiling White	213	I	Low spatter, non-yellowing, colorfast, stain resistant, finish reduces reflection and glare
ACE Quality Paints 5* Flat Latex Wall Paint	215	I	Washable, easy application, non-yellowing, colorfast, spot resistant
ACE Quality Paints 5* Flat Latex Ceiling Paint	175	I	Washable, easy application, non-yellowing, colorfast, spot resistant
ACE Quality Paints 7* Acrylic Latex House Paint	143	E	15 year durability, no chalk washdown, mildew resistant, non-yellowing, washable, stain resistant
ACE Quality Paints 5* Acrylic Latex House Paint	143	E	Stain resistant, no chalk washdown, non-yellowing, washable
ACE Quality Paints Pro High Hiding Flat Latex Wall Paint	141	I	Good touch up
AFM Safecoat Interior Flat	102	I	Premium quality, superior hiding properties, durable finish
Devoe Paint Velour Flat Interior Alkyd Wall Paint	372	I	Easy application, excellent hiding, excellent durability, good washability
Devoe Paint Wonder Tones Flat Interior Latex Wall Paint	203	I	Premium quality, durable, excellent hiding, non-yellowing, resists staining, highly washable, excellent touch-up, excellent spatter resistance
Devoe Paint Ceiling White Flat Interior Latex Paint	125	I	Good hiding, easy application, excellent spatter resistance, non-yellowing
Devoe Paint SPRA-MAX-12 Flat Interior Medium Build Latex Coating	158	I	Excellent hiding, fast application, excellent washability
Devoe Paint Wonder-Speed Flat Interior Latex Wall Paint	219	I	Professional best, good hiding, excellent tuoch-up, non-yellowing, washable, easy application
Dunn Edwards Acri-Flat 100% Acrylic Exterior Wood Stain & Masonry Flat Paint	120	E	Easy to apply, excellent color retention, good crack resistance, long-term exterior durability
Dunn Edwards Endurawall Elastomeric Wall Coating Smooth	110	E	Exceptional flexibility, provides superior protection against wind-driven rain and moisture by bridging cracks, outstanding elastic recovery and resilience even under conditions of extreme cold or heat, outstanding resistance to UV light and dirt pick up, easy touch-up
Dunn Edwards Suprema Interior Low Sheen Wall Paint	135	I	Premium quality, tough washable finish, outstanding stain resistance, durability and hide
Frazee Velvin Interior Acrylic Copolymer Flat Finish	112	I	Top of the line quality, test results: resistance to abrasion – pass, resistance to blocking – pass, resistance to washing – pass, resistance to yellowing – pass, resistance to 600-800 scrub cycles – pass
Frazee Luxwall Heavy-Duty Interior Vinyl-Acrylic Flat Finish	165	I	Top of the line commercial quality, outstanding hiding power
Frazee Luxwall Ready-To-Use Interior Vinyl-Acrylic Flat Finish	165	I	Top of the line commercial quality, outstanding hiding power
Frazee Versa-Tex Interior/Exterior Acrylic Copolymer Flat Finish	126	I/E	Fine quality, tough, blister resistant, good adhesion and weather resistance
Frazee Duratec II 100% Acrylic Exterior Flat	102	E	Excellent quality, excellent adhesion and weather resistance
Frazee Acri-Tec Exterior Acrylic Copolymer Flat Finish	105	E	Commercial quality, assures good fade/weather resistance, test results: resistance to blocking – pass, resistance to chalking – pass, resistance to fading – pass, resistance to grain cracking – pass, resistance to UV rays – pass
Frazee Acri-Kote Exterior 100% Acrylic Finish	131	E	Commercial quality
Frazee Royal Supreme Exterior 100% Acrylic Low Luster Finish	110	E	Top of the line quality, washable, fade resistant, superior adhesion
ICI Dulux Professional Exterior 100% Acrylic Flat Finish	156	E	Premium quality, exceptional mildew resistance, low temperature application to 35oF, good resistance to early moisture exposure, durable and tough, fade and chalk resistant, excellent adhesion, resists blistering, peeling and flaking, easy application
ICI Dulux Exterior Latex Flat Finish	106	E	Highest quality premium, exceptional weathering resistance, easy application, durable and tough, fade and chalk resistant, exceptional mildew resistance, moisture resistant, excellent adhesion, resists blistering, peeling and flaking
ICI Dulux Ultra-Hide Durus Exterior Acrylic Flat Finish	241	E	Professional best, excellent mildew resistance, easy application, fade and chalk resistant, moisture resistant, durable and tough, excellent adhesion, resists blistering, peeling and flaking, excellent touch-up
ICI-Dulux Uitra-Hide Durus Exterior Acrylic Flat Masonry Finish	143	E	Professional best, excellent mildew resistance, easy application, excellent color retention, chalk resistant, durable and tough, resists blistering, mildew, and staining, excellent touch-up, resists erosive effects of coastal salt air
ICI Dulux Speed-Cote Exterior Acrylic Flat Finish	128	E	Fade and chalk resistant, easy application, mildew resistant
Rodda Paint Hi Hide Velvet Flat Latex House Paint	112	E	Premium quality, one coat coverage, mildew resistant, excellent resistance to peeling, fading, blistering, chalking, sun and water fumes
Rodda Paint Ext Alkyd Flat House Paint	362	E	Highly durable, fume resistant, excellent resistance to moisture
Rodda Paint Lasyn Velvet Flat Wall Paint	120	I	Dries within 15 minutes, minimizing dirt pick-up, flows and levels well, excellent color retention and adhasion, will not blister, withstands an alkaline atmosphere
Rodda Paint Master Painter Latex Flat Wall Paint	120	I	Good resistance to moisture
Sherwin Williams Everclean Interior Latex Flat	152-215	I	Provides the washability and durability usually found in glossy enamel finishes. Allows most household stains to be removed without the need for scrubbing
Sherwin Williams Classic 99 Interior Latex Flat Ceiling Paint	158	I	No specific performance information provided
Sherwin Williams Classic 99 Interior Latex Flat	72-180	I	Provides one coat hiding over many colors on smooth surfaces and will provide a durable, scrubbable, washable finish
Sherwin Williams Duration Exterior Latex Flat Coating	89-113	E	Provides the most durable and longest lasting coating available, one coat protection, self-priming, easy application, superior hiding, thicker, more flexible, resists blistering and peeling
Sherwin Williams LowTemp 35 Exterior Latex Flat	101-135	E	Quality product recommended for use down to a surface and air temperature of 35o F
Sherwin Williams SuperPaint Exterior Flat Latex	96-144	E	Finest quality exterior flat finish

¹ I = Interior, E = Exterior, I/E = Interior and Exterior

2. Non-Flat Coatings – Low and Medium Gloss

Product Category Description:

Non-flat coatings are low to high gloss coatings that are widely used on both interior and exterior surfaces of residential and commercial buildings. They are defined as having a gloss of 15 or greater on an 85^o meter and 5 or greater on a 60^o meter. Non-flat coatings are often described using terms such as "eggshell," "satin," "semi-gloss," and "enamel." Non-flat coatings tend to resist stains better than flat coatings and tend to be more washable. The greater shine of non-flat coatings may show surface flaws more than flat coatings.

For the purposes of the 1998 ARB Architectural Coatings Survey, the non-flat category has been divided into three subcategories: low, medium, and high gloss. High gloss coatings, which are defined as having a dried film gloss of 70 or above on a 60^o meter, have been broken into a separate subcategory for which we are proposing a higher VOC limit than that for low and medium gloss coatings. The distinction between the low and medium gloss subcategories is continued here only for the purpose of presenting information. The same VOC limit is proposed for low and medium gloss non-flat coatings.

Tables VI-3a-b below summarize our estimates of sales and VOC emissions from low and medium gloss non-flat coatings category based on the ARB survey results. The 1998 ARB survey shows that the low and medium gloss subcategories have a large California sales volume. Medium gloss coatings, with 18 percent of the sales volume, is the second largest coating subcategory behind flat coatings. Low gloss coatings is the fifth largest subcategory, with 5 percent of the sales volume (ARB, 1999).

With regard to VOC emissions, low and medium gloss non-flat coatings emit over 8 tons per day in California, excluding emissions in the South Coast AQMD. The 1998 ARB survey found that the medium gloss subcategory has the third highest emissions of all the coatings categories, representing 12 percent of the total VOC emissions from architectural coatings. Low gloss coatings represent three percent of architectural coatings emissions. Most of the emissions from low and medium gloss coatings are from water-based products, in spite of the relatively lower VOC content of those products, because the great majority of the products sold are water-based (ARB, 1999).

 

Table VI-3a Non-Flat Coatings – Low Gloss*
	Number of Products	Category Sales (gallons/year)	Sales-Weighted Average VOC (grams/liter)**	VOC Emissions (excluding South Coast AQMD) (tons/day)
Solvent-Based	30	34,373	341	0.07
Water-Based	821	4,440,720	133	1.65
Total	851	4,475,094	134	1.73

* Based on ARB’s 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.

 

Table VI-3b Non-Flat Coatings – Medium Gloss*
	Number of Products	Category Sales (gallons/year)	Sales-Weighted Average VOC (grams/liter)**	VOC Emissions (excluding South Coast AQMD) (tons/day)
Solvent-Based	246	522,186	287	0.94
Water-Based	1,893	15,107,606	151	5.80
Total	2,139	15,629,792	155	6.75

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

Typically, non-flat coatings can be brushed, rolled, or sprayed on the surface to be painted. "Do-it-yourselfers" and paint contractors can purchase non-flat coatings at outlets including hardware stores, home supply stores, and retail paint stores. Non-flat coatings are commonly used on surfaces where frequent cleaning is necessary and in rooms where moisture is present. Kitchens, bathrooms, hallways, and children's rooms are often painted with non-flat coatings. Commercial buildings and institutions commonly use non-flat coatings on surfaces such as walls, corridors, and stairwells. Doors, window frames, shutters, and wood trim are typically painted with non-flat coatings, especially higher gloss coatings. With proper surface preparation and priming (if necessary), non-flat coatings can be used on a large variety of interior and exterior substrates including drywall, plaster, concrete block, wood, and metal. Most low and medium gloss coatings (94 percent for each subcategory) are sold in size units greater than one liter. (ARB, 1999).

The 1998 ARB survey showed that about 44 percent of the low gloss coatings sold in 1996 were formulated for interior applications, 23 percent for exterior applications, and 32 percent were formulated for both interior and exterior applications. For medium gloss coatings, about 48 percent were formulated for interior applications, 12 percent for exterior applications, and 40 percent were formulated for both interior and exterior applications. (ARB, 1999).

For marketing their products, some manufacturers of "zero VOC" non-flat coatings emphasize the health benefits of using such coatings versus conventional coatings. The benefits include the low-to-minimal odor of zero VOC coatings and the reduced chemical exposures from the use of such coatings. Because of those features, manufacturers of zero VOC coatings emphasize the coatings' suitability for use in enclosed centrally-ventilated buildings (e.g. schools, office buildings, and hospitals), rooms that need to be occupied soon after painting (e.g. restaurants, hotel rooms), and residences.

Product Formulation:

As mentioned above, most low gloss coatings are water-based. The 1998 ARB survey (which reflected 1996 sales) shows that water-based low-gloss coatings represent about 99 percent of the market for that subcategory. Solvent-based low gloss coatings represent about one percent of the market. The sales volume of solvent-based low gloss coatings has decreased approximately 60 percent since the 1993 ARB survey of architectural coatings (which reflected 1990 sales), while overall sales of low gloss coatings increased 7 percent over the same period. The overall sales-weighted average VOC content of low gloss coatings decreased 18 percent between 1990 and 1996 (ARB, 1999).

Similarly, most medium gloss coatings are water-based, but the proportion of solvent-based sales is somewhat greater than that of low gloss coatings. The 1998 ARB survey shows that water-based medium gloss coatings represent about 97 percent of the market for that subcategory. Solvent-based medium gloss coatings represent about three percent of the market. The amount of solvent-based medium gloss coatings sold has decreased approximately 65 percent since the 1993 ARB survey, while overall sales of medium gloss coatings has increased 11 percent over the same period. The overall sales-weighted average VOC content of medium gloss coatings decreased 12 percent between 1990 and 1996 (ARB, 1999).

As discussed for flat coatings, the type of binder used in a formulation generally has a large influence on the amount of VOC needed. Binders serve to hold the paint together in a film and to provide adhesion to the substrate. As the gloss level of paint increases, the relative amount of binder as compared to other solid ingredients (i.e. pigment) also tends to increase. The binder in water-based non-flat coatings, which comprise the majority of non-flat coatings, is typically a dispersion of synthetic resin particles, called latex. Thus, these types of coatings are commonly called latex coatings. A wide variety of synthetic polymers are used as binders in latex coatings. Two common latex binders are acrylic and vinyl-acrylic resins. The solvent-based coatings in this category are commonly formulated using alkyd resins as binders. Such solvent-based coatings generally exceed the 250 g/l VOC limit currently in effect in California districts that have architectural coatings rules.

The VOCs in water-based coatings perform one or more of the following functions: binder coalescing aid, polymer plasticizer, freeze/thaw stabilizer, defoamer, and carriers for other additives such as colorants, thickening agents, surfactants, and biocides. The largest contributors of VOCs in latex coatings are glycols, added mainly to provide freeze/thaw resistance, and coalescing solvents such as 2,2,4-trimethyl-1,3-pentanediol isobutyrate (Texanol®), to allow the latex particles to come together to form a film (Klein, 1993). Generally, so called "zero VOC" coatings contain very small amounts of VOCs. Lower-VOC coatings tend to be formulated using binders that require less coalescing solvent and/or are formulated using less VOCs for freeze/thaw stabilization (Klein, 1993; Currie, 1993).

Proposed VOC Limit and Basis for Recommendation:

We are proposing a 150 g/l VOC limit for low and medium gloss non-flat coatings, effective January 1, 2003. The proposed VOC limit is technologically and commercially feasible by January 1, 2003, based on our review of ARB survey data on marketshares, product information from manufacturers, laboratory performance tests, and information on available resin technology as discussed below.

The proposed limit is lower than the national limit recently promulgated by the U.S. EPA for the non-flats category. The U.S. EPA divides non-flat coatings into interior and exterior categories, but the same VOC limit, 380 g/l, applies to both (U.S. EPA, 1998). In California, the 1989 SCM for architectural coatings recommended a 250 g/l VOC limit for non-flat coatings (ARB, 1989); this is the most common limit currently in effect for those California air pollution control districts that have architectural coatings rules. In 1999, the South Coast AQMD adopted a 150 g/l limit for non-flat coatings that will become effective July 1, 2002, and also adopted a 50 g/l limit that will become effective July 1, 2006. Our proposed 150 g/l limit for low and medium gloss coatings is consistent with the interim limit for non-flat coatings adopted by the South Coast AQMD.

As shown in Table VI-4a, the 1998 ARB survey found that about 76 percent of the marketshare of low gloss coatings comply with the proposed VOC limit. About 470 of the 850 products reported comply with the proposed limit. Of the 29 companies that reported for this subcategory, 22 offered low gloss coatings that comply with the proposed limit. A number of low gloss products have a VOC content lower than the proposed limit. Products with a VOC content equal to or lower than 100 g/l represent about 19 percent of the market. Products with a VOC content equal to or lower than 50 g/l represent about 4 percent of the market (ARB, 1999).

As shown in Table VI-4b, the 1998 ARB survey found that about 57 percent of the marketshare of medium gloss coatings comply with the proposed VOC limit. About 810 of the 2,100 products reported comply with the proposed limit. Of the 50 companies that reported for this subcategory, 28 offered medium gloss coatings that comply with the proposed limit. A number of medium gloss products have a lower VOC content than the proposed limit. Products with a VOC content equal to or lower than 100 g/l represent about 23 percent of the market. Products with a VOC content equal to or lower than 50 g/l represent about 2 percent of the market (ARB, 1999).

Tables VI-4a-b also show that VOC emission reductions in the non-South Coast AQMD portion of California would be approximately 0.1 and 1.1 tons per day for low and medium gloss coatings, respectively, (about 1.2 tons per day total) on an annual average basis, from implementing the proposed 150 g/l limit.

 

Table VI-4a - Low Gloss Non-Flat Coatings*
Proposed VOC Limit (g/l)	Number of Complying Products	Complying Marketshare (%) by Volume	Emission Reductions (excluding South Coast AQMD) (tons/day)
150	472	75.7	0.11

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

 

Table VI-4b - Medium Gloss Non-Flat Coatings*
Proposed VOC Limit (g/l)	Number of Complying Products	Complying Marketshare (%) by Volume	Emission Reductions (excluding South Coast AQMD) (tons/day)
150	805	57.3	1.06

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

The following discussion distinguishes between products formulated for interior versus exterior use. The 1998 ARB survey indicates that 62 percent of the volume of interior low gloss coatings sold comply with the proposed limit, 94 percent of exterior low gloss coatings comply, and 83 percent of low gloss coatings sold for both interior and exterior use already comply. Those marketshares represent 167 products, 196 products, and 56 products, respectively
(ARB, 1999).

Similarly, 58 percent of the volume of interior medium gloss coatings sold comply with the proposed limit, 70 percent of the exterior medium gloss coatings comply, and 53 percent of the medium gloss coatings sold for both interior and exterior use already comply. Those marketshares represent 383 products, 268 products, and 112 products, respectively (ARB, 1999).

The high marketshares that comply with the proposed VOC limit demonstrate widespread use of existing low VOC technology for low and medium gloss coatings. Most of the existing non-flat coatings with a VOC level of 250 g/l or less (the most common current limit for those districts that have architectural coatings rules) are water-based latex products, although some solvent-based products are at or below that limit (ARB, 1999). To meet the proposed 150 g/l VOC limit, it is likely that noncomplying water-based products would need to be reformulated using lower VOC technology. As discussed above, the primary sources of VOCs in latex coatings are coalescing solvents and VOCs (glycols) added mainly to provide freeze/thaw resistance. We expect that product reformulation of water-based latex products to meet the proposed limit would involve switching to a binder (or blend of binders) that requires less coalescing solvent and/or reducing the amount of glycol that is added to provide freeze/thaw stability (Klein, 1993, Currie, 1993). It is also likely that most solvent-based coatings would need to be reformulated to be water-based or to use low-VOC alkyd core-shell technology (e.g., Vianova Resins, 1999).

Laboratory performance tests

National Technical Systems. Independent laboratory performance tests of a number of coatings were recently conducted by National Technical Systems (NTS) under contract with the South Coast AQMD. Included in those tests were 14 interior and 13 exterior non-flat coatings. Of those coatings, 9 had a VOC content below 150 g/l (range: 0 to 135 g/l), 10 had a VOC content at or below 250 g/l (range: 170 to 250 g/l) and the remaining 8 had VOC levels that ranged from 400 to 420 g/l. The coatings with VOC levels of 400 g/l or greater were mostly "quick-dry enamels," and the test results for those coatings are discussed in the quick-dry enamel category description. For this discussion, those coatings that comply with the proposed 150 g/l limit ("lower VOC coatings") are compared with those coatings with a VOC content above 150 g/l that comply with the most common current limit of 250 g/l ("higher VOC coatings"). Similar performance was seen in tests of brushing properties, sag resistance, and hiding. Dry-to-touch times were also similar, but dry hard times tended to be somewhat shorter for lower VOC coatings. The lower VOC coatings tended to have slightly less leveling performance than the higher VOC coatings, but this difference was mostly seen with the 0 VOC coatings. Dry film thickness tended to be slightly higher in the lower VOC coatings. Resistance to blocking was similar for the interior coatings, while resistance to blocking for the exterior coatings tended to be better in the lower VOC product group. Interior coatings were also tested for dirt removal ability and scrub abrasion resistance, where the higher VOC coatings tended to perform somewhat better (NTS, 1999).

NTS also tested primer/topcoat systems with non-flat coatings as topcoats. Included in those tests were 14 interior and 12 exterior systems with non-flat topcoats. Of those topcoats, 11 had a VOC content below 150 g/l (range: 0 to 135 g/l), 9 had a VOC content at or below 250 g/l (range: 220 to 250 g/l) and the remaining 6 had a VOC level of 400 g/l. ARB staff compared the results for those topcoats that comply with the proposed 150 g/l VOC limit with those topcoats with VOC levels greater than 150 g/l but less than or equal to 250 g/l. Our comparison indicates that lower and higher VOC interior systems had comparable performance with regard to adhesion tests and resistance to household chemicals. However, the lower VOC topcoat systems tended to show slightly more softening in response to chemical exposure. The exterior systems showed similar performance with regard to dry film thickness and water resistance (NTS, 1999).

Harlan Associates. In 1995, Harlan Associates, Inc., under contract with ARB, conducted performance tests on 10 interior and 10 exterior non-flat coatings. Those coatings were selected in 1994 from commercially available coatings. The VOC levels of the twenty coatings ranged from 15 g/l to 459 g/l. Thirteen were high gloss coatings, six were medium gloss, and one was low gloss. Four of those coatings, 3 interior (medium gloss) and 1 exterior (low gloss), had VOC levels below 150 g/l. The low VOC non-flat coatings were similar to higher VOC coatings with regard to stability, hardness, application, and appearance. Results of tests for adhesion showed that two low VOC coatings had good to excellent adhesion, while two had poor to mediocre adhesion. In comparison, many of the higher VOC coatings had good to excellent adhesion, while two of those coatings rated "poor" to "fail" on the adhesion test. One low-VOC coating failed the block resistance test (the resistance of two painted surfaces to stick to each other), two rated "good" to "very good", and one rated "excellent." In comparison, the higher VOC coatings rated "fail" to "excellent" in block resistance. One low VOC coating failed the flexibility test, while all the other coatings passed. Two low VOC coatings (only interior coatings tested) passed the scrub resistance test, while one wore through at 400 cycles. In comparison, five of the higher VOC coatings passed the scrub resistance test, while two wore through sooner than 400 cycles (ARB, 1995; Cowen, 1999).

Consumers Union. Consumers Union, an independent, nonprofit organization, recently reported on tests it performed on interior and exterior paints. Tests were performed on 15 brands of interior low-luster paints marketed as higher-grade paints. For each brand, three colors that represent the basic tint bases were tested. A number of satin and eggshell paints with VOC levels below 150 g/l were included in the tests, including four "zero VOC" paints. The paints were tested for hiding ability and resistance to scrubbing, staining, blocking, fading, and mildew. All the paints tested performed well, rating "good" or better in overall scores. Sears Best Easy Living Satin, which complies with the proposed VOC limit, was recommended as one of the four best low-luster paints and received the highest overall score. The second-highest rated paint, House Beautiful Satin, with a VOC content that ranges from 117 to 156 g/l depending on the tint base, comes close to complying with the proposed limit (Consumer Reports, 2000).

Consumers Union also tested 17 brands of exterior latex non-flat paints (three colors for each brand) purchased mostly from the northeastern United States. A number of paints tested comply with the proposed 150 g/l limit. The paints were applied to Southern yellow pine, a type of wood prone to cracking, and were exposed to the weather in New York and Florida for nearly two years. Periodic assessments were made for signs of cracking, color change, dirt buildup, mildew growth, and other problems. The investigators also tested how well the paints adhered to a chalky surface. Based on the test results, four low-luster and four semi-gloss paints received a recommendation from Consumers Union. Three of the four recommended low-luster paints comply with the proposed limit. Those three paints are Glidden Dulux Endurance Satin, Sears Best Weatherbeater Satin, and Sears Weatherbeater Satin. One of the four recommended semi-gloss paints, Sears Best Weatherbeater Semi-Gloss, complies with the proposed VOC limit (Consumer Reports, 1999).

Product information from manufacturers

Product information sheets published by coatings manufacturers indicate that a variety of low to medium gloss coatings that meet the proposed VOC limit are available that possess performance characteristics similar to higher VOC coatings. At the end of the discussion of this category are tables of information about specific products that meet the proposed VOC limit and, for comparison, products that exceed the proposed limit. We were able to identify specific products with a VOC content of 150 g/l or less from AFM, Con-Lux, Dunn Edwards, Evr-Gard, Flex Bon, Griggs Paint, ICI Dulux, Kelly-Moore, Sherwin Williams, and Spectra-Tone.

A list of performance characteristics compiled from product information sheets for low and medium gloss non-flat coatings (often described as satin, eggshell, or semi-gloss finishes) with VOC levels of 150 g/l or less is presented below. The compilation distinguishes between interior and exterior products; characteristics of coatings formulated for dual interior/exterior use are included under both categories. Please note that not all low and medium gloss coatings with VOC levels at or below 150 g/l possess all of the characteristics listed below.

Low and medium gloss interior coatings

Low and medium gloss exterior coatings

professional best, premium quality, highest quality premium good to excellent adhesion excellent moisture resistance excellent one coat coverage very good block resistance easy application, high speed application durable, highly durable finish, extremely abrasion resistant excellent color retention stain resistant excellent washability bonds to glossy surfaces very good touch-up properties good dry hide, excellent hide mildew resistant resists yellowing high build

professional best, best quality, premium quality, highest quality premium the most durable and longest lasting coating available, superior durability, durable and tough, outstanding exterior durability extremely abrasion resistant extremely washable superior color retention, excellent color and gloss retention superior to exceptional mildew resistance flexible exceptionally smooth finish superior hiding shields the surface from the elements that cause film failure (grain crack, peeling, blistering), resists blistering, peeling and flaking exceptional weathering resistance fade and chalk resistant moisture resistant excellent adhesion easy application long lasting uniform finish recommended for use down to a surface and air temperature of 35o F one coat protection self-priming

Available resin technology

The South Coast AQMD recently surveyed current and emerging technology available for formulating non-flat coatings. ARB staff concurs with the findings of the South Coast AQMD based on our own discussions with resin manufacturers. The South Coast AQMD identified a number of resin manufacturers that have developed technologies for use in developing non-flat coatings that comply with the proposed 150 g/l limit. Technologies identified by the South Coast AQMD include those offered by Rohm and Haas, BASF, Conlux, Air Products and Chemicals, and Vianova Resins (South Coast AQMD, 1999; BASF, 1999; Vianova Resins, 1999).

Issues:

1. Issue: The non-flat coatings category covers a broad range of products. The ARB should consider subcategorizing the non-flat coatings category to allow for a higher VOC limit for special use, high performance products. Two specific suggestions are to split the non-flat coatings category into interior and exterior subcategories, and to further split these subcategories into a high-gloss subcategory and another subcategory for the remaining non-flat coatings. A VOC limit of 250 g/l was suggested for the high gloss subcategory.
Response: Our survey of product information published by paint manufacturers indicates that a wide variety of interior and exterior low and medium gloss coatings comply with the proposed limit. This includes coatings formulated for contractors (which emphasize features such as ease and speed of application, hiding properties, and touch-up properties), high-build coatings, coatings designed for low temperature application, and premium quality coatings.

We distinguished between interior and exterior coatings in our evaluation, and also distinguished between low, medium, and high gloss coatings. As discussed above, information on marketshares obtained from the ARB survey indicates that a considerable portion of existing interior and exterior low and medium gloss coatings already comply with the proposed 150 g/l limit. Our survey of product information sheets for complying low and medium gloss coatings shows that a variety of performance characteristics comparable to those of higher VOC products have been achieved for both interior and exterior coatings. Thus, available information does not support subdividing low and medium gloss coatings into interior and exterior subcategories.

As discussed in the high gloss non-flat coatings subcategory, we have modified the proposed SCM to include a separate subcategory with a VOC limit of 250 g/l for high gloss coatings, primarily due to enforcement concerns because of the overlap between non-flat high gloss and quick-dry enamels.


2. Issue: The 150 g/l limit for non-flat coatings will adversely affect a number of performance characteristics of those coatings. Characteristics that will be compromised include film durability, scrub resistance, stain removal properties, low temperature application properties, freeze-thaw resistance, and block resistance. Also, the coatings with the best performance characteristics (durability and resistance to the following: deterioration by water; corrosion, physical contact; loss of adhesion; erosion; film cracking; discoloration; household chemical attack; and the effects of sunlight) require "hard" resins that must be formulated with VOC levels above 200 g/l to achieve maximum performance. The NTS study shows that flow and leveling characteristics are superior for alkyd paints (>350 g/l VOC) when compared to the water based products (150-250 g/l VOC) and the 150 g/l paints tested did not show the highest performance levels achievable.

Response: A subcategory for high gloss non-flat coatings has been created with a 250 g/l VOC limit, primarily due to enforcement concerns. (See the high gloss non-flat coatings subcategory for more detailed information.) We disagree with the comment that high quality low and medium gloss coatings cannot be formulated at 150 g/l with current technology. Our conclusion is based on laboratory performance tests viewed in conjunction with information published by coatings manufacturers.

Specifically, the laboratory tests conducted by NTS show comparable performance for lower VOC non-flat coatings when compared to higher VOC non-flat coatings in many performance areas listed in the above comment. For the purposes of staff's evaluation of non-flat coatings, it was appropriate to compare coatings that comply with the proposed 150 g/l limit with higher VOC coatings that comply with the most common current California district limit of 250 g/l. The high VOC coatings (> 350 g/l) mentioned in the above comment would not be allowed under current district rules for non-flat coatings, and were thus excluded from that comparison. Moreover, most of those high VOC coatings (> 350 g/l) tested were "quick-dry enamels." Such coatings must meet specific gloss and dry time criteria, and are classified in a separate category from non-flat coatings. It only appropriate to use the NTS results for those coatings in the context of evaluating the proposed VOC limit for the quick-dry enamel category, as was done by ARB staff.

Our survey of product information sheets indicates that there are a number of complying interior and exterior low and medium gloss coatings that are identified by their manufacturers as premium quality coatings. Further, the product information indicates that there are complying coatings that are described as having superior durability and that have excellent performance in the other areas listed in the above comment. Also, there are complying products that allow for low temperature application and products with very good block resistance. Available information also suggests that the 150 g/l limit allows for the formulation of non-flat coatings with sufficient freeze-thaw resistance. Thus, our survey of product information indicates that a variety of manufacturers have been able to use available technology to achieve a balance in desirable properties for low and medium gloss coatings with VOC levels at or below 150 g/l.


3. Issue: The qualities claimed by manufacturers for their products are marketing terms that de-emphasize compromises made necessary by excessively stringent VOC content limits and do not indicate a guarantee of the ultimate of performance.

Response: We believe it is appropriate to use product data sheets published by coating manufacturers in conjunction with test results and other information in our assessment of non-flat coatings. Coating manufacturers publish the product data sheets to provide customers with information regarding important characteristics of their coatings. The information contained in the product data sheets is typically based on laboratory tests and may also be based on field studies. The above comment states that the product information sheets are simply marketing tools and do not guarantee performance. We believe that customers rely on the information contained in the sheets to assist them in choosing products, and that providing inaccurate information as a marketing tool does not make good business sense as it would alienate customers. Also, more credence is given to the information contained in product data sheets when similar performance claims are made for complying and non-complying products, and when different manufacturers make similar performance claims for complying products.


4. Issue: Low VOC interior paints may cause an indoor air quality problem, especially with the elimination of mercury as an additive. Glycols act as preservatives, and if you reduce the glycol concentrations in paints, you might see increased health hazards due to microbial growth inside buildings.

Response: Microbial growth on paint after it is applied to the substrate is primarily caused by moisture in the environment and to a lesser degree by warm temperatures. Thus, mildew growth on paint is fairly common in tropical climates. There are numerous non-mercury additives in common use in the coatings industry, including the pigment zinc oxide, that suppress the growth of mildew. Moreover, glycols evaporate after the paint is applied to the substrate and would thus not be retained in the paint over the long term. Further, the South Coast AQMD reports that independent testing by NTS shows no difference in mildew resistance in the high VOC vs. the low-to-zero-VOC non-flat coatings tested (Berry, 2000).

Product Category Description:

Non-flat coatings are described in the previous section on low and medium gloss non-flat coatings. For the purposes of the 1998 ARB Architectural Coatings Survey, the non-flat category has been divided into three subcategories: low, medium, and high gloss. High gloss coatings, which are defined as having a dried film gloss of 70 or above on a 60o meter, have been broken into a separate subcategory for which we are proposing a higher VOC limit than that for low and medium gloss coatings. Many high gloss coatings meet the gloss and dry-time criteria of quick-dry enamel coatings, a separate category in the proposed SCM with the same proposed VOC limit as the high gloss non-flat subcategory. Please see the quick-dry enamel category description for more detailed information on that coating classification.

Table VI-5 below summarizes our estimates of sales and VOC emissions from high gloss non-flat coatings based on the ARB survey results. The 1998 ARB survey shows that the high gloss non-flat subcategory, with two percent of the California sales volume, is the ninth largest subcategory with regard to sales. With regard to VOC emissions, high gloss non-flat coatings emit approximately two tons per day in California, excluding emissions in the South Coast AQMD. The 1998 ARB survey found that the high gloss non-flat subcategory contributes 4 percent of the architectural coatings emissions and is the eighth highest subcategory. In contrast to low and medium gloss non-flat coatings, where emissions are due predominantly to water-based products, emissions from high gloss coatings are more evenly split among solvent-based and water-based products, with emissions from solvent-based products somewhat greater than those from water-based products (ARB, 1999).

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

The previous section on low and medium gloss non-flat coatings describes how non-flat coatings are used and marketed. High gloss coatings are frequently used on surfaces such as doors, window frames, shutters, and wood trim. The 1998 ARB survey showed that most high gloss coatings (88 percent) are sold in size units greater than one liter. The survey also showed that about 36 percent of the high gloss coatings sold in 1996 were formulated for interior applications, 15 percent for exterior applications, and 48 percent were formulated for both interior and exterior applications (ARB, 1999).

Product Formulation:

The formulation of non-flat coatings is described in the previous section on low and medium gloss non-flat coatings. Most high gloss coatings are water-based. Water-based products represent about 75 percent of the market and solvent-based products represent about 25 percent of the market for this subcategory. The amount of solvent-based high gloss coatings sold has decreased approximately 64 percent since the 1993 ARB survey of architectural coatings, while overall sales of high gloss coatings has increased 46 percent over the same period. The overall sales-weighted average VOC content of high gloss coatings decreased 17 percent between 1990 and 1996 (ARB, 1999).

Proposed VOC Limit and Basis for Recommendation:

We recommend a 250 g/l VOC limit for the high gloss non-flat coating subcategory, effective January 1, 2003. In California, the 1989 SCM for architectural coatings recommended a 250 g/l VOC limit for non-flat coatings (ARB, 1989); this is the most common limit currently in effect for those California air pollution control districts that have architectural coatings rules. Thus, the proposed 250 g/l limit for the high gloss subcategory would retain the limit currently in effect for such coatings in those districts.

The proposed limit is lower than the national limit recently promulgated by the U.S. EPA for the non-flat coatings category. The U.S. EPA divides non-flat coatings into interior and exterior categories, but the same VOC limit, 380 g/l, applies to both (U.S. EPA, 1998). In 1999, the South Coast AQMD adopted a 150 g/l limit for non-flat coatings that will become effective July 1, 2002, and also adopted a 50 g/l limit that will become effective July 1, 2006. The South Coast AQMD also adopted a 250 g/l limit for a related category, quick-dry enamels, that will become effective July 1, 2002, and a 50 g/l limit for that category that will become effective July 1, 2006. Our proposed 250 g/l limit for high gloss coatings is consistent with the interim limit adopted by the South Coast AQMD for quick-dry enamel coatings.

Our recommendation for a 250 g/l VOC limit for high gloss coatings is due primarily to enforcement concerns, especially for California districts with fewer enforcement resources than the South Coast AQMD. Many high gloss non-flat coatings satisfy the gloss and dry time criteria of quick-dry enamels, a separate category in the SCM with a proposed VOC limit of 250 g/l. We recognize that there is overlap between the high gloss non-flat and the quick-dry enamel categories, and that companies could relabel products rather than reformulate them if the VOC limit is different for those two categories. Moreover, some high gloss products might be illegally labeled as quick-dry enamels even if they do not meet the dry time criteria, which would be problematic for enforcement personnel in some districts to detect. For greater enforceability, the proposed SCM includes a subcategory for high gloss non-flat coatings that has the same VOC limit as the quick-dry enamel category. Since most districts' architectural coatings rules currently include a quick-dry enamel category, the proposed SCM retains that category with its new VOC limit. This was done so that district rules, once amended in accordance with the proposed SCM, will clearly show that the VOC limit for quick-dry enamels is reduced from 400 g/l to 250 g/l. Further, we recommend that districts eventually eliminate the quick-dry enamel category from their architectural coatings rules, which would in effect require such products to meet the VOC limit of the high gloss non-flat subcategory.

As shown in Table VI-6A, the 1998 ARB survey found that about 80 percent of the marketshare of high gloss coatings comply with the proposed 250 g/l VOC limit. About 330 of the 800 products reported comply with the proposed limit. About a third (29 percent) of the sales of non-complying products are for liter or smaller size units, which are exempt from district VOC limits (but counted in the marketshare determination). Of the 34 companies that reported for this subcategory, 27 offered high gloss coatings that comply with the proposed 250 g/l limit (ARB, 1999). As mentioned above, the proposed 250 g/l limit for the high gloss subcategory retains the limit currently in effect for such coatings in those districts that have architectural coatings rules. Therefore, no emission reductions are predicted from implementing the proposed VOC limit for this subcategory.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

The 1998 ARB survey indicates that 97 percent of the volume of interior high gloss coatings sold comply with the proposed limit, 46 percent of the exterior high gloss coatings comply, and 79 percent of the high gloss coatings sold for both interior and exterior use already comply. Those marketshares represent 100 products, 82 products, and 136 products, respectively (ARB, 1999).

Laboratory performance tests

Independent laboratory performance tests of a number of coatings were recently conducted by National Technical Systems (NTS) under contract with the South Coast AQMD. Also, in 1995, Harlan Associates, Inc., under contract with ARB, conducted performance tests on 10 interior and 10 exterior non-flat coatings. A comparison of the results of the NTS and the Harlan Associates tests of high gloss coatings with VOC levels at or below 250 g/l as versus those of quick-dry enamel coatings with VOC levels near 400 g/l is included in the quick-dry enamel category discussion.

Product information from manufacturers

Since we are not recommending a change in the current VOC limit for high gloss coatings, we have not included a discussion of product information published by coatings manufacturers for such products here. However, for completeness, we identified four high gloss products with VOC levels of less than 150 g/l, and included their performance characteristics in the table that follows the discussion of the low and medium gloss non-flat coatings category. Those products were from Con-Lux, Griggs Paint, Pittsburgh Paints, and Sherwin Williams. Also, please see the quick-dry enamel category discussion for a review of the performance characteristics published by product manufacturers of high gloss, quick-drying coatings that meet the 250 g/l limit.

Issues:
1. Issue: The Draft Environmental Impact Report indicates that high gloss paints that comply with the proposed 150 g/l VOC limit for non-flat coatings comprise only 46 products with 2.6 percent of the marketshare. The low marketshare suggests that those products don't work and people aren't buying them as a consequence. Also, ARB appears to use the logic that a high marketshare of complying products indicates that the proposed VOC limit is feasible for a given category. If that is the case, then the converse should be true - a low complying marketshare should indicate that the proposed VOC limit does not adequately allow formulation of paints that fill the needs of the category. High gloss paints have a complying marketshare of only 2.6 percent, indicating the proposed VOC limit is not feasible.

Response: The marketshare of complying products is just one element we considered in our evaluation of the feasibility of the proposed VOC limit. We also evaluated product information from manufacturers, laboratory performance tests, and information on available resin technology. However, as discussed above, after further evaluation we are now recommending that the non-flat coatings category include a separate subcategory for high gloss coatings with a VOC limit of 250 g/l, primarily due to enforcement concerns. The complying marketshare for high gloss products at the proposed 250 g/l limit is approximately 80 percent.

2. Issue: The proposed 150 g/l VOC limit for non-flat coatings will not allow for the formulation of quality high-gloss exterior coatings. There are no suitable resins available that allow for the formulation of premium quality high gloss exterior coatings. ARB staff should be truthful to the Board and explain that a 150 g/l VOC limit for high gloss paints will result in some sacrifices in performance. The market dictates this to a degree, but the proposed 150 g/l VOC limit amounts to the government dictating a decrement in performance. It is not right to pretend that performance won't be affected by the limit.

Response: We identified several high gloss exterior (including interior/exterior) coatings on the market with VOC levels less than 150 g/l that are classified as premium quality by their manufacturers. However, as discussed above, we have modified the proposed SCM to include separate subcategory for high gloss coatings with a VOC limit of 250 g/l, primarily due to enforcement concerns.

4. Antenna Coatings

Product Category Description:

Antenna coatings are primers or topcoats designed for application to equipment and associated structural appurtenances that are used to receive or transmit electromagnetic signals. For example, these coatings are used on the satellite dishes and supporting structures used by the National Radio Astronomical Observatory (NRAO) and the National Aeronautics and Space Administration (NASA). The coatings are designed to minimize signal losses while protecting the antenna's metal surfaces from corrosion. These products should produce thin films, to avoid losses in signal strength, and should also scatter infrared waves, to avoid generating excess heat at the antenna's receiver (Triangle Coatings, 10/18/99).

We are proposing to add a new category for antenna coatings in the SCM. These coatings are not regulated in district architectural coatings rules as a separate category (but instead are subject to the industrial maintenance category). However, as explained below, we believe that a new category and VOC limit for these products is justified. In addition, the U.S. EPA's national architectural coatings rule contains a separate category and VOC limit for these products.

No antenna coatings were reported in the ARB's 1998 Architectural Coatings Survey. However, one manufacturer subsequently provided sales volumes in California, and VOC content information, indicating that these products contribute VOC emissions less than 0.01 tons per day statewide, excluding the South Coast AQMD.

Product Use and Marketing:

Antenna coatings are highly specialized paints used exclusively to paint satellite dishes and related equipment, and are not available to the general public. As mentioned above, the dry film thickness should be as thin as possible while still providing corrosion protection. As such, it may be necessary to completely remove all old coatings during repainting operations. Some antenna operators have developed detailed procedures that painting contractors must follow regarding surface preparation and painting application techniques (JPL, 2/15/96).

Product Formulation:

We are only aware of one manufacturer of antenna coatings. This manufacturer currently produces:

1. a solvent-based zinc chromate primer and a solvent-based flat white topcoat (Triangle No. 6), for reflective surfaces; and
2. a solvent-based glossy white topcoat (Triangle No. 710) for nonreflective surfaces, such as the antenna's supporting structures. This manufacturer has also developed a solvent-based acrylic-urethane replacement for the primer/topcoat system for reflective surfaces that does not require a primer. This system reportedly has superior performance with respect to the minimization of signal losses compared to the existing system (Otoshi, 11/15/99). Due to confidentiality concerns, we cannot reveal further details about these formulations.

Proposed VOC Limit and Basis for Recommendation:

We are proposing a 530 g/l VOC limit for antenna coatings, effective January 1, 2003. This VOC limit is consistent with the U.S. EPA's national architectural coatings rule. This limit is clearly technologically and commercially feasible because the proposed limit would essentially cap the VOC content of existing products, and would not require reformulation of existing products or result in emission reductions. We believe this proposed VOC level is appropriate because we are not aware of any lower VOC products, or existing technology that would allow for compliance with a lower VOC limit. In addition, lower VOC prototype water-based formulations that have been tested by the Jet Propulsion Laboratory have resulted in greater signal losses compared to existing solvent-based formulations (Otoshi, 8/15/99; Otoshi, 11/15/99; JPL, 12/7/99). The existing products have been extensively tested by the Jet Propulsion Laboratory, and are used by NASA and the NRAO in other antenna installations outside of California. Finally, as mentioned above, the emissions from these products are less than 0.01 tons per day statewide, excluding the South Coast AQMD.

5. Antifouling Coatings

Product Category Description:

Antifouling coatings are products designed for application to submerged stationary structures and their appurtenances to prevent or reduce the attachment of marine or freshwater biological organisms. We are proposing to add a new category for these coating products in the SCM. As defined in the U.S. EPA's national architectural coatings rule, these coatings may or may not be registered with the U.S. EPA as a pesticide. However, we are proposing that they be registered as a pesticide to qualify as an antifouling coating in this proposed SCM, consistent with district marine coatings regulations in California. Antifouling coatings are typically used on underwater structures such as docks, sea walls, oil drilling platforms, piers, and boat slips.

As shown in Table VI-6B below, the antifouling coatings that were reported in the ARB's Architectural Coatings Survey are solvent-based coatings with a sales-weighted average VOC content of 351 g/l. These coatings resulted in less than 0.01 tons per day of VOC emissions statewide in 1996, excluding the South Coast AQMD. Information on sales volumes cannot be provided for this category because not enough products were reported to protect data confidentiality.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.
PD = Protected data.

Product Use and Marketing:

Antifouling coatings, as defined in this proposed SCM, are highly specialized coatings that are also registered pesticides. According to one manufacturer, these products are not generally produced exclusively for submerged architectural structures (Hempel, 12/22/99). Instead, these products are designed primarily for marine vessels, but may also be used on architectural structures. These products are often used by shipbuilders, original equipment manufacturers, and large construction firms (in architectural coatings applications).

Product Formulation:

Due to the limited number of respondents to the ARB's Architectural Coatings Survey, we cannot reveal detailed information about the formulations of antifouling coatings. Based on the ARB survey data, these are solvent-based formulations. Antifoulant coatings in general release cuprous oxide or tributyl tin as the active ingredient that prevents the attachment of biological organisms.

Proposed VOC Limit and Basis for Recommendation:

We are proposing a 400 g/l VOC limit for antifouling coatings, effective January 1, 2003. This VOC limit is slightly lower than the 450 g/l VOC limit in the U.S. EPA's national architectural coatings rule. However, this limit is clearly technologically and commercially feasible because it effectively places a cap on the VOC content of existing products sold in California, as reported in the ARB's Architectural Coatings Survey. The proposed limit would not require reformulation of existing products or achieve emission reductions. We believe the proposed 400 g/l VOC limit is appropriate because it is consistent with the VOC limits for antifouling coatings in California's district marine coatings rules, with the exception of the San Diego Air Pollution Control district's 330 gram/liter VOC limit for pleasure craft (South Coast AQMD; SDAPCD; and BAAQMD). The antifouling coatings used for architectural coatings applications are generally the same as those subject to marine coatings rules. We also note that there were no products reported in the ARB's Architectural Coatings Survey that would meet the 250 g/l VOC limit for industrial maintenance coatings, which is generally the category these products would otherwise fall under. Finally, as mentioned above, the emissions from these products are less than 0.01 tons per day statewide, excluding the South Coast AQMD.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
PD = Protected data.

6. Bituminous Roof Coatings

Product Category Description:

Bituminous roof coatings are products labeled as and formulated exclusively for roofing, that incorporate bitumens. Bitumens are black or brown materials including, but not limited to, asphalt, tar, pitch, or asphaltite that are soluble in carbon disulfide, consist mainly of hydrocarbons, and are obtained from natural deposits or as residues from the distillation of crude petroleum or coal.

Table VI-8 below summarizes our estimate of sales and VOC emissions from the bituminous coatings category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

When we conducted the 1998 ARB survey, we included U.S. EPA's category of bituminous coatings. The data shown above therefore represent pavement sealers, bituminous primers, bituminous roof coatings and some industrial maintenance coatings. After further analysis of survey responses and discussions with several roof-coating manufacturers, we learned that many of the coatings with VOC contents less than 50 g/l are pavement sealers. For the purposes of this proposed SCM, we are limiting this category to bituminous coatings that are applied only to roofs. Those products, which are bituminous roof primers, are regulated under a separate bituminous roof primer category. Bituminous roof coating products that are self-priming are regulated as bituminous roof coatings. In addition, some bituminous roof coatings were reported as roof coatings.

Based on our survey data, discussions with manufacturers, and data supplied by the RCMA, it is staff's estimate that bituminous roof coatings account for approximately 20 percent of the sales volume and 72 percent of the emissions from the bituminous coatings category. In addition, the bituminous roof coating sales and emissions represent 81 and 26 percent, respectively, in the roof coating category. Combining this information with the data supplied by the Roof Coating Manufacturers Association, we estimate that the bituminous roof coating sales are approximately 4.5 million gallons per year statewide and emissions are about 1.1 tons per day excluding the South Coast AQMD. (ARB 1999)

Product Use and Marketing:

Bituminous roof coatings are applied at ambient temperatures (cold-applied) and, when the carrier evaporates, produce a cured water-resistant film. These products are marketed as economical products that are easy to use, and non-flammable. Bituminous roof coatings can be found in major home centers, paint stores and most local hardware stores. (RCMA, undated) They are applied over the main waterproofing membrane to protect against ultraviolet (UV) exposure. These coatings act as a sacrificial maintenance layer that protects and prolongs the life of the main waterproofing layer from UV and climate exposure.

Product Formulation:

Traditional bituminous roof coatings are gelled coatings made from cutback bitumens, petroleum solvents, clay fillers, surfactants, fibers, other fillers and optional reflective pigments. Cutback bitumens are made through a process of refining the distillate bitumens through vacuum distillation or oxidation to produce various physical properties (e.g. dry time, viscosity, etc). They are then dissolved in a petroleum solvent. (RCMA, undated)

Bitumens may also be emulsified in water. Emulsification allows the bitumens to be uniformly suspended in the water. As with the petroleum-based products, the film is formed when the carrier (water) evaporates from the coating and forms a hard dry coating. In addition, there are roof coatings that use a combination of an acrylic or elastomeric (non-bituminous) roof coating and asphalt or coal tar (bituminous) roof coatings. (RCMA, undated)

Proposed VOC Limit and Basis for Recommendation:

The proposed VOC limit of 300 g/l is technologically and commercially feasible by the January 1, 2003, effective date based on the current VOC limit in most districts (300 g/l), and data provided by the Roof Coatings Manufacturers Association (RCMA) which shows extremely high complying marketshare. Those manufacturers that need to reformulate can reduce the amount of petroleum and mix types of asphalt to comply with the proposed limit.

The high complying marketshare with the proposed VOC limit reflects the fact that the survey data are predominated by very low VOC water-based products (asphalt emulsions). However, after a detailed review of the survey data we also noted several solvent-borne bituminous roof coatings with substantial sales that meet the proposed 300g/l limit. Subsequent to the ARB survey, the RCMA supplied us with supplemental data gathered from a survey they conducted. These data showed that all of the water-based products can comply with our proposed limit and that 99 percent of the solvent-based products either meet or are within 50 g/l of the proposed limit. This 300 g/l VOC limit is also consistent with most districts including the current South Coast AQMD limit for bituminous roof coatings. The South Coast AQMD has a future effective limit of 250 g/l for bituminous roof coatings, which is effective in 2002. Due to climatic conditions present outside of the South Coast Air Basin we believe that a slightly higher VOC limit is appropriate for the remainder of the state.

The proposed VOC limit would not apply to all types of bituminous products. For example, bituminous pavement sealers are subject to the proposed VOC limits for flats/nonflats, and those bituminous coatings that are used in industrial maintenance applications and meet the industrial maintenance definition are subject to the proposed limit for the industrial maintenance coatings category. Bituminous roofing primers are subject to the bituminous roofing primer category limit of 350 g/l. Bituminous aluminum roof coatings would be considered metallic pigmented coatings, assuming such coatings meet the metallic pigmented coating definition.

As proposed, the bituminous roof coating category would include a provision for annual reporting, which would require manufacturers to submit their annual sales sold within California. Table VI-9 represents our estimates of the emission reductions from the proposed VOC limit.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

Issues:

1. Issue: The 250 g/l limit for bituminous coatings is technically infeasible.

Response: We believe the previously proposed 250 g/l limit is technically feasible based upon a detailed analysis of our survey data, and the data submitted by industry, in districts with climates similar to the South Coast AQMD. Ninety-eight percent of the bituminous coating market currently complies with the previously proposed 250 g/l limit. However, in order for the SCM to be applicable statewide, and to accommodate climatic conditions which occur more frequently outside the South Coast Air Basin, we believe that it is more appropriate for a 300 g/l limit for areas outside of the South Coast Air Basin. Bituminous roof primers are subject to the bituminous roof primer category.

2. Issue: The data collected in the 1998 Architectural Coatings Survey are incomplete and represent a fraction of the products manufactured and shipped into California.

Response: As discussed above, we have worked with the roof coatings industry to supplement the survey data for this category.

3. Issue: The performance characteristics of solvent-based roof and flashing cements and adhesives are inherently different from water-based bituminous coatings (emulsions). These two distinct types of products are not necessarily substitutes for one another.

Response: Our survey data show that there are solvent-based bituminous roof and solvent-based bituminous flashing cement products that meet the previously proposed 250 g/l limit. Ninety-eight percent of the market meets the proposed 300 g/l limit. Most roof adhesives and those flashing cements meeting the adhesive definitions would not be subject to the proposed VOC limit, since the districts regulate roof adhesives in their adhesive rules. Please check district rules for definitions of these products to determine if the adhesive or architectural coating rule applies.

4. Issue: If patching materials are included in the proposal, we recommend a 400 g/l VOC limit for wet and dry patching material, and a 50 g/l limit for all other patching material. Emulsion-based patching materials cannot be applied in wet conditions to immediately stop a leak, where the solvent-based and dry material can.

Response: Most patching materials are regulated in the adhesive and sealant rules by the local air districts. See local district rules for current limits.

5. Issue: Industry needs the solvent-based mastics at the 250-300 g/l limit in the South Coast AQMD's Rule 1113.

Response: We are now recommending a 300 g/l VOC limit in the SCM.

6. Issue: There is a problem with the definitions of roof and bituminous coatings. They were not adequately distinguished as they were in the National Rule. We would like to see no lower limits for these categories than those limits in the South Coast AQMD.

Response: The ARB staff met with roof and bituminous coating manufacturers to clarify these definitions. We also worked with the RCMA to gather additional data. As discussed above, we believe the South Coast AQMD's 250 g/l limit is feasible in the South Coast Air Basin and those areas with similar climates. However, for a statewide limit, we are recommending a higher 300 g/l limit.

7. Issue: We provided data on the performance of two coatings: a 250 g/l bituminous coating, and a 300 g/l bituminous coating. There are differences in the viscosity of these coatings, especially at lower temperatures.

Response: Please see response to Issue 1.

8. Issue: The proposed 250 g/l limit is precisely half of the limit permitted in the national rule (500 g/l for bituminous coatings). The proposed SCM should include a category for bituminous roof primers with a VOC content limit of 500 g/l.

Response: Please see response to Issue 1 and the Bituminous Roof Primer discussion.

9. Issue: The 250 g/l VOC level for bituminous coatings, as currently proposed, is too low for these products. We request that bituminous coatings be regulated at 300 g/l at a minimum. We request a category for bituminous primers. If regulated under the primers, sealers, and undercoaters category, a 200 g/l VOC limit would ban these products.

Response: Please see response to Issue 1 and the Bituminous Roof Primer discussion.

10. Issue: We are requesting the VOC level for bituminous coatings be no less than 300 g/l in California. We request a breakout category for bituminous primers of at least 400-450 g/l.

Response: Please see response to Issue 1 and the Bituminous Roof Primer discussion.

7. Bituminous Roof Primer Coatings

Product Category Description:

Bituminous roof primer coatings are primers labeled as and formulated exclusively for roofing, that incorporate bitumens. Bitumens are black or brown materials including, but not limited to, asphalt, tar, pitch, or asphaltite that are soluble in carbon disulfide, consist mainly of hydrocarbons, and are obtained from natural deposits or as residues from the distillation of crude petroleum or coal. This new category does not include self-priming bituminous roof coatings, which are considered bituminous roof coatings. Bituminous roof primers are currently regulated in the primer, sealer and undercoater category. However, bituminous roof primers were reported in our 1998 survey under both the bituminous coating category and the primer, sealer, and undercoater category.

It is staff's estimate that bituminous roof primers account for approximately 1 percent of the sales volume and 5 percent of the emissions from the bituminous coatings category, while the sales and emissions represent less than 1 percent and 2 percent, respectively, in the primer, sealer and undercoater category. Combining this information with the data supplied by the Roof Coating Manufacturers Association (RCMA), we estimate that the Bituminous Roof Primers sales are approximately 200,000 gallons per year statewide, complying marketshare is approximately 57 percent, and emissions are approximately 0.2 tons per day excluding the South Coast AQMD (ARB 1999)

Product Use and Marketing:

Bituminous roof primers are sold in California in major home centers, paint stores, and hardware stores. The users range from the professional to the homeowner or do-it-yourselfer. Bituminous roof primers are used to prepare a "cleaned" roof surface for the application of an asphaltic coating. The primer wets out the residual dust and/or metal surfaces in preparation for the bituminous roof coating. Water-based bituminous roof primers can be used under water-based or solvent-based bituminous roof coatings and vice versa. Bituminous Roof Primers are typically applied in the morning and need to cure before applying a bituminous roof coating. One manufacturer claims the cure time is 8 to 24 hours, while another claims 1 to 8 hours.
(Hunter, 2000; Beemer, 2000)

Product Formulation:

The bituminous roof primer category consists of water-based and solvent-based formulations and is currently within the primer, sealer and undercoater category. Our previous draft SCM proposed that they be included in the bituminous roof category. Although the 1998 ARB Architectural Coatings Survey did not specifically survey this newly created category its sales were included under the surveyed categories "bituminous coatings," or "primer, sealer, and undercoater." The VOC contents of products in this category fall within the range of 0 g/l to 500 g/l. The formulations are primarily composed of asphalt, mineral spirits, and fillers for solvent-based coatings, or asphalt, water, clay, and fillers for water-based coatings.

Proposed VOC Limit and Basis for Recommendation:

The proposed 350 g/l VOC limit for bituminous roof primers is technologically and commercially feasible by the January 1, 2003, effective date. District rules have regulated these coatings at 350 g/l for about ten years. As a result, there are numerous complying products on the market. ARB staff estimates that establishing a bituminous roof primer category will result in a slight decrease in anticipated emission reductions from the primer, sealer and undercoater category (moving from 200 g/l to 350 g/l). In creating this new category, staff considered the limited availability of 300 g/l bituminous roof primers in districts with significantly different climate than that of South Coast Air Basin.

Based on ARB staff research and information provided by industry, staff is unaware of bituminous roof primers at 250 g/l or 300 g/l that provide the necessary application and coating characteristics in cold climates that are provided by 350 g/l bituminous roof primers. However, current 250 g/l bituminous roof primers are considered acceptable for applications in locations with climates similar to the South Coast Air Basin. Formulating a 250 g/l bituminous primer requires the use of less solvent that results in unacceptable performance with regard to application and coating characteristics when used in some areas outside of the South Coast Air Basin.

ARB's proposal to create a bituminous roof primer category is based on ARB staff analysis, technical information provided by industry, and discussions with South Coast AQMD staff. As proposed, the bituminous roof primer category would include a provision for annual reporting, which would require manufacturers to submit their annual sales sold within California.

Issues:

1. Issue: We cannot make a bituminous primer that meets the current 350 g/l VOC limit. There are three main problems with the 350 g/l products: the viscosity is too heavy, they don't dry, and you can't put an emulsion over them. Previously, these coatings were around 500 g/l.

Response: Bituminous roof primers in most districts are subject to the primers, sealers, and undercoaters category limit. For approximately ten years, the districts have regulated this coating category at the 350 g/l VOC limit. There are several complying products, which have been on the market for many years. We believe that with modifications to formulations, non-complying bituminous primers can meet the 350 g/l VOC limit. Once the primer is dry, water-based and/or solvent-based coatings can be placed over the top of the primer.


2. Issue: There is a problem with the definitions of roof and bituminous coatings. They were not adequately distinguished as they were in the National Rule.

Response: The ARB staff met with roof and bituminous coating manufacturers to clarify these definitions. We also worked with the RCMA to gather additional data.


3. Issue: The proposed SCM should include a category for bituminous roof primers with a VOC content limit of 500 g/l.

Response: Please see response to Issue 1.


4. Issue: We request a category for bituminous primers. If regulated under the primers, sealers, and undercoaters category, a 200 g/l VOC limit would ban these products.

Response: Please see response to Issue 1.


5. Issue: We request a breakout category for bituminous primers of at least 400-450 g/l.

Response: Please see response to Issue 1.

8. Clear Brushing Lacquer Coatings

Product Category Description:

Clear brushing lacquers are clear wood finishes, excluding clear lacquer sanding sealers, formulated with nitrocellulose or synthetic resins that dry by solvent evaporation without chemical reaction and provide a solid protective film which is intended for application by brush only. This is a new category that is currently included in the general lacquer category in district rules.

It is staff's estimate that clear brushing lacquers account for approximately five percent of the sales volume and three percent of the emissions from the general lacquer category. (ARB 1999; Deft, 1999)

Product Use and Marketing:

Clear brushing lacquers are sold in California to major home centers, paint stores, lumber yards, and hardware stores. The users range from the professional, the homeowner or do-it-yourselfer, to arts and crafts enthusiasts. Clear brushing lacquers are used to finish interior wood surfaces such as furniture, cabinets, paneling, and crafts. In the last decade, wood products are increasingly supplied by the manufacturer pre-finished eliminating the need to apply a finish at home or in the field. In California, a majority of new home or remodeling cabinetry is delivered pre-finished and field finished cabinetry occurs on a limited basis (e.g., custom fabrication).

Product Formulation:

The clear brushing lacquer category consists of solvent-based formulations and falls within the general lacquer category. Although the 1998 ARB Architectural Coatings Survey did not specifically survey this newly created category its sales were included under the surveyed subcategory "clear lacquers." The VOC content of this category falls within the range of 650 g/l to 680 g/l. The formulations are clear coatings composed of synthetic thermoplastic film-forming materials in organic solvents (e.g., ketones and esters) that dry by solvent evaporation. Most lacquers are based on nitrocellulose the film forming material, dissolved in lacquer thinner, the solvent. Nitrocellulose is a cotton-like material derived from mixing the cellulose from trees with nitric acid. These solvent-based formulations have the unique quality of being able to be re-wetted or dissolved when more lacquer or lacquer thinner is applied over existing, dry lacquer. The ability to rewet or re-dissolve lacquer allows for easy repair and recoating without the need to sand between coats or completely remove the existing finish, with chemical solvent borne strippers.

Proposed VOC Limit and Basis for Recommendation:

The proposed 680 g/l VOC limit for clear brushing lacquers is technologically and commercially feasible by the January 1, 2003, effective date because this limit reflects the current VOC content for products in this category. ARB staff estimates that establishing a clear brushing lacquer category will result in a slight decrease in anticipated emission reductions from the general lacquer category, (moving from 550 g/l to 680 g/l). In creating this new category, staff considered the unavailability of 550 g/l brushing lacquers and the transfer efficiency of sprayed lacquer versus a lacquer applied by brush only.

Based on ARB staff research and information provided by industry, staff is unaware of clear brushing lacquer formulations at 550 g/l capable of providing the necessary application and finish characteristics that are available with current 680 g/l clear brushing lacquers. The formulation changes for a 550 g/l spraying lacquer are not acceptable for brushing lacquers. Current 550 g/l lacquers are considered acceptable for spraying applications only. Achieving a 550 g/l brushing lacquer requires the use of strong solvents (e.g., acetone) that result in unacceptable performance with regard to application and finish. Lacquers are typically applied in multiple coats to achieve the desired finish. These 550 g/l formulations bite into previous coats, which results in an unacceptable brush drag and the brush becoming stuck in the previous coat due to solvents softening the prior coat when the second or third coat is applied. With spraying lacquers this is not an issue. Requiring a 550 g/l limit for clear brushing lacquers would essentially shift the current brush application of clear brushing lacquers to spray applied lacquers resulting in lower transfer efficiency. (Deft, 1999)

The transfer efficiency of lacquers applied by brush is essentially 100 percent compared with the typical 65 percent transfer efficiency of a sprayed lacquer. Therefore, applying one gallon of brushing lacquer at 680 g/l (100% transfer efficiency) is equivalent to applying 1.5 gallons of spraying lacquer at 550 g/l covering the same surface area. Thus, applying one gallon of brushing lacquer at 680 g/l results in or 5.7 pounds of VOC and applying 1.5 gallons of sprayed lacquer at 550 g/l that results in 7 pounds of VOC. Consequently, the brush application of a 680 g/l lacquer compared to a 550 g/l sprayed lacquer results in about a 20 percent decrease in emissions. Finally, spray lacquers require greater amounts of cleaning solvent than brushing lacquers, which would result in additional emissions compared to brushing lacquers. (Deft, 1999)

Staff also considered a reformulation approach for a 550 g/l sprayed lacquer. The approach we considered involved displacing traditional VOCs with exempt compounds (e.g., acetone) to determine the necessary volume needed for a 550 g/l sprayed lacquer to achieve the same emissions as a 680 g/l brushing lacquer. ARB staff estimates that 20 percent (by volume) of the traditional VOCs in a 550 g/l spraying lacquer would have to be replaced with exempt compounds to achieve equivalent emissions of a 680 g/l brushing lacquer. Based on ARB staff research and information provided by industry, reformulation of brushing lacquers using acetone, T-buytl or other exempt compounds has not yielded an acceptable product with the necessary application and finish properties.

ARB's proposal to create a clear brushing lacquer category is based on ARB staff analysis, technical information provided by industry and discussions with South Coast AQMD staff. As proposed, the clear brushing lacquer category would include a strict definition and labeling requirements prohibiting thinning. In addition, we are proposing a provision for annual reporting that would require the submission of annual volumes sold in California by manufacturers in order to monitor the category's usage patterns.

Issues:

1. Issue: This category was deemed unnecessary by the South Coast AQMD and was not included in Rule 1113. This proposed category represents another opportunity for industry to sell high VOC coatings, such as lacquers, by relabelling. Despite industry assurances that these coatings will only be brushed and not sprayed, enforcement at the point of sale will be impossible.

Response: The South Coast AQMD chose not to add a clear brushing lacquer category because it felt that the variance approach was more appropriate in order to encourage continued research on the part of the company requesting the variance. On April 20, 1999, the South Coast AQMD hearing board unanimously granted the company a variance for one year and expressed the opinion that a second year would be permitted if the company were unable to formulate a 550 g/l clear brushing lacquer. At the hearing, South Coast AQMD staff testified that there is no other compliant product in the market. The company has been researching 550 g/l brushing lacquer formulations for the past three years and under the variance it committed to continue diligent research towards compliance with a 550 g/l VOC limit.

Our proposal to create a clear brushing lacquer category is based on ARB staff analysis, technical information provided by industry and discussions with South Coast AQMD staff. As proposed, the clear brushing lacquer category would include a strict definition and labeling requirements prohibiting thinning. In addition, we are proposing a provision for annual reporting that would require the submission of annual volumes sold in California by manufacturers in order to monitor the category's usage patterns.

Enforcing the requirement that clear brushing lacquers will only be brushed and not sprayed is similar to current thinning prohibitions contained in existing coating rules. Brushing lacquers are too viscous to be sprayed, they require thinning to enable spray application. Thinning prohibitions can only be enforced via field inspections of coating operations and testing coating samples. Enforcing the "brush only" requirement will also require field enforcement. In addition, the labeling requirements will require the manufacturer to clearly identify on the primary label and application instructions that the product cannot be thinned or sprayed and must be applied by brush only.

9. Faux Finishing Coatings

Product Category Description:

Faux finishes are coatings designed to create special effects such as dirt, old age, smoke damage, marble, or wood grain (Ralph Lauren, 9/98; Flood Company, 1996a). These coatings are generally clear glazes that are tinted or mixed with latex or solvent-based coatings to produce colored glazes (Ralph Lauren, 9/98; Behr, 2/99). Some coating additives or "conditioners" are also used in conjunction with solvent-based or latex coatings to make faux finishes (Flood Company, 1996b; Flood Company, 1997). Japan finishes, which are flat, quick-drying paste colors (T.J. Ronan, 1/4/00), may also be used as faux finishes after thinning (Universal Studios, 1/4/00). Faux finishes do not include general use flat and non-flat coatings, which may also be used in some faux finishing techniques. Sales and emissions information for faux finishes is not available since the ARB's Architectural Coatings Survey did not include a separate category for these products. However, we expect these coatings to represent a minor percentage of the overall sales from architectural coatings.

Product Use and Marketing:

Faux finishing products are sold in paint stores and artist supply stores. These products are used by the general public, graphic artists, motion picture and television studios, and businesses that specialize in decorating with faux finishes.

Faux finishes are generally applied over a household interior semi-gloss or satin/eggshell coatings (Sherwin Williams, 3/98; Golden Artist Colors, 1/4/00). The color of the background coating will combine with the colored glaze, which is the faux finish. A variety of techniques may be used in creating the desired artistic effects. These techniques include additive processes (sponging, ragging, washing) in which a natural sponge, newspaper, paper bags, plastic wrap, etc. are used to add the colored glaze over the base coat. Subtractive processes include sponging-off, ragging-off, and stippling. To perform these processes, an even coat of the glaze is applied over the base coat, and the glaze is then removed with a damp natural sponge, newspaper, plastic wrap, or a stipple brush. Marble, leather, or wood grain finish, may be achieved using various layers and colors of glazes. Tools typically needed for faux finishing techniques include brushes, feathers, paper bags, graining tools, and thin plastic wrap. (Ralph Lauren, 9/98; Sherwin Williams, 3/98)

Faux finishes are generally clear glazes that are designed to be tinted, or mixed with latex coatings (or solvent-based coatings in the case of solvent-based faux finishes) before application. The mixture's ratios will vary with the color and degree of opaqueness desired. In some cases, the products may be used "as-is" when a clear coating is desired. Japan finishes are different in that they are high-solids pastes that may be thinned down prior to use (Universal Studios, 1/4/00).

Product Formulation:

As mentioned above, faux finishes are generally clear glazes prior to tinting or blending with other coatings, and thus contain resins, solvents, and water (in latex products), but no pigments. These products may have a higher concentration of slower evaporating solvents than typical household coatings in order to extend the "open" (wet) time. The longer "open" time allows the coating to be manipulated to create the desired artistic effects. After tinting or mixing with other coatings, the formulations will vary widely. Generally, when water-based faux finishes are mixed with household latex coatings, their VOC content would be expected to drop. Solvent-based faux finishes may be mixed with solvent-based coatings and mineral spirits (Sherwin-Williams, 1/99), which may increase or decrease the overall VOC content depending on the proportions used. Japan finishes are reportedly thick solvent-based alkyd coatings with a high concentration of pigments. These are reportedly thinned with solvent prior to use as faux finishes (Universal Studios, 1/4/00), which would increase their VOC content.

Proposed VOC Limit and Basis for Recommendation:

We are proposing a 350 g/l VOC limit for faux finishes, effective January 1, 2003. This VOC limit is technologically and commercially feasible as demonstrated by the complying water-based products currently on the market (Sherwin Williams, 3/98; Behr, 1/19/00). The U.S. EPA's national architectural coatings rule provides a 700 g/l VOC limit. However, we believe the proposed 350 g/l VOC limit is appropriate because we are aware of faux finishes currently on the market that are below this VOC level. The proposed VOC limit is also consistent with the South Coast AQMD's Architectural Coatings rule.

Manufacturers of noncomplying faux finishes have various reformulation options. Solvent-based products could switch to a water-based formulation or investigate the use of exempt VOC solvents. Water-based products will need to reduce the amount of solvents, or increase the amount of resin in the formulation. These changes may require manufacturers to investigate different solvents and resin systems, similar to the changes necessary for other general use flat and non-flat coatings. However, the 350 g/l VOC limit is substantially higher than the 100 and 150 g/l VOC limits proposed for general use flat and non-flat coatings, providing for a longer "open time" for these products.

Issues:

1. Issue: The ARB should create a 700 g/l VOC limit consistent with the
U.S. EPA's national architectural coatings rule. To date, there has not been an identifiable way to reformulate these products to achieve a lower VOC content while maintaining the characteristics required for acceptable use, such as an extended open time.

Response: As stated above, we are aware of existing faux finishes that have a VOC content below the proposed 350 g/l VOC limit. One of these products has an open time of about 15 minutes (Sherwin Williams, 3/98), which is comparable to some higher VOC faux finishes (Sherwin Williams, 1/99; Golden Artist Colors, 1/4/00). We also note that a shorter open time can be accommodated by working in smaller sections.


2. Issue: It is unfair to calculate the VOC content of our water-based faux finishes on a less water basis. On a formula basis, the calculated VOC of our product can range up to 340 g/l. However, because the products are water-based, the VOC less water calculation results in a range of up to 700 g/l. Removing water to calculate the VOC content is unnecessary because achieving these effects depends upon creating transparent layers. The addition of water to these coatings is required for optimum performance and does not result in the application of greater volumes of material to offset the resulting lack of opacity. Not only is there no benefit to imposing this restriction on water-based products, the requirement for removing water from the calculation will likely result in less use of water-based finishes and greater total VOC emissions.

Response: We are aware of water-based faux finishes that comply with the proposed 350 g/l VOC limit, less water, and are designed to create transparent layers. We expect that these products will result in less emissions than higher VOC water-based faux finishes.

10. Fire-Resistive Coatings

Product Category Description:

Fire-resistive coatings, also known as fireproofing materials or fire-resistant coatings, are used to bring building and construction materials into compliance with federal, State, and local building code requirements. These coatings must be tested and rated by an approved testing agency for their ability to protect the structural integrity of steel and other structural materials by increasing the fire endurance. The testing is done using time-temperature criteria of ASTM Designation E 119-98, "Standard Test Methods for Fire Tests of Building Construction Materials." This method is virtually identical to Universal Building Code (UBC) Method 7-1, as specified in the California Building Code. This category is proposed to be included in the SCM for the first time.

The National Architectural Coatings Rule combines fire-retardant and fire-resistant coatings into one category. We are proposing two separate categories because the coatings work in different ways, and the effectiveness of the coatings in protecting substrates against fire are measured by different methods. Fire-retardant coatings limit the spread of flame on the surface of interior building materials, while fire-resistive coatings protect the integrity of structural elements by limiting the penetration of flame.

The South Coast AQMD created a category for fireproofing coatings in its 1996 amendments to Rule 1113. This category was requested by industry to be separate from the fire-retardant coating category. The reasons the South Coast AQMD added this category were that the mode of action and the test methods differ for fire-retardant and fireproofing coatings. The definition for fireproofing coatings in the South Coast AQMD rule, however, did not include interior structural materials (South Coast AQMD, 1996). The ARB staff has independently concluded that two separate categories for fire-retardant and fire-resistive coatings are needed.

The 1998 ARB Architectural Coatings Survey did not include a category for fire-resistive coatings. Therefore, we have no estimate of sales or emissions. However, our investigation has shown that the fire-resistive coating category is very small and specialized. Based on the estimated 4,000 gallons of solvent-based product sold yearly in the South Coast Air Basin
(South Coast AQMD, 1996), we estimate that statewide sales are less than 10,000 gallons per year.

Product Use and Marketing:

Fire-resistive coatings are specialty products applied by contractors. They are available from distributors or direct from the manufacturer. They are used in public buildings such as schools, hospitals, nursing homes, factories, high-rise office buildings, and sports complexes. Fire-resistive materials are tested with ASTM E 119, "Standard Test Methods for Fire Tests of Building Construction and Materials." The entire structure, such as a firewall, coated with the fire-resistive material is placed in a furnace and the time required to reach critical parameters is measured. For example, in firewalls, the time to reach "burn through" of the coating is measured. In structural steel coated with fire-resistive materials, the failure criterion is the internal temperature of the steel, based on the fact that the structural integrity of steel fails at 1200o F. The fire rating is the time in hours required to reach the critical parameter of the material being measured (Bratcher and Alvarez, 1996).

The California Building Code specifies fire-resistive ratings for various types of construction with different occupancy levels, based on varying degrees of public safety. For example, Type I construction (structural elements of steel, iron, concrete, or masonry) must have 2-hour fire-resistive ratings for floors and roofs, while exterior bearing walls must have a 4-hour fire-resistive rating. Type V structures (homes) have 1-hour fire-resistive ratings for these same elements (California Building Code, 1998).

Professional architects and engineers use the Underwriters Laboratories (UL) Inc. Fire Resistance Directory to help them design buildings with the appropriate structural fire-resistive designs and materials. The structural element coated with the fire-resistive material is listed in the directory as "UL design numbers" for fire resistance, which gives the number of hours or the depth of penetration of the fire resistance. The thickness of the fire-resistive coating that must be applied to a given structural element, which will give a certain hourly rating, are derived from these UL fire resistance designs. There are design values for, as examples, floor assemblies, roof assemblies, and walls. Within these categories, the thickness of the fire-resistive material depends on, for example, steel size and shape, type of concrete, and thickness of concrete
(Grace, undated). There are books of these design numbers available for the large variety of structural elements used in construction (Woods, 1999).

For example, the California State Fire Marshal lists fire-resistive designs such as structural members and walls/partitions. Some examples of fire-resistive materials include expansion joints and head-of-wall/wall-to-wall joint systems. Each of these materials is tested using ASTM Designation E 119 (UBC 7-1). Other materials such as acoustical materials and interior coating materials are tested for flame spread index with ASTM E 84 (State Fire Marshal, 1999).

Thus, the building codes determine the degree of fire resistance needed, and the test method that is used to evaluate the fire resistance of the coating. Registered architects or professional engineers must determine which hourly rating, UL design, and thickness of fire-resistive coating is needed for a building project, and these decisions must be reviewed and approved by the building code official (Grace, undated). However, manufacturers can choose to test their fire-resistive coatings at any of several testing laboratories approved by the California Fire Marshal and other building code officials. These coatings and the results of the testing data must be registered with the State Fire Marshal (Woods, 1999).

Product Formulation:

Fire-resistive coatings are generally of three types: gypsum-based cementitious coatings, fibrous (i.e., treated paper) coatings, and intumescent mastic coatings. The first two are solid materials, sprayed as a slurry, which insulates the structural element with exposed air pockets. Intumescent coatings form thick, puffy foam when exposed to high heat, which insulates the substrate against further intrusion of the flame.

Fire-resistive coatings are applied onto or impregnated into a substrate primarily for protective purposes, and they do not necessarily form a film. One commenter on the National Rule requested clarification about the applicability of gypsum or cement-based, spray applied fire-retardant products that are applied to steel building surfaces during construction or renovation. The U.S. EPA confirmed that these cementitious fire protection products, that are often spray-applied as a thick slurry up to 3-1/2 inches thick and do not form a film as do other opaque fire-retardant materials, should be included in the fire retardant/resistive category (U.S. EPA, 1998b).

The thin film intumescent coatings have become more popular for structural steel with architects in recent years because of their appearance and design options that are not possible with the thicker films. Whereas with traditional material, where one to two inches of fire-resistive material might be required, only 1/16th of an inch of the intumescent coating is needed to provide the same fire rating. The trade-off is that intumescent coatings cost more than traditional coatings (Bratcher and Alvarez, 1996).

Fire-resistive mastic coatings are usually solvent-based for exterior use and water-based for interior use. Fire-resistive coatings must be capable of withstanding abrasion, impact, freezing, and thawing, and must not form dust, flakes, cracks, or delaminate. They must withstand weathering, ultraviolet exposure, and vibration (Albi, undated). Water-based formulations are more challenging to formulate with the same hardness and exterior application properties under wet conditions (South Coast AQMD, 1996).

Some manufacturers recommend the use of a primer over steel, while others recommend that primer not be used, prior to the application of a fire-resistive coating. Some gypsum-based coatings can be used on the interior of structures, while others made with Portland cement can be used for exterior applications. Some coatings can be painted, but the painted surfaces must meet the surface flammability criteria of ASTM Method E 84. Sealers are usually not needed over these fire protection products (Grace, undated).

Proposed VOC Limit and Basis for Recommendation:

The proposed VOC limit of 350 g/l is technologically and commercially feasible by the January 1, 2003, effective date based on: the technology assessment and limit in effect in the South Coast AQMD; and the fact that no variances from the 350 g/l limit have been requested from the 350 g/l limit in South Coast AQMD Rule 1113. The proposed limit reflects current technology. We do not expect that reformulation will be required at this time.

The National Rule VOC limit for clear fire-retardant/resistive coatings is 850 g/l. The category appears in other states' rules. The U.S. EPA does not provide a rationale for this VOC limit in the preamble to the National Rule or the Background Information Document (U.S. EPA, 1998a; U.S. EPA, 1998b).
 

During our technology assessment, some manufacturers requested a VOC limit for fire-resistive coatings of 420-430 g/l. Manufacturers claim that this limit is needed for exterior mastic coatings because they must withstand more rigorous weathering than interior coatings. In contrast, the interior mastic coatings are very low in VOC, but do not withstand the weathering criteria. However, these manufacturers have not provided test data, product literature, or VOC content data to support the need for a higher limit.

We recommend that the VOC limit for fire-resistive coatings be 350 g/l, the same as in the South Coast and Antelope Valley Districts. This limit has been successfully in effect since 1999 in the South Coast AQMD. We concur with the technology assessment of the South Coast AQMD in which the manufacturers who requested the category claimed that they could achieve the 350 g/l limit by January 1, 1999. To date, the South Coast AQMD has received no applications for variances from manufacturers of fireproofing coatings; therefore coatings sold in the South Coast AQMD with a VOC content higher than 350 g/l would be in violation of Rule 1113 (Berry, 2000).

11. Floor Coatings

Product Category Description:

Floor coatings are opaque coatings labeled and formulated for application to flooring including, but not limited to, decks, porches, steps, and other horizontal surfaces that may be subject to foot traffic. Due to their exposure to impacts and abrasion, floor coatings usually possess good adhesion qualities. These coatings are used in a variety of commercial and industrial applications, as well as residential applications. (Note: Clear coatings recommended for floors are not included in the floor coating category. Varnishes and lacquers that are recommended for use on wood floors are considered clear wood finishes and are subject only to the VOC content limit for their respective categories.) (South Coast AQMD, 1999)

The 1998 ARB survey shows that 1996 sales in California were 657,393 gallons for water-based formulations, or about 57 percent of the total floor coatings sales. The sales weighted average VOC content for water-based floor coatings is 164 g/l. The sales weighted average VOC content of the 493,568 gallons of solvent-based formulations was 197 g/l, which is less than the proposed 250 g/l VOC limit (ARB, 1999).

Table VI-10 below summarizes our estimate of sales and VOC emissions from the floor coatings category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

Typical uses of floor coatings include a variety of commercial, industrial, and residential applications. These coatings are designed and recommended for application to either wood or concrete flooring including, but not limited to, residential and commercial garage floors, commercial parking garages, warehouse floors and residential and commercial wood floors, decks, porches, and steps. Many floor coatings are resistant to many solvents, chemicals, and gasoline and oil spills. Floor coatings may also be formulated to have tire mark releasing properties when using an appropriate cleaner. Floor coatings are sold in hardware stores, at home improvement centers, and paint stores.

Appropriate surface preparation is essential to obtain adequate adhesion of floor coatings. Typical recommended preparation is to remove all dirt, grease, oil, efflorescence, waxes and other foreign matter from the surface to be coated. On glossy surfaces, the surface should be deglossed to allow for better adhesion of the coating. When coating raw/bare smooth cured concrete, it is commonly recommended that the surface first be cleaned and lightly etched with an acid based solution. It may then be necessary to completely neutralize the substrate (above and below the surface) and let it dry. Etching a smooth concrete surface will increase the surface profile, resulting in better adhesion. Substrate alkalinity is also often a critical factor that may affect adhesion and overall performance of certain floor coating formulations. Therefore, it is often recommended that concrete be allowed to cure for at least 28 days prior to coating.

Product Formulation:

Typically, the coating system includes a primer and topcoat or a two-component single coat coating. Although formulated using a number of resin systems, the highest performing floor coatings are based on epoxy or polyurethane systems. Over the past five years, the most significant progress in floor coatings has been the development of zero-VOC, two-component, aliphatic polyurethane coatings, and two-component epoxy coatings. Regardless of the resin system employed, the use of a primer/sealer is often recommended to enhance adhesion. The newer polyurethane technology is based on both 1-part and 2-part coatings, with numerous products being offered as completely solvent-free systems. (South Coast AQMD, 1999)

There have been recent developments in water-based polyurethane coatings for high performance floor applications. Several paint manufacturers have commercialized two-component water-based polyurethane systems for heavy-duty concrete floor protection. These systems are virtually odor free, have 0 g/l VOC content, and provide excellent wear resistance. These formulations are based on water-dispersible aliphatic polyisocyanates and water-dispersible polyester polyols. (MPC, 1996)

Two component formulations may be subject to degradation from ultra violet (UV) exposure. For example, epoxies may chalk from UV exposure. The chalking does not effect the durability of the finish, only the appearance. There are, however, UV stabilized formulations available at an additional cost. Use of an additional topcoat is also an alternative to improve UV performance.

Proposed VOC Limit and Basis for Recommendation:

The proposed SCM recommends a VOC limit of 250 g/l for floor coatings. The proposed VOC limit is technologically and commercially feasible by the January 1, 2003, effective date based on our review of the literature and trade journals, complying marketshare, and information provided by manufacturers and resin suppliers.

The proposed limit of 250 g/l differs from the previously proposed limit of 100 g/l. This is due primarily to enforcement concerns, especially for California districts with fewer enforcement resources than the South Coast AQMD. (The South Coast AQMD's Rule 1113 has a floor coating limit of 100 g/l, effective July 1, 2002.) Many coatings in other categories go on horizontal surfaces subject to foot traffic, such as industrial maintenance coatings, stains, and waterproofing wood sealers. These coatings categories have proposed limits of 250 g/l. We recognize that there are similarities between floor coatings and these other categories. Manufacturers could re-label products rather than reformulate them if the VOC limit is different among these categories and floor coatings. Accordingly, for improved enforceability outside of the South Coast AQMD, the proposed SCM has a floor coating limit of 250 g/l. This also has the effect of allowing for more complying single component floor coatings for residential use.

Survey Results

Table VI-11 below summarizes our estimates of the number of products that were marketed in 1996 that complied with the proposed VOC limit and their associated marketshare for that year. No the emission reductions would be realized if the limit were implemented in the non-South Coast AQMD portions of the State, because floor coatings currently are subject to the default VOC limit of 250 g/l, since there is no floor coatings category in most district architectural coatings rules.

Table VI-11 Floor Coatings**
Proposed VOC Limit (g/l)	Number of Complying Products	Complying Marketshare (%)	Emission Reductions (excluding South Coast AQMD) (tons/day)
250	373	84.8	0

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.


Literature Search

As a part of our analysis, ARB staff gathered information on numerous floor coating systems that comply with the proposed limit.

For example, Air Products and Chemicals, a raw material supplier of architectural and high performance resins, is currently marketing the ADURA™ Polyols line, which is recommended for a variety of floor uses, including gymnasiums and industrial facilities. The two-component, aliphatic polyurethane formulations also provide excellent coverage. The lower-cost ADURA™ 50 is specifically recommended for concrete coating formulations. (South Coast AQMD, 1999)

The Sherwin-Williams Company markets a 100 percent solids, self-leveling epoxy coating called "ArmorSeal 650 SL/RC," which is a two-component, zero-VOC floor coating. They also have a zero-VOC primer recommended for use with the topcoat, as well as additional formulations of zero-VOC floor coatings. (South Coast AQMD, 1999)

Coatings Resources Corporation (CRC), a Southern California coating manufacturer also manufactures several zero-VOC floor coatings. These include their CR-10, CR-11, CR-12, and CR-13 coatings, all 100 percent solids, epoxy or epoxy novolac formulations. In addition, CRC has single-component acrylic floor coatings with VOC contents of less than 50 g/l that are recommended for residential and commercial applications. (South Coast AQMD, 1999)

Madison Chemical Industries, Inc. has several high performance, zero-VOC, two-component coatings recommended for a variety of industrial and general maintenance uses, including flooring. Their Tufsheen II is a two-component aliphatic polyurethane coating that complies with the proposed limit for floor coatings. (MCI, 1999)

Hart Polymers, Inc., a supplier of raw materials and high performance coatings, also has a variety of water-based, zero-VOC, floor coatings. HP-100 is a two-component aliphatic urethane, offering excellent coverage and a pot life. Hart Polymers also markets zero-VOC, single-component floor coatings in both aliphatic polyurethane and acrylic/aliphatic polyurethane dispersions, labeled HP-140 and HP-130, respectively. These single component floor coatings can also be used in residential environments. (South Coast AQMD, 1999)

Poly-Carb, Inc., a company based in Cleveland, Ohio, has a variety of high build, 100 percent solids, two-component floor coatings, with specialty formulations available for a variety of chemical exposures. Specifically, the MARK-64.1 is a heavy duty floor coating recommended for wastewater and water treatment plant floors, industrial and manufacturing floors, laboratories, kitchens, food processing areas, high traffic areas, splash zones, and areas subject to corrosive acid and alkali spills. (South Coast AQMD, 1999)

Seal-Krete, Inc., a company based in Auburndale, Florida, markets several floor coatings that comply with the proposed VOC limit. Their zero-VOC product, Proformance Skid-Proof (PSP) is a water-based, acrylic-based, quartz, non-cementitious anti-skid coating. PSP is neutral in color and can be tinted by adding a desired color of exterior gloss acrylic, acrylic floor enamel or industrial acrylic enamel coating. When fully cured, it is hard and tough; yet flexible, with a high tensile strength, is waterproof, weather-resistant, impact resistant, salts resistant and chlorine resistant. PSP may be applied by trowel or spray hopper (a brush and roll down formulation is also available with 40 g/l VOC). During and after application before it has time to dry, PSP may be cleaned up with soap and water. PSP is used as a decorative, protective coating for long-term preservation of various surfaces including: concrete, wood, plywood, primed metal and styrofoam. PSP can be used on interior and exterior vertical and horizontal surfaces including traffic areas such as: walkways, patios, stairs, pool decks, balconies, ramps, and driveways. (Seal-Krete, 1999)

Vianova Resins, Inc., has developed floor coatings formulations (0 - 250 g/l VOC) based on their BECKOPOX epoxy resins and curing agents. These water-based coatings offer excellent adhesion, fast drying, high coverage rate, smooth flow and leveling and excellent lapping. (BECKOPOX, 1999)

Vianova Resins, Inc., has also developed their air-drying RESYDROL® AY466 high gloss enamel, an acrylic-modified, core-shell, alkyd emulsion formulation (72 g/l VOC). This high performance coating offers excellent application properties, superior scratch resistance, quick drying, and excellent weatherability, chemical resistance, and adhesion to wood. (Vianova Resins, 1999)

Other companies offering floor coatings that comply with the proposed 250 g/l limit include Polycoat Products, Ameron, United Coatings, Pacific Polymers, Tnemec, and Pittsburgh Paints. (South Coast AQMD, 1999)

Issues:

1. Issue: Two component coatings cost too much and are too difficult for the average homeowner to use.

Response: Many of today's two component coatings offer an extended pot life (up to 8 hrs) which greatly enhances their application. To assist homeowners, local hardware stores offer "How-To" clinics on many subjects. Sales representatives from one of the largest west coast retail hardware chains have indicated a positive response from homeowners regarding their use of two component floor coatings. In addition, although two component floor coatings will provide the highest performance, there are compliant single component coatings available with acceptable performance levels that are easier to use.


2. Issue: Two component coatings are too dangerous for the average homeowner to use.

Response: The moisture cured, two component, and prepolymer plus catalyst polyurethane coatings that contain free isocyanates can be hazardous and are only recommended for professional application.

There are other types of polyurethane coatings (oil modified, for example) that are available for the homeowner that have no free isocyanates. Two component epoxies do not have this type of hazard associated with their use. In addition, although two component floor coatings will provide the highest performance, there are compliant single component coatings available with acceptable performance levels.

12. Flow Coatings

Product Category Description:

Flow coatings are products designed for use by electric power companies or their subcontractors to maintain the protective coating systems on utility transformer units. These coatings are extensively thinned with solvent to allow them to run down into electric utilities' transformer radiator fins to create a thin, even film that will not interfere with heat exchange. This method of application is necessary because it is difficult to apply paint in between the radiator fins by other painting methods (PG&E, 1/3/00a). According to one manufacturer, these coatings cannot be thinned down with water because they would dry too quickly in warm temperatures and would not flow out into a thin, even film (Triangle Coatings, 12/10/99).

We are proposing to add a new category for flow coatings in the SCM. These coatings are not regulated in district architectural coatings rules as a separate category (but instead are subject to the industrial maintenance category). However, as explained below, we believe that a new category and VOC limit for these products is justified. In addition, the U.S. EPA's national architectural coatings rule contains a separate category and VOC limit for these products.

No flow coatings were reported in the ARB's Architectural Coatings Survey. However, one manufacturer subsequently provided sales volumes in California, and VOC content information, indicating that these products contribute VOC emissions less than 0.01 tons per day (TPD) statewide, excluding the South Coast AQMD.

Product Use and Marketing:

Flow coatings are highly specialized coatings used by electric power companies or their subcontractors, and are not available to the general public through typical retail outlets. As mentioned above, these coatings are designed to produce a thin film on transformer radiator fins that will not impede heat exchange. These coatings are applied with a hose over the top of transformer radiators, and allowed to run down the fins (Triangle Coatings, 12/10/99; PG&E, 1/3/00b). The excess coating drips into a collection basin at the bottom of the radiator, and a pump then pulls the excess coating from the basin where it is again applied over the top of the radiator fins until all of the radiator surfaces are coated. The excess coating in the basin can be recovered.

Product Formulation:

We are only aware of one flow coatings manufacturer that sells these products in California. This manufacturer currently produces a water-based flow coating developed specifically for PG&E, that is thinned extensively with butyl cellosolve to allow for the desired flow-out in warm weather conditions. Due to confidentiality concerns, we cannot reveal further details about this formulation.

Proposed VOC Limit and Basis for Recommendation:

We are proposing a 420 g/l VOC limit for flow coatings, effective January 1, 2003. This is slightly lower than the 450 g/l VOC limit in the U.S. EPA's national architectural coatings rule. However, the proposed VOC limit is technologically and commercially feasible because it essentially places a cap on the VOC content of existing products sold in California. We believe this proposed VOC level is appropriate because we are not aware of any lower VOC products or existing technology that would allow for compliance with a lower VOC limit. Increasing the solids level, or the amount of water, would not allow for the flow out needed in this application. These products would generally be subject to the 50 g/l VOC limit proposed for industrial maintenance coatings if they are not provided with a separate category. Finally, as mentioned above, the emissions from these products are less than 0.01 TPD statewide, excluding the South Coast AQMD.

13. High-Temperature Coatings

Product Category Description:

High-temperature coatings are high performance products formulated, recommended, and designed for use on the surface of materials exposed continuously or intermittently to temperatures above 204°C (400°F). [This category differs from industrial maintenance coatings which are designed for repeated exposure to temperatures above 121°C (250°F)].

Table VI-12 below summarizes our estimate of sales and VOC emissions from the high-temperature coatings category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.

A high-temperature coating that also meets the definition of "metallic pigmented coating," containing at least 48 grams of elemental metallic pigment per liter (0.4 lb/gal) of coating as applied (see Section B-10), is subject only to the proposed 500 g/l VOC limit for "metallic pigmented coatings." A new category for "temperature-indicator safety coatings" (see Section A-286 ) is being proposed as a separate category from the "high-temperature coatings" category. Section 3.2 of the proposed SCM has been revised to clarify that these categories are not subject to the most restrictive limit.

Product Use and Marketing:

Typical uses of high-temperature coatings include the protection of metal surfaces of furnaces, stacks, power plants, heat exchangers, boilers, exteriors of reactors, oil refineries, chemical plants, piping, exhaust mufflers, as well as other surfaces exposed to high temperatures.

Surface preparation and coating application methods should be similar to those for the more typical "industrial maintenance coatings" (see Section A-142). Manufacturer recommendations may include surface preparation by abrasive blasting or other methods, and application of the coating within a specified time period to avoid new rust. Application may be by spray equipment, especially for larger jobs. Some coatings may also be applied by brush or roller.

High-temperature coatings are sold by independent coating retailers and brand-name sales outlets that also sell the more typical "industrial maintenance coatings" (see Section A-14 12), however, there are fewer high-temperature coating products available and hence market availability is likely to be more limited.

Product Formulation:

Current high-temperature coatings are predominately solvent-based, constituting 99 percent of the sales volume reported in the 1998 ARB survey. High-temperature coatings may be formulated with resins containing silicon compounds, while containing less organic compounds that tend to deteriorate at higher temperatures. Traditional moderate temperature heat-resistant coatings include solvent-based silicone alkyd and silicone acrylic formulations, sometimes with zinc or aluminum pigments. Higher temperature heat-resistant coatings include solvent-based pure silicone formulations. Some heat resistant coatings require heat curing upon restarting (and thus reheating) the painted equipment. Newer heat-resistant coatings include a low-VOC (less than 250 g/l) siloxane formulation that is heat resistant up to 1112° F (600° C).

Proposed VOC Limit and Basis for Recommendation:

The proposed VOC limit is 420 g/l, effective January 1, 2003. The proposed limit is technologically and commercially feasible, by the effective date, based on our review of complying marketshare, currently available coatings, the Harlan Associates Study, and the 420 g/l VOC limit currently in effect in eight district rules.

As indicated in Table VI-13 below, 52 percent of the market already complies with the proposed limit. According to the ARB 1998 survey, a notable portion of the market consists of coatings with VOC content in the range from 450 to 500 g/l, which is slightly higher than the proposed VOC limit of 420 g/l. Coatings in this range may have the option to comply by adjusting their resins/formulations, tightening quality control, increasing solids content, or substitution of solvents with exempt compounds, such as Oxsol 100™ or the potential future exempt solvent tertiary-butyl acetate (TBAc™).

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

The proposed limit is already in effect in eight districts, with a ninth district (the South Coast AQMD) to have the limit in effect on July 1, 2006. In the eight districts the VOC limit will remain the same, resulting in essentially no reduction in the non-South Coast AQMD portion of the State with the proposed SCM limit. To allow time for the unique temperature-indicator safety coatings to comply with the 420 g/l limit, the South Coast AQMD has provided an interim limit of 550 g/l for the period from July 1, 2002, to July 1, 2006.

The following summarizes VOC limits in the U.S. EPA regulation for high-temperature and related coatings.

* Grams VOC per liter of coating, less water and exempt compounds.
** "Heat-reactive" coatings are phenolic-based coatings that require heat for curing
(see Section B-9).

Harlan Associates Study

The Harlan Associates Study (Study) included testing of three high-temperature coatings with VOC contents below the 420 g/l limit, and two high-temperature coatings with VOC contents above the 420 g/l limit. The Study indicated that the performance of the high-VOC coatings and the low-VOC coatings was essentially equivalent for a number of critical areas. The tests included evaluations of coating heat resistance, stability, hardness, adhesion, dry-to-touch time, abrasion resistance, and impact resistance.

Issues:

1. Issue: The limit should initially be 550 g/l (as in South Coast AQMD rule), with the limit dropping to 420 g/l in the year 2006. For safety reasons, an oil refinery must use certain
high-temperature indicator coatings, as required by current equipment designs. An initial limit of 550 g/l would allow current coatings to be used, while other products for high-temperature service are evaluated.

Response: A new category for "temperature-indicator safety coatings" is being proposed for this unique type of coating (see Section A-286). The limit for the new category is proposed to be 550 g/l, effective January 1, 2003. A limit of 420 g/l is proposed to be retained for other high-temperature coatings.

14. Industrial Maintenance Coatings

Product Category Description:

Industrial maintenance coatings are high performance products designed for use to protect the surface of structures and other stationary equipment (except floors) exposed to one or more of the following extreme environmental conditions:

1. Immersion in water, wastewater, or chemical solutions (aqueous and non-aqueous solutions), or chronic exposure of interior surfaces to moisture condensation;
2. Acute or chronic exposure to corrosive, caustic or acidic agents, or to chemicals, chemical fumes, or chemical mixtures or solutions;
3. Repeated exposure to temperatures above 121oC (250oF). [However, if a coating is formulated, recommended, and used for applications to surfaces and materials exposed continuously or intermittently to temperatures above 204°C (400°F), the coating would fall into the category of "high-temperature coating" (see Section A-13)].
4. Repeated (frequent) heavy abrasion, including mechanical wear and repeated (frequent) scrubbing with industrial solvents, cleansers, or scouring agents; or
5. Exterior exposure of metal structures and structural components.

These coatings include primers, sealers, undercoaters, intermediate coats, and topcoats. Industrial floor coatings are not in the "industrial maintenance coatings" category, but are included in the "floor coatings" category with a VOC limit of 100 g/l.

A coating meeting the definition of "industrial maintenance coatings" may also meet the definition of "high-temperature coatings," "metallic pigmented coatings" (e.g. anti-rust primers formulated with zinc dust), "pre-treatment wash primers," or "temperature-indicator safety coatings." Section 3.2 of the proposed SCM has been revised to clarifyies that these categories are not subject to the proposed limit for industrial maintenance coatings.

Some categories of coatings meet both the definition of "industrial maintenance coating" in the SCM and another coating category as defined in the U.S. EPA's national rule. In the national rule these "national categories" coatings are treated as separate categories with less stringent VOC content limits. In the SCM, only three of the "national categories" are treated as separate categories - "antenna coatings," "anti-fouling coatings," and "flow coatings." Section 3.2 of the proposed SCM clarifies that these categories are not subject to the proposed limit for industrial maintenance coatings. These categories are discussed in Sections A-3,4, 5,
and 10 12.

The SCM does not consider the remaining "national categories" separately, so the VOC limit for "industrial maintenance coatings" would generally apply to these categories (as discussed in Section C of this Chapter).

In the South Coast AQMD rule, two other coating categories were separated from the industrial maintenance coating category (Rule 1113 - "Architectural Coatings," amended May 14, 1999). These categories are "chemical storage tank coating" and "essential public service coating." As defined in the South Coast AQMD rule, a "chemical storage tank coating" (at 420 g/l, interim limit) is a coating used as an interior tank lining for the storage of oxygenated solvents, oxygenated solvent mixtures, or acid based products. As defined in the South Coast AQMD rule, "essential public service coating" (at 340 g/l, interim limit) is defined as a protective (functional) coating applied to components of power, municipal wastewater, water, bridges and other roadways; transmission or distribution systems during repair and maintenance procedures." Instead of using the South Coast AQMD approach, the SCM would generally keep chemical storage tank and essential public service within the "industrial maintenance coating" category. However, to allow time for essential public service agencies to complete their separate technology assessment and their administrative processes before low VOC coatings can be used, the proposed compliance date is extended until January 1, 2004. This extension would avoid the need to provide essential public services a higher VOC limit until they receive approval to use complying coatings. Coatings for lining tanks and for aggressive exterior exposure are available with VOC contents below 250 g/l, including several with zero VOC (see references - "Example Low-VOC Coatings for Tank Linings" and "Example Low-VOC Coatings for Aggressive Exterior Exposure").

Table VI-14 below summarizes our estimate of sales and VOC emissions from the industrial maintenance coating category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

Industrial maintenance coating is a generic term for a variety of high performance coatings used in areas with harsh environmental conditions. Typical users include onshore and offshore oil and gas production, refineries, petrochemical production and processing, marine (except boats, ships, and other watercraft), pulp and paper mills, bridges, manufacturing facilities, water supply facilities, and waste water treatment facilities. Coatings may be used for specific purposes. More specific examples include: rust prevention for steel bridges exposed to coastal air and weathering; chemical protection of the interior of petroleum storage tanks and piping; corrosion prevention of the interior of tanks (such for potable water or sewage) at essential public services; protection of equipment at pharmaceutical manufacturing and food processing plants; and protection of industrial concrete surfaces (except floors). Some industrial maintenance coatings are intended for limited types of use while others are versatile and multifunctional. The coating may be recommended for heavy, moderate, or light industrial environments.

Industrial maintenance coatings do not include coatings used for shop application, such as for the manufacture of parts or products in a factory, nor coatings applied to vehicles, such as railcars, ships, boats, and airplanes (see definition of "architectural coating" in Section 2.5 of proposed SCM). For coating operations such as these, districts may have separate rules regulating the use and VOC content. Also, districts may, through their permitting process, impose facility-specific permit conditions for coating and related operations.

Industrial coatings are restricted to industrial professional users, as prescribed by the coatings manufacturer. Marketing methods vary, in the way coatings get from the manufacturers to the end-users at industrial facilities. Independent coating retailers may provide specialized sales and services for industrial customers. The services may include field evaluations and consultation to determine appropriate coatings, available from a variety of manufacturers, and to facilitate proper coating selection and application. These independent retailers may sell certain coatings (non-industrial) to the public as well. Other independent retailers may sell primarily to the public consumer, and may provide industrial coatings on a limited basis or not at all. Some brand-name outlets market only its own proprietary line of coatings or predominantly its own line with supplemental coating products from other manufacturers. The brand-name companies may have large regional sales centers that provide consultation services and may sell their entire line of coatings for a multitude of purposes, including industrial maintenance. A manufacturer of industrial maintenance coatings, such as smaller companies with limited market distribution, may directly market and consult with industrial end-users. The industrial end-user may either have its own painting/maintenance staff or hire painting/maintenance contractors. [Note: Coatings in the "rust-preventative coatings" category are intended for residential non-industrial use. Rust-preventative coatings may not be used for "extreme environmental condition" purposes in industrial facilities, unless the rust preventative coating complies with the 250 g/l VOC limit for industrial maintenance coatings. (see Section A-23)]

Because of the variety of uses and types of coatings, the recommended surface preparation and application methods vary. For surface preparation in some situations, such as rust prevention of steel structures, abrasive blasting may be required to meet industry-standard surface condition specifications. Some abrasive blasting operations need containment equipment to reduce the spread of abrasives and debris beyond the immediate area. Concrete surfaces to be submerged may need abrasive blasting or etching with muriatic acid. In highly demanding environments, thorough surface preparation is crucial to the successful performance of the coating. In other situations, high-pressure water blasting, handtool cleaning, or wire brushing may be appropriate. Less demanding situations may require clean and dry surfaces with appropriate primers or base coats.

Application methods vary, from conventional air spray, airless spray, roller, spreader, squeegee, brush, or various combinations, depending on the coating and equipment to be coated. For larger jobs, spray application may be desirable because of faster application and less overall labor costs. Sometimes industrial-grade spray equipment and professional protective gear/clothing, including respirators, may be needed. Adequate ventilation must be provided, such as when working in the confined spaces of tank interiors. Two-part coatings (e.g. two-component polyurethane coatings and two-component epoxy coatings) require mixing, sometimes with power equipment, of the components shortly before application, providing a "pot life" usually within hours for surface application of the coating mix. Some coatings may be applied to entire pieces of equipment, while other coatings may be used during "touch up" of small areas. An industrial facility may need to take certain equipment, part of the facility, or the entire facility, out of operation (such as during scheduled maintenance periods) to apply the coating. Equipment intended for "immersion service" may need to be emptied and made safe for the workers. Because of the extreme conditions in some industrial environments, multi-coat systems (primer coat with midcoats/topcoats) may provide the best coating performance.

Product Formulation:

The industrial maintenance coating system may include a primer and topcoat or primer, midcoat, and topcoat, or "high-build" (thick, dry) coating. Coating formulations may be water-based or solvent-based. Among the high performance coatings are the alkyd, polyurethane, epoxy, acrylic, silicone, inorganic zinc, and vinyl formulations. Newer technology is based on both one-component and two-component coatings that achieve lower VOC content while maintaining or enhancing the protection characteristics of the coatings (South Coast AQMD, May 14, 1999).

Traditional industrial maintenance coatings include the solvent-based alkyd formulations, with VOC contents ranging from about 300 g/l to 420 g/l. Newer high-solids alkyd formulations are available with somewhat lower VOC content (up to about 340 g/l) than traditional alkyd formulations. Past efforts to market water thinnable alkyd formulations with lower VOC contents showed low market acceptance (Gordon and McNeill, 1992). However, the development of water reducible alkyd formulations is still a possible option for achieving lower VOC content levels in the future.

Among newer technologies, one of the most important is the development of aliphatic polyurethane formulations. These include water-based, zero-VOC, two-component formulations that are intended to meet or exceed the industrial high-performance level of traditional solvent-based coatings. Other polyurethane formulations are available with low VOC contents (up to 100 g/l), much lower than traditional coatings. Besides water-based polyurethane, solvent-based polyurethane formulations are also available, but with higher VOC contents (up to about 350 g/l). Two-component polyurethane coatings must be prepared by mixing-in a curing agent prior to application. Besides two-component formulations, moisture-cured polyurethane formulations are available that rely on absorption of moisture from ambient air for curing. Polyurethane coatings provide exterior durability, chemical resistance, and high gloss.

Another important technology is the development of epoxy formulations. These coatings include water-based formulations with zero or low-VOC content (up to 100 g/l), and solvent-based formulations with higher VOC content (up to about 350 g/l). These are generally two-component coatings prepared by mixing-in a hardener prior to application. Epoxy coatings are used for their chemical resistance, such as to alkalies, soaps, detergents, oils, and solvents, as well as their resistance to hot and cold water, and for their adhesion to surfaces and materials. Because of these characteristics, epoxy coatings are often used as primers, linings for tanks and piping, and concrete surfacing. "High-build" epoxy coatings are available for lining tanks to protect them during immersion service. In some situations, epoxy coatings are not preferred for use as exterior topcoats, because they may chalk after exterior exposure (Gordon and McNeill, 1992).

Acrylic coating technology, in water-based and solvent-based formulations, is used for industrial maintenance because of the exterior durability and chemical inertness of the coatings. Many water-based acrylic formulations are available with low VOC contents. An acrylic coating may be recommended as a primer, topcoat, or as a single coat (sometimes referred to as "direct to metal" for steel). Some acrylic coatings, such as for single coat use, are recommended for light to moderate industrial environments. Certain acrylic coatings are suitable for use in food processing facilities regulated by the U. S. Department of Agriculture. Vinyl technology provides coatings with water, abrasion, and chemical resistance characteristics (Gordon and McNeill, 1992).

Zero and low VOC coatings may be formulated with novolac (phenol formaldehyde resin) technology or with siloxane technology. Siloxane is a class of silicon containing compounds. Siloxane technology may be used for providing greater heat-resistance characteristics to the coating.

There are modern coating systems available with zero-VOC content that combine a water-based epoxy primer and a water-based polyurethane topcoat. In this coating system, the best characteristics of epoxy and polyurethane coatings are used in a combination that is superior to either type of coating alone. Similar epoxy primer/polyurethane topcoat systems are available with low VOC contents. There are coating systems that combine an epoxy primer with an acrylic topcoat.

Coal tar epoxy coatings are used to protect steel and concrete in underground and immersion service and for protection against attack by acids, alkalies, petroleum, petrochemicals, sewage, and other chemicals. Some of these coatings are high solids formulations with low VOC content (up to about 250 g/l).

Zinc primers, containing zinc dust, are used for corrosion protection of iron and steel surfaces and structures in industrial situations. [A coating meeting the "metallic pigmented coating" definition would be subject to the proposed 500 g/l VOC limit for that category (see Section C-11)]. However, if a primer contains less than this level of metallic pigment, the coating would typically fall into the "industrial maintenance" category.] The function of zinc primers is to provide cathodic protection for underlying iron or steel, in situations where repainting is much more cost-effective than replacement of the iron or steel. Resins may be organic or inorganic (Gordon and McNeill, 1992). Inorganic zinc primers are available with zero and low VOC contents.

Proposed VOC Limit and Basis for Recommendation:

The proposed VOC limit is 250 g/l, except for certain climatic areas where the proposed VOC limit is 340 g/l, when justified. Both limits are to be, effective January 1, 2004. The proposed limits is are technologically and commercially feasible, by the effective date, based on our review of complying marketshare, currently available coatings, the Harlan Associates Study, the National Technical Systems (NTS) study, trade journals, and information from coatings and resin manufacturers, and field experience by the California Department of Transportation (Caltrans).

The VOC limit of 340 g/l would be allowed through a petition process and would be used only in the districts in the North Central Coast, San Francsico Bay Area, and North Coast Air Basins (see Section 3.8 of the proposed SCM). This separate VOC limit is provided because of past difficulties and limited opportunities to apply coatings complying with a 250 g/l VOC limit, for steel bridges in low-temperature, high-humidity, persistent fog areas along the California coast. The petition process would require a coating manufacturer, seller, or user to petition the Air Pollution Control Officer for the use of industrial maintenance coatings with VOC content up to 340 g/l, and to certify that coatings with VOC content below 250 g/l are not available for job requirements. A maximum allocation of VOC emissions due to excesses above 250 g/l would be available in each district by calendar year. The allocation would be provided by reserving a portion of the emission reduction, at 250 g/l VOC, that is not to be claimed for State Implementation Plan purposes.

The 1998 ARB survey shows that 28 percent of the market and 941 of the coating products already meet the proposed limit (Table VI-15). We estimate that emission reductions in the non-South Coast AQMD portion of the State will be 3 TPD from a 250 g/l limit.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

There are numerous coating formulations on the market, with zero or low-VOC contents that would comply with the proposed 250 g/l limit. Some are within the zero to 100 g/l range (South Coast AQMD, May 14, 1999; ARB list of coatings in Tables E-11 and E-12). Many of these are water-based polyurethane, epoxy, or acrylic formulations. There are solvent-based polyurethane, epoxy, and acrylic formulations with higher VOC contents in the 250-350 g/l range. We believe these coating formulations may be modified to comply with the proposed limit. For example, the resin may be modified to allow the solids content to be increased to displace some of the solvent. Current formulations with VOC contents above 350 g/l may need more extensive reformulation, such as solvent substitution with exempt compounds (e.g. Oxsol 100™ or the potential future exempt solvent tertiary-butlyl acetate (TBAc™)). For solvent-based two-component polyurethane formulations, it may be possible to lower the VOC content with new polyurethane prepolymers that need less solvent, and reformulating with reactive diluents (Dassner and Johnson, 1996). Reactive diluents initially act as solvents and then form part of the coating, instead of evaporating away, thus reducing VOC emissions.

The solvent-based alkyd formulations may contain VOCs in the range of 300 to 420 g/l. One possible compliance option for these coatings would be substitution of traditional organic solvents with low-reactivity exempt solvents. Oxsol 100™ is one exempt solvent currently available. A potential future exempt solvent is tertiary-butlyl acetate (TBAc™), believed to be a potential replacement for a variety of traditional organic solvents, such as toluene, xylene, methyl ethyl ketone (MEK), and methyl isobutyl ketone (MIBK) (Pourreau et. al., 1999). Two other options being considered are high-solids alkyd formulations and water reducible alkyds. Other options, going beyond pure alkyd formulations, involve the development of alkyd hybrids to achieve lower VOC levels while possibly enhancing other performance characteristics. Possible hybrids include rosin and phenolic-modified alkyds, acrylic alkyd copolymers, silicone alkyds, and epoxy ester modifications (Ryer, 1998).

The most common current district VOC limit is 420 g/l, although several districts have a VOC limit of 340 g/l. In the South Coast AQMD, the interim VOC limit is 250 g/l, effective July 1, 2002, and the final VOC limit is 100 g/l, effective July 1, 2006 (except for essential public service coatings and chemical storage tank coatings with different interim limits, as previously discussed).

The following summarizes VOC limits in the U.S. EPA regulation for industrial maintenance and related coatings.

Harlan Associates Study

The Harlan Associates Study tested the performance of 13 industrial maintenance primers (5 below 250 g/l, and 8 above), and 12 industrial maintenance topcoats (5 below 250 g/l, and 7 above). For the primers, the performance characteristics tested include stability, hardness, application, adhesion, drying time, impact resistance, flexibility, and salt spray. For the topcoats, the performance characteristics tested included the same tests and added tests for accelerated weathering and gloss.

In general, the performance of low-VOC coatings was similar to high-VOC coatings, however, some differences were noted. For the primers, the low-VOC primers showed better results from the tests for adhesion, flexibility, and impact resistance, while the high-VOC primers showed better results from the tests for salt spray, and water immersion. For the topcoats, the low-VOC topcoats showed better results from the tests for flexibility, while the high-VOC topcoats showed better results from the tests for appearance, salt spray, and gloss.

NTS Study

The National Technical Systems study tested the performance of industrial maintenance coatings individually as primer coats and topcoats, and together as coating systems (primer coats with appropriate topcoats). More than half of the 47 coatings tested were two-component coatings.

The study showed the performance of low-VOC coating systems was essentially similar to high-VOC coating systems except during one test. The low-VOC coating systems showed better mar resistance than the high-VOC coating systems. The study also showed that the performance of low-VOC primer coats and topcoats (tested separately) was essentially similar to that of high-VOC coatings.

Issues:

1. Issue: A limit of 250 g/l is not stringent enough, and an effective date of July 1, 2002, (previously proposed) is too late. Ultra-low VOC coatings and the raw materials to make them are already available. Currently available ultra-low VOC coatings outperform existing solvent-based coatings. The South Coast AQMD has identified 55 commercially available high-performance industrial maintenance coatings at 100 g/l or lower for essentially any use and application. The ARB should lower the VOC limit to 100 g/l, to be effective January 1, 2001.

Response: The industrial maintenance coatings category covers a very broad range of coating uses and coating formulations. The proposed VOC limit of 250 g/l and the proposed effective date (revised to January 1, 2004) would provide more opportunity for a broader variety of coating formulations to be available in the future to meet those varied needs. For example, the current alkyd formulations are solvent-based with VOC contents of about 400 g/l. We are aware of efforts to develop low-VOC alkyd formulations, including water-reducible alkyds. We believe that the proposal would allow resin and coating manufacturers to continue to develop different types of low-VOC coatings. This would ultimately provide more flexibility to industrial end-users to address specific coating needs.
2. Issue: The "industrial maintenance" category is too broad and does not consider special uses. Subcategories should be created and provided with less stringent limits when justified. Various commenters suggested the following subcategories.
· "Essential public services" (as in South Coast AQMD rule)
· Combining similar private facilities with "essential public services"
· "Chemical storage tank" (as in South Coast AQMD rule)
· Tank lining and piping
· Immersion service - water, wastewater, petrochemicals, other chemicals (general)
· Bridges and similar structures, storage tanks
· Zinc-rich coatings
· Include "new construction" in the definition of "industrial maintenance coatings"
· Include "commercial" and "institutional" use in definition of "industrial maintenance coatings"


More stringent limits and low-VOC technologies should be directed toward uses in which the technologies are most feasible. Less stringent limits should be provided for uses in which low-VOC technologies are less feasible.

Response: In general, dividing the "industrial maintenance" category into subcategories would make the SCM provisions more difficult for districts to enforce and create more confusion to the regulated community. As discussed above, there are several reformulation options available to meet the proposed limit. To provide time for essential public service agencies to complete their separate technology assessment and their administrative processes before low VOC coatings can be used, the ARB staff is proposing to delay the effective date of the 250 g/l limit until January 1, 2004. This extension would avoid the need to provide essential public services a higher VOC limit until they receive approval to use complying coatings.

As discussed above, we are proposing to allow up to 340 g/l coatings for all qualified users in districts with high humidity, persistent fog and cold temperatures.

3. Issue: Government agencies may specify or may need to approve coatings for certain types of use. There is a problem when no low VOC coating is specified/approved, because several years of field testing and evaluation by another organization may be needed before a low VOC coating can be used in some situations.
Response: The ARB staff is proposing to delay the effective date of the 250 g/l limit until January 1, 2004. This would provide time for essential public service agencies to complete their separate technology assessment and their administrative processes, required before low VOC coatings can be used. This extension would avoid the need to provide essential public services a higher VOC limit until they receive approval to use complying coatings. As discussed above, there are several complying solvent-based and water-based coatings reformulation options available. Existing coatings meeting the proposed 250 g/l limit are available now.
4. Issue: For immersion service, there are no accelerated test methods available. Many years of field testing are needed to demonstrate the suitability of a new coating for immersion service.

While in service, the coating may be submerged for years and may not be easily inspected visually. High-volume, turbulent liquid flow rates inside piping may substantially accelerate any coating failure and the subsequent equipment failure, if a defect starts in the coating. The coating must be highly reliable. The liability of coating failure is very high.

Essential public services, such as agencies that supply fresh water or treat wastewater, recommend a limit in the 340 to 350 g/l range to allow time for laboratory, field testing, and approval of low-VOC coatings. To address these concerns, South Coast AQMD has provided an interim district limit of 340 g/l for "essential public service coatings."

Response: See responses to issues 2 and 3.
5. Issue: Most bridges and similar structures have isolated areas that need higher-VOC coatings. Also, bridges exposed to the severe conditions along the California coast need higher-VOC coatings. These coatings have no suitable replacement. To address these concerns, the South Coast AQMD has provided an interim district limit of 340 g/l for "essential public service coatings."
Response: See responses to issues 2 and 3.


6. Issue: Development time for chemical tank coatings is very long. It is not possible to predict the types of aggressive chemicals that will need storage. For example, the composition of gasoline changes with respect to additives. To address these concerns, the South Coast AQMD has provided an interim district limit of 420 g/l for "chemical storage tank coatings" used for the interior of tanks storing oxygenated solvents, oxygenated solvent mixtures, or acid-based products.

Response: See responses to issues 2 and 3.
7. Issue: Some structures that were originally coated with solvent-based coatings need patch repair and maintenance with compatible coatings. A coating manufacturer or government agency may require specific high-VOC coatings for this purpose.
Response: See responses to issues 2 and 3. The time extension would apply to all uses, including patch and repair.
8. Issue: Consideration should be given to atmospheric conditions more extreme than in the South Coast AQMD during application of coatings. Other areas of California have higher temperatures, lower temperatures, and higher humidity. To accommodate these conditions, higher VOC coatings are needed. A limit of 340 g/l may be appropriate.
Response: See responses to issues 2 and 3.
9. Issue: A limit of 250 g/l is not proven for tank lining exposure or for aggressive exterior exposure involving ultra-violet light together with moisture, salt, chemical fumes, temperature extremes.
Response: See responses to issues 2 and 3. Coatings for lining tanks and for aggressive exterior exposure are available with VOC contents below 250 g/l, including several with zero VOC.
10. Issue: A limit of 250 g/l would prohibit the use of more than 95 percent of the coatings now used for oil refinery tanks. Similar problems exist with coatings for refinery vessels, exchangers, furnaces, and piping.
Response: See responses to issues 2 and 3.
11. Issue: A limit of 250 g/l is feasible with one important exception - coatings for tanks and piping.
 
Response See responses to issues 2 and 3.
12. Issue: The VOC limit should initially be 420 g/l, lowered to 340g/l after several years, and then lowered further to 250 g/l after several more years.
Response: See responses to issues 2 and 3.
13. Issue: To meet a limit of 250 g/l by 2002 (previously proposed effective date), regulatory flexibility should be provided for low volume, noncompliant, special-use coatings. Examples of regulatory provisions for flexibility include averaging, variance procedure, and/or small volume exemption.
Response: As discussed above, the ARB is proposing to include three of the small "national" categories in the SCM. These new categories include special-use small volume coatings for which it is not technologically and commercially feasible to meet the proposed 250 g/l limit. To provide flexibility for climatic conditions, the ARB is proposing a provision to allow a 340 g/l VOC limit for industrial maintenance coatings applied in persistent fog, low temperature regions in accordance with a petition process, as discussed above. To provide compliance flexibility, the ARB staff is considering development of an optional averaging provision for coatings manufacturers.
14. Issue: The ARB should withhold adoption of any SCM limit until results from the NTS study are reviewed by ARB and industry. The performance of reformulated industrial maintenance coatings is a major concern to painting contractors.
Response: As discussed above, the NTS study shows the performance of zero and low-VOC industrial maintenance coatings is similar to the performance of traditional high-VOC coatings. Results showed the mar resistance of low-VOC coating systems was better than high-VOC coating systems. The ARB staff is proposing to delay the effective date of the 250 g/l limit until January 1, 2004.
15. Issue: It is not possible to make industrial maintenance coatings of the quality, flexibility of application, and chemical safety expected by customers at the proposed VOC limit.
Response: See responses to issues 2 and 3. In addition, zero and low-VOC formulations result in lower VOC emissions and thus provide the safety benefits of lower solvent levels in the air.
16. Issue: There should be language uniformity with the national rule to minimize the marketing of two types of industrial maintenance coatings, one to California customers and another to the rest of the nation. Also, different definitions and different limits would prevent California customers from obtaining the best products.
Response: The national rule is intended to be minimum national requirements. Because California has the most severe ozone air quality problem in the nation, California needs to adopt lower VOC limits that are technologically and commercially feasible. The proposed SCM definition for industrial maintenance is similar to the national definition.
17. Issue: Water-based industrial maintenance primers will not adhere to concrete treated with form release compounds. Galvanized metal and aluminum and concrete treated with silicone, silane, or siloxanes do not allow water-based primers to stick. Solvent-based primers at 350 g/l are needed.
Response: See responses to issues 2 and 3. Proper surface preparation of the substrate is crucial to the performance of any coating, and especially so in the case of high-performance industrial maintenance coatings.


18. Issue: The definition of "industrial maintenance coating" should include coatings for electric transformers on a pole and underground vaults.

Response:The definition of "industrial maintenance coating" is sufficiently broad to include coatings for electric transformers on a pole and underground vaults. More specifically, section 2.25.1 refers to "…chronic exposure of interior surfaces to moisture condensation…", section 2.25.2 refers to "…chronic exposure to corrosive, caustic, or acidic agents…"; and section 2.25.5 refers to "… exterior exposure of metal structures and structural components…"
19. Issue: There is confusion concerning the use of "industrial maintenance coatings" and the use of "rust preventative coatings" because of category overlap, inconsistencies of the definitions, labeling requirements, and other inconsistent provisions.
Response: The ARB staff has revised the proposal to address these comments. The staff has deleted the provision that would have allowed "rust preventative coatings" that also meet the definition for "industrial maintenance coatings" to be subject only to the less stringent 400 g/l limit for "rust preventative coatings." Also, "rust preventative coatings" are for residential non-industrial use only and only on metal substrates. We are adding a definition for non-industrial use to clarify the distinction between industrial maintenance and rust preventative coatings.


20. Issue: There is a potential for manufacturers of industrial maintenance coatings to relabel higher VOC coatings into the "rust preventative coatings" category, to take advantage of a less stringent limit of 400 g/l. This could result in less emission reductions achieved in the "industrial maintenance coatings" category. The "rust preventative coatings" category is intended for residential users.

Response: The staff has deleted the provision that would have allowed "rust preventative coatings" that also meet the definition for "industrial maintenance coatings" to be subject only to the less stringent 400 g/l limit for "rust preventative coatings." This revision should more effectively separate the use of coatings in these two categories. ARB staff will monitor the sales of "rust preventative coatings" by evaluating data obtained from coatings manufacturers, to be submitted in accordance with Section 5.2 of the proposed SCM.
21. Issue: Anti-graffiti coatings are within the "industrial maintenance coatings" category. Since only industrial users may use coatings in this category, this creates a problem for residential, commercial, and institutional users of anti-graffiti coatings, who are not clearly industrial users. Certain high-performance coating characteristics are needed in anti-graffiti coatings, and hence they are similar to some types of industrial maintenance coatings.
Response: In addition to industrial use, the SCM allows the commercial and institutional use of anti-graffiti coatings that are classified as industrial maintenance coatings, for areas with extreme environmental conditions including surfaces subject to graffiti abuse/subsequent cleaning. For residential use (and for commercial, institutional, and industrial use as well), our review of anti-graffiti coatings (see Section B-1) shows there are numerous available coatings, including the permanent-type and the sacrificial-type, that can meet the proposed VOC limit of 100 g/l for flat coatings and the proposed VOC limit of 150 g/l for non-flat coatings. Permanent-type anti-graffiti coatings designed to resist repeated scrubbing with harsh solvents may be formulated and marketed by coatings manufacturers to be classified as either an industrial maintenance coating or as a flat/non-flat coating for general use, including residential use.

Industrial maintenance coatings are not limited to industrial applications. Residential, commercial, and institutional users can use anti-graffiti coatings subject to the 250 g/l industrial maintenance VOC limit. This is because industrial maintenance coatings can be used in commercial and institutional applications, and because we have removed the prohibition on the use of industrial maintenance coatings in residential applications.

15. Lacquer Coatings

Product Category Description:

Lacquers are clear or opaque wood coating products, including clear lacquer sanding sealers, formulated with cellulosic or synthetic resins to dry by evaporation without chemical reaction and to provide a solid, protective film. Lacquer sanding sealers are included in the category description and definition because they function like lacquers. Nitrocellulose and cellulose acetate butyrate are the most common film forming ingredients found in traditional lacquers.

Table VI-16 below summarizes our estimate of sales and VOC emissions from the lacquer coating category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

Lacquers are sold in California to major home centers, paint stores, lumber yards and hardware stores. The users range from the professional contractor to the homeowner or do-it-yourselfer. The many uses for lacquer include wood finishing for, but are not limited to, wood paneling, floors, doors, windows, furniture, and cabinets. In the last decade, wood products are increasingly supplied by the manufacturer pre-finished, eliminating the need to apply a finish at home or in the field. In California, a majority of new home or remodeling cabinetry is delivered pre-finished and field finished cabinetry occurs on a limited basis (e.g., custom fabrication).

Product Formulation:

The lacquer category is dominated by solvent-based formulations. Based on the 1998 ARB Architectural Coatings Survey solvent-based formulations accounted for 94 percent of the total sales volume with water-based formulations comprising the remaining six percent. In the 1998 ARB Architectural Coatings Survey this category is further broken down into clear and opaque lacquer categories. Clear lacquer formulations accounted for 69 percent of the total sales volume with opaque formulations accounting for the remaining 31 percent.

The VOC contents of traditional solvent-based lacquers are in the 650 g/l to 680 g/l range. The 1998 ARB Architectural Coatings Survey reports a VOC content range of 600 g/l to 680 g/l for solvent-based products, with a sales weighted average of 647 g/l. The formulations are clear coatings composed of synthetic thermoplastic film-forming materials in organic solvents (e.g., lacquer thinner or mineral spirit) that dry by solvent evaporation. Most lacquers are based on nitrocellulose, the film forming material, dissolved in lacquer thinner, the solvent. Nitrocellulose is a cotton-like material derived from mixing the cellulose from trees with nitric acid. These solvent-based formulations have the unique quality of being able to be re-wetted or dissolved when more lacquer or lacquer thinner is applied over existing, dry lacquer. The ability to rewet or re-dissolve lacquer allows for easy repair and recoating without the need to completely remove the existing finish.

For the water-based formulations, the 1998 ARB Architectural Coatings Survey reports a VOC content range of 160 g/l to 220 g/l with a sales weighted average of 181 g/l. Water-based formulations are similar to solvent-based formulations in creating a thermoplastic film, but with the use of vinyl, acrylic, polyurethane or urethane/acrylic latex blend type resins that are not resoluble in their original solvent.

Proposed VOC Limit and Basis for Recommendation:

The proposed 550 g/l limit for lacquers is technologically and commercially feasible by January 1, 2003, based on information from coating manufacturers and complying marketshare. The use of acetone as an alternative VOC exempt solvent has resulted in achieving 550 g/l VOC contents without sacrificing significant properties preferred by the wood finishing industry. Major manufacturers have introduced nitrocellulose lacquers using acetone to lower the VOC content to 550 g/l. Other alternative solvents for lacquer may include t-butyl-acetate (VOC exemption pending) and Oxsol 100 (parachlorobenzotrifluoride - VOC exempt).

The South Coast AQMD Rule 1136 "Wood Products Coatings" was amended in June 1996 to include a 550 g/l VOC limit for these coatings. At that time, the coating formulators supported the South Coast AQMD 550 g/l limit for lacquers. Surface Protection, Inc., Guardsman, Akzo-Nobel, Sherwin Williams, and AMT have all introduced acetone-based formulations of nitrocellulose lacquers, which have been used successfully by manufacturers of wood furniture, kitchen and bath cabinets, and shutters. (South Coast AQMD, 1996)

Alternative formulations of lacquers have seen significant development in recent years. The water-based formulations reported in the 1998 ARB Architectural Coatings Survey also provide formulators an avenue of compliance. The proposed VOC limit provides manufacturers the flexibility to continue the use of traditional lacquers or take advantage of existing water-based formulations. The emission reductions below have been adjusted to exclude the Clear Brushing Lacquer category.

Table VI-17 summarizes our estimate of complying products, marketshare, and emission reductions outside the South Coast AQMD.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

 
Issues
1. Issue: The use of acetone could result in flammability problems.
Response: Many of the solvents used in solvent-based lacquers or other coatings are also flammable and must be handled with care. Acetone's flashpoint temperature, flammability classification and lower explosive limit are similar to other solvents (e.g., MEK, toluene, xylene) found in solvent-based coatings. Flammability classifications by the Fire Department are the same for acetone, MEK, toluene, and xylene. Using operating guidelines for working with flammable coatings under well-ventilated areas, as prescribed by fire department codes, will avoid the concentration of acetone vapors required to cause an explosion. (South Coast AQMD, 1996)

16. Low Solids Coatings

Product Category Description:

Low solids coatings are products formulated to contain one pound (0.12 kilogram) of solids or less per gallon of coating. The VOC content of the low solids coating is calculated as the actual VOC of the material, that is, without subtracting out the water and exempt compounds. This category was not included in the 1989 SCM, although it is in some more recently amended district rules. The only low solids coatings reported in the 1998 ARB survey are low solids stains and low solids wood preservatives.

The National Rule has separate categories for low solids stains and low solids wood preservatives, both with VOC limits of 120 g/l. The U.S. EPA's rationale was that a low solids category was needed because at a very low solids content, coating coverage is controlled by volume, not the solids content. In other low solids applications, such as lacquers for metal, the solids content, rather than the volume, determines the amount of coating used; that is, more gallons of a low solids coating would be needed for the same coverage as a higher solids coating. Thus, the U.S. EPA restricted the low solids category to stains and wood preservatives because it had no data or other information about any other low solids categories (U.S. EPA, 1998).

Tables VI-18a and VI-18b below summarize our estimate of sales and VOC emissions from the low solids coating category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.
PD = Protected data.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.
PD = Protected data.

It should be noted that the definition used in the ARB's 1998 Architectural Coatings Survey was that of the draft National Rule, which included a 50 percent water requirement.

Product Use and Marketing:

Low solids coatings are sold in hardware stores and home centers. The products are used for the same purposes as regular stains and wood preservatives, for example, protection of exterior wood surfaces.

Product Formulation:

Low solids stains and wood preservatives are formulated to contain less than one pound of solids per gallon of coating. This category includes high water, low solids coatings that could meet the 120 g/l VOC limit by formulating with water or exempt solvents.

The calculation of VOC on a material basis is an important criterion in this category. For example, in a typical low solids product, on a less water and exempt solvents basis, the labeled VOC would be 470 g/l, but only 80 g/l on a material basis. Because the low solids products are mostly water, we believe this calculation is a reasonable approach for determining the VOC content.

Proposed VOC Limit and Basis for Recommendation:

The proposed 120 g/l VOC limit is technologically and commercially feasible by the January 1, 2003, effective date based on: complying marketshare; the limit in current district rules and the National Rule; and discussions with manufacturers and other interested parties.

e recommend that the low solids stains and low solids wood preservatives be combined into one low solids category because both subcategories have the same VOC limit. This is a cap on current VOC contents.

The tables below also show that VOC emission reductions in the non-South Coast AQMD portion of California would be virtually zero from implementing the proposed limit of 120 g/l for low solids coatings.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
PD = Protected Data.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
PD = Protected Data.

Issues:

1. Issue: In the definition for low solids coating, at least half of the volatile component is water. It is unclear whether this requirement is by weight or by volume.

Response: In an earlier version of the proposed SCM, we had included the language from the National Rule requiring that at least half of the volatile component be water. We have dropped that requirement to allow for the use of either exempt solvents or water in the formulation of low solids products.


2. Issue: Industry needs limits for low-solids stains and preservatives, as well as low-solids waterproofing sealers and general sealers.

Response: The suggested low solids products are included in the category. We have named the category "low solids coatings" to allow formulation of other types of low solids products such as these coatings.


3. Issue: The low-solids definition in the National Rule doesn't specify whether the half of the volatile component is water by weight or volume; we assume it's by volume. The definition should say "water or exempt compounds." This definition is considerably at variance with the definition in Rule 1113 and the National Rule.

Response: The commenter refers to a previous version of the SCM in which we used the National Rule definition that included the 50 percent water requirement and did not allow the use of exempt compounds. This definition was different from the South Coast AQMD definition in Rule 1113. The proposed definition is now identical to the definition in several district rules and does not exclude the use of exempt solvents.


4. Issue: The definition for low solids coatings should include earlier proposed language limiting low-solids coatings to those with water comprising half of the volatile component, unless this is considered redundant.

Response: The proposed definition matches the definition in several existing district rules. Under the proposed definition, low solids coatings must include a large percentage of water or exempt solvents to qualify for inclusion in the category.

17. Multi-Color Coatings

Product Category Description:

Multi-color coatings are coatings packaged in a single container that, when applied in one layer, exhibit more than one color. They are designed for use as a substitute for wallpaper in offices, hotels, hospitals, and other public buildings. The individual colored pigment flecks are suspended in a base of a contrasting color, and when sprayed on a surface, produce a speckled, textured surface. These coatings are durable enough to withstand repeated washings (South Coast AQMD, 1996; LeSota, 1995; Coronado Paint, undated).

Table VI-20 below summarizes our estimate of sales and VOC emissions from the multi-color coatings category.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).
** Grams VOC per liter of coating, less water and exempt compounds.
*** Includes 100 percent solid coatings.
PD = Protected Data.

Product Use and Marketing:

Multi-color coatings are not a do-it-yourself item, and are sold by distributors or direct from the manufacturer to the end user. These products are a specialty item applied by professional contractors who specialize in applying multi-color coatings.

Multi-color coatings are spray applied, but the manufacturer's recommendation must be followed on the type of spray system that should be used. Stirring should also follow the manufacturer's directions to avoid disrupting the suspended contrasting color particles. Also, color uniformity batch-to-batch may be more challenging with these coatings than with other coatings. It is possible for the applicator to achieve an individual stylized effect by using different background shadings, blending different colors, or using different application techniques. Multi-color coatings can be used on drywall, wood, masonry, steel, galvanized metal, aluminum, and wallpaper, provided the proper surface preparation and primers are used. Touch-up also must be done following the manufacturer's recommendations. A clear coat can be applied on top of the multi-color coating to give a glossy surface or a slight shine, and to improve scrubbability and abrasion resistance (Coronado Paint, undated).

Product Formulation:

There are a number of high-VOC solvent-based coatings, as well as several complying water-based formulations reported in the 1998 ARB Architectural Coatings Survey.

The South Coast AQMD performed a technology assessment of these coatings during development of its 1996 amendments to Rule 1113. Water-based formulations using a modified acrylic resin system have the same properties as the older solvent-based alkyd or lacquer resin technology. Manufacturers reported some difficulty with reformulating metallic multi-color coatings, but were able to reformulate prior to January 1998, the effective date of the South Coast AQMD's 250 g/l VOC limit (South Coast AQMD, 1996).

The ARB concurs with the South Coast AQMD's conclusions based on its own investigation. ARB staff contacted three manufacturers of multi-color coatings. Two of the manufacturers are currently selling water-based products that are acceptable substitutes for their solvent-based formulations. The VOC contents are at or below 250 g/l. The third manufacturer is in the final stages of development of a water-based, complying product that will be available for the January 1, 2003, compliance date of the SCM.

Proposed VOC Limit and Basis for Recommendation:

The proposed 250 g/l VOC limit is technologically and commercially feasible by the January 1, 2003, effective date based on: complying marketshare; discussions with manufacturers who have or will soon have complying products; the limit in effect in the South Coast and Antelope Valley districts; and the technology assessment performed by the South Coast AQMD in 1996.

Lower-VOC water-based technology is available and has been commercially accepted as a viable alternative to the higher-VOC, solvent-based multi-color coatings. Reformulation efforts to achieve compliance with the proposed limit will continue to focus on replacing solvent-based formulations with water-based products. One manufacturer noted that many contractors prefer water-based multi-color coatings because they are less hazardous to apply, and they can be used in healthcare facilities where solvent odor must be minimized.

The table below also shows that VOC emission reductions in the non-South Coast AQMD portion of California would be approximately zero tons per day, on an annual average basis, from implementing the proposed limit of 250 g/l.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

Issues:

1. Issue: "Applied in a single coat" is not clear in the category definition. That might mean that someone couldn't put a second coat on. Should change to "that exhibits more than one color when applied in a single coat."

Response: We have changed the wording of the definition to clarify that the coating exhibits more than one color when applied in a single coat.

18. Primer, Sealer, and Undercoater Coatings

Product Category Description:

The primer, sealer, and undercoater category is a generic term used to describe coatings, typically the initial coat, used to provide a smooth surface for subsequent coats. Primers, sealers and undercoaters are also used to provide a shield between the substrate and the subsequent coat or to provide adhesion for the topcoat. (South Coast AQMD 1999).

This category excludes specialty primers, which are those products formulated to block stains, or for application to substrates damaged by fire, smoke, or water, or to condition excessively chalky surfaces. This category also excludes primer, sealer and undercoater products that are dry to the touch in 30 minutes and can be recoated in two hours. These products fall under the category of quick-dry primer, sealer, and undercoater coatings.

The National Rule has one category for primers and undercoaters, and another category for sealers. (U.S. EPA, 1998) Because of the trend toward multi-functional products that are primers, sealers, and undercoaters, we have grouped these products, with the exceptions noted above, into one category. This is also how most district rules treat these coatings.

Table VI-22 below summarizes our estimate of sales and VOC emissions from the primer, sealer, and undercoater coatings category. These numbers are a compilation of two product categories surveyed in the 1998 ARB Architectural Coatings Survey- Primers, Sealers, and Undercoaters; and Sealers (ARB, 1999).

In 1996, nearly 900 products were sold in California by 81 companies, accounting for over 6 million gallons of product per year. Approximately 55 percent of the sales are water-based products, and 45 percent of the sales are solvent-based products. The sales weighted average (SWA) VOC content for all products in this category is 169 g/l; water-based products have a SWA VOC content of 105 g/l, and solvent-based products have a SWA VOC content of 360 g/l. The VOC emissions for water-based products, excluding those emissions occurring in the South Coast AQMD, are 1.2 tons per day (TPD), and the VOC emissions for solvent-based products is 3.4 TPD, yielding non-South Coast AQMD VOC emissions of 4.6 TPD for the category.

Please note that the specialty primer category was not surveyed as a separate category, and some of the products reported in the primer, sealer, undercoater category are actually specialty primers.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

Primers, sealers, or undercoaters are particularly useful when coating new wood or other surfaces that have not been previously coated, when recoating a surface that is uneven or badly deteriorated, and when coating a surface that has been stripped or is worn down to the original surface. (PQI,a) The use of these products will reduce the incidence of cracking and flaking, which may occur when coating is applied directly to the substrate. (PQI, b)

Traditionally, there have been specific coatings for a variety of uses, including priming, sealing, stain blocking, and hiding. Furthermore, specific coatings were formulated for different substrates, including wallboard, plaster, concrete, masonry block, pipe insulation, and coated glossy and non-glossy surfaces. However, the recent trend has been to develop multi-functional primers that can be used for a variety of substrates. (South Coast AQMD 1999)

Primers, sealers and undercoaters are applied to a wide variety of substrates, including, but not limited to, brick, ceramic tile, cinder block, concrete, cured plaster, Masonite®, metal, fiberglass, Formica®, glass, vinyl siding, stucco, wallcoverings, as well as previously coated surfaces.

Primers, sealers and undercoaters can be purchased by all consumers at outlets such as hardware stores, home supply stores, and retail paint stores, and by professionals at wholesale only outlets.

Surface preparation is the most important step in any coating application because it directly affects the durability and appearance of the completed job. Coatings manufacturers develop surface preparation recommendations for their products and provide these recommendations to the consumer by printing them in their literature and product labels. Most companies consider these methods to be minimum requirements for a satisfactory job, and by following these recommendations the consumer is assured a satisfactory job under most conditions. (McNeill)

General surface preparation calls for all surfaces to be clean and dry. All dirt, dust, rust, stains, scale, mildew, wax, grease, oil, bond-breakers, efflorescence, and other contaminants that can adversely affect the coating adhesion and performance should be removed, as should all loose, peeling, or checked paint. Glossy surfaces should be deglossed. (Dunn-Edwards)

Product data sheet review indicates that the minimum recommended application temperature (air, surface, and product) for primers, sealers, and undercoaters ranges from 40o F to 50o F, depending upon the formulation. Problems such as "ghosting", "mud cracking", and other film irregularities can occur if the proper product is not chosen for the range of application. (Bennette, a) A review of product data sheets for primer, sealer, and undercoater products indicated that most latex products recommend a minimum application temperature of 50oF, and most alkyd products recommend a minimum application temperature of 40oF.

Manufacturer's recommendations for maximum application temperature must also be adhered to, as painting in hot weather can also result in less than satisfactory results. While most manufacturers do not indicate a recommended maximum application temperature, some specify maximum application temperatures as high as 120oF, while others specify maximum application temperatures as low as 85oF. Temperatures exceeding 90oF will often cause a coating to dry too fast, and "dry rolling" will be accentuated at higher temperatures, and painting in direct sunlight at temperatures above 90oF may cause surface wrinkling. (Bennette, b) Primers, sealers, and undercoaters may be applied by brush, coating pad, roller, airless sprayer, high-volume low-pressure sprayer, or electrostatic sprayer.

Depending on the porosity of the substrate, coverage per gallon typically ranges from 250 to 450 square feet. In addition to the porosity of the substrate, coverage is also influenced by the amount of solids and hiding pigment in the coating. (Dunn-Edwards) These products are to be stirred thoroughly prior to use, and stirred occasionally during use. The product should be applied liberally and spread evenly and quickly, working from wet area to dry area to avoid lapping, and allowed to dry for the recommended time prior to recoating.

In addition to a minimum recoat or topcoat time, some manufacturers recommend a maximum recoat time for primers, sealers, and undercoaters. After they are applied, these products can begin to weather and harden. If not topcoated within a reasonable time, they can become too hard or weathered to allow the topcoats to penetrate and adhere, and peeling may result. This situation occurs mostly with oil based or other solvent-based primers; affected products will have a statement on the product label and information sheet stating the recoat "time window." Water-based acrylic primers will generally not become too hard to allow for proper adhesion of the topcoats, however, if they are not topcoated within a reasonable time, they can begin to weather, which can cause adhesion problems. (Dunn-Edwards)

Product Formulation:

This category includes a variety of available coating technologies in its formulations; alkyds, modified alkyds, oleoresins, epoxies, specialty resins, and emulsions are just a few of the formulations used. (South Coast AQMD 1999).

Coatings ingredients fall into four basic categories:
· Pigments to provide color and hide;
· Binder to hold the pigment particles together and provide adhesion;
· Liquid to act as a carrier for the pigments and binder; and
· Additives to enhance certain properties like brushing ease and mildew resistance (PQI,c).

As indicated previously, over half of the products reported in the 1998 ARB survey are water-based, that is, water is the liquid that acts as the carrier for the pigments and binder. The binder consists of a dispersion of fine particles of synthetic resin, and so the products are also referred to as latex coatings. Latex binders may be acrylic, vinyl chloride, vinyl acetate, styrene, or a combination of these materials in a single resin. (PQI,c) The largest contributors of VOCs in latex coatings are glycols, whose main purpose is to provide freeze/thaw resistance, and coalescence.

In alkyd and oil-based coatings, most of the liquid is a solvent, usually a petroleum distillate. The solvent-based coatings in this category are commonly formulated using alkyd resins as binders.

Proposed VOC Limit and Basis for Recommendation:

The proposed VOC limit for the primer, sealer, undercoater category is 200 g/l. The proposed VOC limit is technologically and commercially feasible by the January 1, 2003, effective date based on our review of product data sheets, analysis of complying marketshare, information provided by manufacturers, and laboratory performance tests as described below. Our recommended limit is consistent with the interim limit adopted by the South Coast AQMD in Rule 1113.

Industrial maintenance coatings recommended for use as primers, sealers, or undercoaters are subject to the proposed VOC content limit for industrial maintenance coatings (250 g/l). The National Rule VOC limit for primers and undercoaters is 350 g/l, and the VOC limit for sealers is 400 g/l.

The 1998 ARB survey, the national survey, and the South Coast AQMD staff survey of product data sheets all indicate that compliant primers, sealers, and undercoaters are commercially available and command a large marketshare.

Data reported in the 1998 ARB survey indicate that 73 percent of the products sold in California already comply with the proposed VOC limit of 200 g/l. We estimate emission reductions of 0.77 0.64 TPD VOC from the proposed limit for the areas outside of the South Coast AQMD.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

To meet the proposed VOC limit, manufacturers can employ water-based technology, and achieve further reductions in water-based technology through the use of lower VOC coalescing solvents and freeze/thaw resistance additives.

The Sherwin-Williams Company, in their 1998-1999 Painting & Coating Systems catalog for Specifiers and Applicators, includes numerous primers, sealers, and undercoaters that comply with the proposed limit. A few of these are discussed below.

Sherwin-Williams' Loxon Exterior Acrylic Masonry Primer (A24 Series) is recommended for masonry, cement, and stucco, and has a VOC of only 60 g/l. The product data sheet indicates that this primer passes moisture resistance, wind-driven rain, moisture vapor permeability, flexibility, tensile strength, alkali resistance, and mildew resistance tests. (South Coast AQMD, 1999)

Sherwin-Williams' PrepRite 200 and 400 Interior Latex Primer are considered their professional best line, and good quality, professional line, respectively. Both of these products have VOC contents that are below the proposed limit. The product data sheets indicate that these products prime and seal, have excellent holdout, and accept latex, alkyd, and waterborne epoxy topcoats. Their PrepRite Classic Interior Latex Primer, also with a VOC content below the proposed limit, is indicated as "our finest quality primer and sealer, designed for use on interior wood, drywall and masonry/concrete surfaces, providing excellent enamel hold out for any recommended topcoat and excellent sanding characteristics." It is recommended as a high quality wall primer or enamel undercoater. Their PrepRite ProBlock Latex Primer/Sealer has the same low VOC content, is recommended for both interior and exterior uses, has excellent adhesion to hard, slick, or glossy surfaces, and can be topcoated with a latex or alkyd topcoat. Their catalog includes several, additional primers for both interior and exterior uses. The VOC content information provided above is for white coatings only. (South Coast AQMD, 1999)

Insl-X, Zinsser, and Zehrung have developed and marketed zero- and low-VOC primers, sealers, and undercoaters recommended for a variety of uses. (South Coast AQMD, 1999)

Harlan Study

In 1995, Harlan Associates tested 20 different primers/sealers. In this test, only two of the twenty coatings tested qualify as "quick-dry primers" as defined by several district rules. According to these tests, most of the low VOC primers had performance characteristics similar to the high-VOC primers. The following tests showed relatively equivalent results including:

· Stability
· Application
· Adhesion
· Appearance
· Dry-to-Touch Time
· Flexibility
· Grain Raising
· Sag Resistance
· Alkali Resistance


Two differences were noted between the low-VOC and high-VOC primer/sealers; freeze-thaw resistance and dry-to-recoat times. The freeze-thaw resistance test is used to determine the resistance of a coating to storage in very cold temperatures and only affects water-based coatings. Nine out of twelve low-VOC coatings passed this test. Also, ten of the twelve low-VOC coatings tested had acceptable dry-to-recoat times of 6 hours or less. (ARB, 1995; Cowen, 1999)

NTS Study

ARB staff's analysis of the National Technical Systems (NTS) data from the South Coast AQMD's "Phase II Assessment Study of Architectural Coatings" indicates that overall, low-VOC primer, sealer, and undercoater coatings exhibited similar performance to high-VOC primer, sealer, undercoater coatings. This study evaluated the performance characteristics of primers, sealers, and undercoaters for a variety of characteristics, including brushing properties, dry times, leveling, sag resistance, hiding, and film thickness. (NTS, 1999)

Issues:

1. Issue: As currently written, the primers category would include those made from bituminous resins. Bituminous primers should be separately defined or should be included in the bituminous coatings category at the federal level.

Response: Bituminous roof coatings are defined as a coating labeled and formulated for roofing that incorporates bitumens. Bituminous primers would be included in that coatings category. Please refer to the section on bituminous roof coatings for further information.


2. Issue: The primer, sealer, and undercoater category should be divided/categorized into the following: interior primers and undercoaters; exterior primers and undercoaters; interior sealers; and exterior sealers.

Response: As indicated by product labels and product data sheets, many of the products in the primer, sealer, undercoater category are intended for use on interior and exterior surfaces. The 1998 ARB survey indicates that 41 percent of the products reported in this category are for interior use, 31 percent are for exterior use, and 28 percent can be used on either interior or exterior surfaces. For the sealer category, which was surveyed separately, the survey indicates that 61 percent of the products are for interior use, 26 percent are for exterior use, and 14 percent can be used on either interior or exterior surfaces. Further, the trend toward multi-use products has resulted in products for which there is no clear-cut distinction between products that seal and products that prime or undercoat. Subcategorization of the primer, sealer, undercoater category into exterior and interior and sealer vs. primer or undercoater would create artificial categories for which very few products exist.


3. Issue: A specialty primer category with a VOC content of 350 g/l should be established. We sell three specialty primers that are used to prime poured-in-place concrete and tilt-up concrete. The product is designed to go through form oils and release agent materials that are used in the forming of the concrete and remain on the surface of the concrete. Lower VOC products (including latex systems) cannot penetrate these materials and provide the required adhesion.

Response: Concrete should be allowed to cure for 30 to 60 days before coating, and the moisture content should be no higher than 15 percent to ensure success. Moisture is a common cause of coatings failing to properly adhere on concrete. If moisture can penetrate cured concrete it will leach out alkaline salts that can react with the resin in many coatings causing early adhesion failure. A test for moisture migration should be conducted if a moisture condition is suspected.

Release compound is formulated to weather off within a relatively short time, and should decompose by the time the concrete has cured to the correct moisture content. It is only necessary to brush off the decomposed release compound before coating. Release compound not decomposed by weathering must be removed before coating for proper adhesion. Water or abrasive blasting will effectively remove release compound.

A review of product data sheets indicates there are products for the specific applications indicated by the commenter that comply with the proposed standard. For all but one product, use instructions direct the applicator to allow the concrete to fully cure, as specified above.


4. Issue: We have two specialty solvent-based primers designed to go over less than ideal wood surfaces and chalky coating. The higher VOC (350 g/l) solvent primers penetrate the chalky surfaces and provide excellent adhesion for subsequent topcoats. Other surface types requiring specialty primers with VOC levels of 350 g/l are galvanized metal, aluminum, copper, stainless steel, ferrous metal, and baked enamels.

Response: We are proposing a specialty primer category with a VOC limit of 350g/l to address these issues.


5. Issue: We feel the categories of quick dry primers, sealers and undercoaters should be reinstated.

Response: The Quick-dry primer, sealer, and undercoater category exists in this proposed SCM. However, it should be noted that the proposed VOC limit for the quick-dry primer, sealer, undercoater category is the same as the proposed VOC limit for the primer, sealer, undercoater category. Please refer to the section on quick-dry primers, sealers, and undercoaters for further information.
 
 
6. Issue: In the South Coast AQMD rule, they provided a higher VOC limit for specialty primers applied to chalky substrates. We propose a stain blocking primer, or including stain blocking in the specialty primer definition. Woods have tannins that bleed through water-based products.
Response: We have created a specialty primer category with a VOC limit of 350 g/l for primers applied to block tannins and other stains, and to condition excessively chalky surfaces. Please refer to the section on specialty primers for further information.


7. Issue: The definition for sealers precludes sealers which are used to seal a substrate to protect it from penetration of foreign matter but which are not topcoated. This needs to be corrected.

Response: We do not agree. Primers, sealers, and undercoaters in district rules have always been defined as a primary coat which is topcoated. Primers, sealers, and undercoaters are grouped together for this reason. We are proposing 250 g/l VOC limits for sealers designed as topcoats, such as waterproofing sealers for wood or concrete. Please refer to the waterproofer sealers category descriptions.

19. Quick-Dry Enamel Coatings

Product Category Description:

Quick-dry enamel coatings are high gloss coatings designed to dry quickly. They are used on interior and exterior surfaces of residential and commercial buildings. Quick-dry enamels are a subset of high gloss non-flat coatings, but have historically been treated as a separate category in district architectural coatings rules. In order for a non-flat coating to be classified as a quick-dry enamel, it must be dry to touch within two hours after application, be tack-free within four hours, and dry hard within eight hours. It must also have a gloss of 70 or above on a 60^o meter.

Table VI-24 below summarizes our estimate of sales and VOC emissions from the quick-dry enamel coatings category based on the 1998 ARB Architectural Coatings Survey results. This category is the seventh largest coatings category with regard to VOC emissions and the fifteenth largest category with regard to sales volume. The VOC emissions from quick-dry enamels represent about 4 percent of the total emissions from architectural coatings (ARB, 1999). VOC emissions in California, excluding the South Coast AQMD, are approximately 2.2 tons per day. As shown below, all of the emissions from this category are from solvent-based products.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

** Grams VOC per liter of coating, less water and exempt compounds.

Product Use and Marketing:

As with other non-flat coatings, quick-dry enamels can be brushed, rolled, or sprayed on the surface to be coated. "Do-it-yourselfers" and paint contractors can purchase coatings that meet the quick-dry enamel criteria at outlets including hardware stores, home supply stores, and retail paint stores. Quick-dry enamels are typically used where the coated surface needs to dry quickly to minimize dust contamination (e.g., new home construction) or the area needs to be returned to service quickly (e.g., restaurants) (South Coast AQMD, 1999). As with other non-flat coatings, quick-dry enamels may be used on surfaces where frequent cleaning is necessary and in rooms where moisture is present. Kitchens, bathrooms, hallways, children's rooms, doors, window frames, shutters, and wood trim may be coated with such coatings. Commercial buildings and institutions may use quick-dry enamel coatings on surfaces such as walls, corridors, and stairwells. With proper surface preparation and priming (if necessary), quick-dry enamels can be used on a large variety of interior and exterior substrates including drywall, plaster, masonry, wood, and metal.

The 1998 ARB survey showed that about 22 percent of the quick-dry enamels sold in 1996 were formulated for interior applications, 4 percent for exterior applications, and 74 percent were formulated for both interior and exterior applications (ARB, 1999).

Product Formulation:

As previously mentioned, all of the coatings reported under the quick-dry enamel category in the 1998 ARB survey were solvent-based. Quick-dry enamels are typically formulated using alkyd resins as binders. The amount of quick-dry enamels sold has increased approximately 87 percent since the 1993 ARB survey of architectural coatings (which reflected 1990 sales). Past ARB surveys show a large fluctuation in the volume of quick-dry enamel coatings sold (ARB, 1991; ARB, 1986). The overall sales-weighted average VOC level for quick-dry enamels has remained the same since 1990, and all of the products reported in this category have remained solvent-based (ARB, 1999).

Product information sheets published by coatings manufacturers indicate that there are a number of lower-VOC, water-based latex coatings available that meet the gloss and dry time criteria of quick-dry enamels, although those products may not be labeled as quick-dry enamels. Those products are discussed in more detail below.

Proposed VOC Limit and Basis for Recommendation:

We recommend a 250 g/l VOC limit for quick-dry enamel coatings, effective January 1, 2003. The proposed VOC limit is technologically and commercially feasible by January 1, 2003, based on our review of ARB survey data on marketshares, product information from manufacturers, and laboratory performance tests. The proposed VOC limit is lower than the 450 g/l national limit recently promulgated by the U.S. EPA (U.S. EPA, 1998). The most common limit for quick-dry enamels currently in effect for those California air pollution control districts that have architectural coatings rules is 400 g/l. Since September 1990, the Santa Barbara County Air Pollution Control District has included a 250 g/l limit for quick-dry enamels in its architectural coatings rule. In 1999, the South Coast AQMD adopted a 250 g/l limit for quick-dry enamels that will become effective July 1, 2002, and also adopted a 50 g/l limit that will become effective July 1, 2006. Our recommended limit is consistent with the interim limit adopted by the South Coast AQMD.

As discussed in the non-flat coatings category description, we are recommending the same 250 g/l VOC limit for the quick-dry enamel category as for the high gloss subcategory of non-flat coatings. Our recommendation is primarily based on enforcement concerns, especially for California districts with fewer enforcement resources than the South Coast AQMD. Many high gloss non-flat coatings satisfy the gloss and dry time criteria of quick-dry enamels, and there is overlap between the high gloss non-flat and quick-dry enamel categories. Companies could relabel products rather than reformulate them if the VOC limit is different for those two categories. Moreover, some high gloss products might be illegally labeled as quick-dry enamels even if they do not meet the dry time criteria, which would be problematic for enforcement personnel in some districts to detect. Thus, for greater enforceability, the proposed SCM includes a subcategory for high gloss non-flat coatings that has the same VOC limit as the quick-dry enamel category.

Since most districts' architectural coatings rules currently include a quick-dry enamel category, the proposed SCM retains that category with its new VOC limit. This was done so that district rules, once amended in accordance with the proposed SCM, will clearly show that the VOC limit for quick-dry enamels is reduced from 400 g/l to 250 g/l. Further, we recommend that districts eventually eliminate the quick-dry enamel category from their architectural coatings rules, which would in effect require such products to meet the VOC limit of the high gloss
non-flat subcategory.

Table VI-25 does not present specific data regarding the marketshare of products that comply with the proposed limit due to confidentiality concerns (ARB, 1999). It is important to point out that manufacturers in the past have typically marketed only solvent-based alkyd coatings as quick-dry enamels. However, as discussed below, a number of water-based latex coatings that comply with the proposed limit meet the gloss and dry-time requirements of this category. We expect that, in order to meet the proposed limit, most solvent-based alkyd products would be reformulated as water-based latex products. More information on the formulation of water-based latex products can be found in the low and medium gloss non-flat category description. Coating manufacturers may also choose to reformulate solvent-based alkyd products using existing low-VOC alkyd technology (e.g.,Vianova Resins, 1999).

The table below shows that VOC emission reductions in the non-South Coast AQMD portion of California would be approximately one ton per day, on an annual average basis, from implementing the proposed limit of 250 g/l.

* Based on ARB's 1998 Architectural Coatings Survey Results Final Report (ARB, 1999).

 
NTS Study

Independent laboratory performance tests of a number of coatings were recently conducted by National Technical Systems (NTS) under contract with the South Coast AQMD. Included in those tests were eight coatings with VOC levels at or below 250 g/l (range: 0 to 250 g/l) that meet the gloss and dry time criteria of quick-dry enamels. NTS also tested 5 coatings that were labeled as quick-dry enamels that had VOC levels of 400 g/l. Although three of the five 400 g/l coatings did not appear to meet the gloss criterion, they will be included in this comparison. For this discussion, those coatings that comply with the proposed 250 g/l limit ("low-VOC coatings") are compared with the 400 g/l coatings ("high-VOC coatings"). Similar performance for low-VOC and high-VOC coatings was seen in tests of brushing properties and film thickness. The high-VOC coatings had somewhat better leveling performance, but the
low-VOC coatings performed better with regard to sag resistance. Block resistance tests for the interior coatings showed that some of the best-performing coatings were in the low-VOC category. Block resistance for exterior coatings was somewhat better for high-VOC coatings. Low and high-VOC interior coatings had similar results in tests for dirt removal ability. High-VOC interior coatings generally showed better scrub abrasion resistance, although one low-VOC coating had the best performance in this test (NTS, 1999).

Harlan Study

In 1995, Harlan Associates, Inc., under contract with ARB, conducted performance tests on 10 interior and 10 exterior non-flat coatings. Those coatings were selected in 1994 from commercially available coatings. The VOC levels of the twenty coatings ranged from 15 g/l to 459 g/l. Inspection of the gloss levels and dry times of the coatings as measured in the tests indicates that three complying interior coatings and three complying exterior coatings met the gloss and dry-time criteria for quick-dry enamels. Some of the coatings that were labeled as quick-dry enamels did not meet the criteria.

For the three interior coatings that met the quick-dry enamel criteria, all were water-based and had VOC levels that ranged from 178 g/l to 209 g/l. The three exterior coatings that met the quick-dry enamel criteria were also all water-based, and had VOC levels that ranged from 183 g/l to 257 g/l; the high end of that range is just over the proposed limit of 250 g/l ("low-VOC coatings"). There was one interior coating and four exterior coatings tested that had VOC levels above 250 g/l ("high-VOC coatings") from which to compare performance characteristics.

The results suggest that the low-VOC coatings had performance characteristics similar to the high-VOC coatings with regard to stability, hardness, application, adhesion, appearance, abrasion resistance, flexibility, accelerated weathering, impact resistance, and fungus resistance. In addition, the low-VOC coatings appeared to perform better than the high-VOC coatings with regard to accelerated yellowing and sag resistance. On the other hand, the high-VOC coatings appeared to perform better overall with regard to blocking resistance, although there was a high degree of variability in the results of this test, with some high-VOC products showing poor performance in this area and some low-VOC coatings showing good performance. (ARB, 1995; Cowen, 1999).

Product information from manufacturers

A number of products that are currently available satisfy the quick-dry enamel criteria and meet the proposed VOC limit. Product information sheets published by coatings manufacturers indicate that a number of coatings meet the gloss and dry time criteria of quick-dry enamels and have VOC levels at or below 250 g/l. The products we identified are all water-based, but the 250 g/l limit may not exclude all solvent-based coatings. At the end of this discussion are tables of information about specific products that meet the proposed VOC limit and, for comparison, products that exceed the proposed limit. We identified specific high-gloss quick-drying products with a VOC content of 250 g/l or less offered by Dunn Edwards, Evr-gard, ICI Dulux, Kelly Moore, and Sherwin-Williams. A list of performance characteristics compiled from product information sheets for such coatings is presented below and includes characteristics of products formulated for interior, exterior, and interior/exterior uses. Please note that not all high gloss, quick-drying coatings with VOC levels at or below 250 g/l possess all of the characteristics listed below:

High gloss, quick-drying coatings

highest premium finish, premium quality
very good non-blocking characteristics
excellent gloss retention
excellent color retention
alkyd-like hardness and durability
durable, exceptional toughness and durability, durable protection
dries quickly and cures to a washable finish
abrasion resistant
stands up to harsh use on interior surfaces
tough wear-resistant and weather-resistant finish
non-yellowing
high hiding
easy application
mildew resistant
excellent adhesion to aged alkyd enamels, excellent adhesion even to difficult surfaces
designed to prov