This listing is of equipment determined to be exempt from permit requirements under this regulation due to the relatively low potential to emit. An insignificant unit shall not include any unit subject to an applicable requirement other than District Rules 50 and 51.

(a) Any engines mounted on, within or incorporated into any vehicle, train, ship, boat or barge, that are used exclusively to provide propulsion, supply heat or electrical energy to that same vehicle, train, ship, boat, or barge, or that are used exclusively to load or unload cargo. Sand, rock, silt, soil or other materials which come from the bottom of a body of water shall not be considered cargo. This exemption is not intended to apply to equipment used for the dredging of waterways, to floating dry docks, or to equipment used in pile driving adjacent to or in waterways.

(b) Equipment utilized exclusively in connection with any structure, which is designed for and used exclusively as a dwelling for not more than four families.

(c) Air pollution control equipment associated with any article, machine, equipment, process or contrivance not required to have a permit to operate.

(d) The following equipment:

  1.  Internal combustion engines which fall into one of the following categories:
  1.  Water cooling towers and water cooling ponds not used for evaporative cooling of process water or not used for evaporative cooling of water, contaminated water or industrial waste water from barometric jets or from barometric condensers.
  2. Portable aircraft engine test stands which were constructed before November 4, 1976.
  3. Fuel-burning equipment as described below:
  1.  Extrusion equipment used exclusively for metals, minerals, or plastic except coking extrusion equipment or processes which manufacture products containing greater than one percent asbestos fiber by weight.
  2. Equipment used exclusively for forging, pressing, rolling or drawing of metals or for heating metals immediately prior to forging, pressing, rolling or drawing.
  3. All printing or graphic arts presses located at a stationary source which emits a total of less than 15 lbs of volatile organic compounds, subject to Rule 67.16, on each day of operation. It is the responsibility of any person claiming this exemption to maintain all usage records, including any mixing ratios, necessary to establish maximum daily emissions and to make this information available to the Air Pollution Control Officer upon request.
  4. Ovens, if only part of one or more processes which require a permit pursuant to these Rules and Regulations or which are exempt from a requirement for a permit to operate pursuant to this rule.
  5. Crucible-type or pot-type furnaces with a brimful capacity of less than 450 cubic inches of any molten metal.
  6. Crucible furnaces, pot furnaces or induction furnaces, with a capacity of 2500 cubic inches or less each, in which no sweating or distilling is conducted and from which only non-ferrous metals except yellow brass, are poured or non-ferrous metals are held in a molten state.
  7. Shell core and shell-mold manufacturing machines.
  8. Molds used for the casting of metals.
  9. Foundry sand mold forming equipment except those to which heat, sulfur dioxide or organic material is applied.
  10. Shot peening cabinets where only steel shot is employed and no scale, rust, or old paint is being removed.
  11. Die casting machines.
  12. Tumblers used for the cleaning or deburring of metal products without abrasive blasting.
  13. Metalizing guns, except electric arc spray guns, where the metal being sprayed is in wire form.
  14. Brazing, welding equipment including arc welding equipment.
  15. Hand soldering equipment and solder-screen processes. Solder-screen means those processes which use a process similar to silk-screening to apply solder and which subsequently undergo a reflow process other than a vapor phase solder reflow process.
  16. Equipment used exclusively for the sintering of glass or metals.
  17. Atmosphere generators and vacuum producing devices used in connection with metal heat treating processes.
  18. Dry batch mixers of 0.5 cubic yards (0.38 cubic meters) rated working capacity or less. Dry batch means material is added in a dry form prior to the introduction of a subsequent liquid fraction or when no liquid fraction is added.
  19. Batch mixers (wet) of 1 cubic yard (0.765 cubic meter) capacity or less where no organic solvents, diluents or thinners are used.
  20. Equipment used exclusively for the packaging of lubricants or greases.
  21. Portable conveyors (belt or screw type) where there is no screening.
  22. Roofing kettles (used to heat asphalt) with a capacity of 85 gallons (322 liters) or less.
  23. Abrasive blasting equipment with a manufacturer's-rated sand capacity of less than 100 pounds (45.4 kg) or 1 cubic foot or less.
  24. Abrasive blast cabinets which vent through control devices and into the buildings in which such cabinets are located.
  25. Blast cleaning equipment using a suspension of abrasive in water.
  26. Equipment used for buffing (except automatic or semi-automatic tire buffers) or polishing, carving, cutting, drilling, machining, routing, shearing, sanding, sawing, surface grinding, or turning of ceramic artwork, ceramic precision parts, leather, metals, rubber, fiberboard, masonry, except fiber reinforced plastics unless the process involves the use of water as a means for cutting and is equipped with a control device that does not emit to the atmosphere.
  27. Handheld equipment used for buffing, polishing, carving, cutting, drilling, machining, routing, sanding, sawing, surface grinding or turning of fiber reinforced plastic, when not used at a designated workstation, booth or room.
  28. Equipment used for carving, cutting, drilling, surface grinding, planning, routing, sanding, sawing, shredding or turning of wood, or the pressing or storing of sawdust, wood chips or wood shavings.
  29. Paper shredders and paper disintegrators which have a capacity of 600 pounds per hour or less.
  30. Equipment used to liquefy or separate oxygen, nitrogen or the rare gases from the air.
  31. Equipment used exclusively to grind, blend or package tea, cocoa, spices or roasted coffee.
  32. Equipment, other than boilers, used for preparing food for human consumption and located at eating establishments, bakeries and confectioneries, except for bakery ovens used for the baking of yeast leavened products which are located at a stationary source where the combined rated heat input capacity of all bakery ovens is equal to or more than two million Btu's per hour.
  33. Equipment using exclusively aqueous solutions not containing volatile organic compounds in excess of 10 percent by weight for surface preparation, cleaning, anodizing, plating, polishing, stripping or etching except acid chemical milling, chrome plating, chromic acid anodizing or the stripping of chromium, or copper etching using ammonium hydroxide, ammonium chloride or concentrated solutions of nitric, hydrofluoric and/or hydrochloric acids exceeding 17 percent acid concentration by weight.
  34. Laboratory equipment used exclusively for chemical or physical analyses and bench scale laboratory equipment provided such bench scale equipment is not used for production purposes to directly produce a deliverable product or service, other than the first-article product or service, and provided the emissions of organic compounds from such bench scale equipment, do not exceed five (5) pounds per day and provided such bench scale equipment does not emit detectable levels of compounds listed as Acutely Hazardous by Section 25532 of the California Health and Safety Code.
"Bench Scale Laboratory Equipment" shall mean equipment which a) is under direct, immediate and exclusive control of a laboratory director; b) is sub-scale in size; and c) is used for the sole purpose of conducting studies or tests to develop a new or improved product or service. 

"First-Article Deliverable Product or Service" shall mean the first product or service which is produced using bench scale laboratory equipment and which is delivered to a potential intra-company or external customer for approval. First article deliverable product or service shall not exceed one (1) unit of product or service per customer. 

  1. Titanium chemical milling at temperatures below 110¡F (43¡C).
  2. Orchard or citrus grove heaters.
  3. Non-immersion dry cleaning equipment.
  4. Alkaline chemical milling equipment for which construction or installation commenced prior to March 27, 1990, or alkaline chemical milling equipment used exclusively for the cleaning of internal combustion engine parts.
  5. Laundry dryers, extractors or tumblers used for fabrics cleaned only with solutions of bleach or detergents containing no organic solvents.
  6. Ovens having an internal volume of 27 cubic feet (0.765 cubic meter) or less in which organic solvents or materials containing organic solvents are charged.
  7. Equipment used for compression molding and injection molding of plastics.
  8. Cold solvent cleaning tanks, vapor degreasers, and paint stripping tanks
  1.  Railway sweepers used for cleaning rail tracks.
  2. Equipment used for powder coating operations, except metalizing gun operations, where surface preparation or cleaning solvent usage is less than one-half gallon each day.

(e) Stationary storage tanks (excluding tanks subject to Rule 61.9) for the storage of organic compounds, as follows:

  1. With a capacity of 260 gallons (984 liters) or less.
  2. With a capacity greater than 260 gallons (984 liters) provided that such containers, reservoirs or tanks will be used exclusively to store organic compounds that are not volatile organic compounds as defined in Rule 61.0.
  3. Used exclusively for the storage of organic solvents which are liquids at standard conditions and which are to be used as dissolvers, viscosity reducers, reactants, extractants, cleaning agents or thinners and not used as fuels.
  4. For the storage of natural gas or propane when not mixed with other volatile organic compounds as defined in Rule 61.0.
  5. Used exclusively as a source of fuel for wind machines used for agricultural purposes.

(f) Mobile transport tanks or delivery tanks or cargo tanks on vehicles used for the delivery of volatile organic compounds, except asphalt tankers used to transport and transfer hot asphalt used for roofing applications.

(g) Application equipment for architectural surface coatings as defined in Rule 67.0.

(h) Liquid surface coating application operations:

  1. Conducted within an application station (portable or stationary) where not more than 20 gallons per year of material containing organic compounds are applied. It is the responsibility of any person claiming this exemption to maintain purchase and daily usage records, including any mixing ratios, necessary to substantiate the claim. Coatings applied by means of non-refillable aerosol cans shall not be included in the annual usage determination for purposes of determining the 20 gallon per year limit stated above;
  2. Using non-refillable aerosol spray cans for application of coatings;
  3. Conducted outside defined coating areas for the purpose of touch-up or maintenance of equipment;
  4. Using hand-held brushes for application of a primer coating from containers of eight (8) ounces (236.6 milliliters) or less in size to fasteners to be installed on aerospace component parts;
  5. Using air brushes with a coating capacity of two (2) ounces (59.1 milliliters) or less for the application of a stencil coating; or
  6. Conducted in primary or secondary schools for instruction.

(i) The following uncontrolled equipment or processes using materials containing volatile organic compounds when the emissions of organic compounds from the equipment or process do not exceed five pounds in any one day:

  1. Foam manufacturing or application.
  2. Reinforced plastic fabrication using resins such as epoxy and/or polyester.
  3. Plastics manufacturing or fabrication.
  4. Ink mixing tanks.
  5. Cold solvent degreasers used exclusively for educational purpose.
  6. Batch-type waste-solvent recovery stills with batch capacity of 7.5 gallons or less for onsite recovery of waste solvent, provided the still is equipped with a device which shuts off the heating system if the solvent vapor condenser is not operating properly.
  7. Peptide Synthesis.
  8. Equipment used for washing or drying articles fabricated from metal, cloth, fabric or glass, provided that no organic solvent is employed in the process and that no oil or solid fuel is burned and none of the products being cleaned has residues of organic solvent..

The exemptions in this section shall not apply to equipment required to obtain a permit for emissions of air contaminants other than organic compounds.

(j) Vacuum cleaning systems used exclusively for housekeeping purposes.

(k) Back-pack power blowers.

(l) Structural changes which cannot change the quality, nature or quantity of air contaminant emissions.

(m) Repairs or maintenance not involving structural changes to any equipment for which a permit has been granted.

(n) Identical replacements in whole or part of any article, machine, equipment or other contrivance where a Permit to Operate had previously been granted for such equipment.

Identical replacement may also include replacement in whole or part of any article, machine, equipment or other contrivance where a Permit to Operate has previously been granted for such equipment which the Air Pollution Control Officer determines is identical in function, capacity, production rate and design. In addition, the actual air contaminant emissions must be the same in nature and will not be increased. Written notification of such replacement shall be made to the District at least thirty (30) days prior to the replacement and shall be accompanied by a fee of $75. Replacement of equipment pursuant to other requirements of these Rules and Regulations shall not be considered an identical replacement.

Identical replacement does not include replacements in whole or part that in sum would constitute reconstruction or modification under District Regulation X - Standards of Performance for New Stationary Sources, or would constitute a major source.

(o) Any article, machine, equipment, or contrivance other than an incinerator or boiler, the discharge from which contains airborne radioactive materials and which is emitted into the atmosphere in concentrations above the natural radioactive background concentration in air. "Airborne radioactive material" means any radioactive material dispersed in the air in the form of dusts, fumes, smoke, mists, liquids, vapors or gases. This exemption from the requirement to have a permit shall not include any emission unit subject to the provisions of Section 112 of the federal Clean Air Act or any implementing regulations promulgated by the federal EPA.

(p) The following equipment:

  1. Equipment used for hydraulic or hydrostatic testing.
  2. Equipment used exclusively for the dying or stripping (bleaching) of textiles where no organic solvents, diluents or thinners are used.
  3. Equipment used exclusively to mill or grind coatings and molding compounds where all materials charged are in a paste form and no organic solvents, diluents or thinners are used.
  4. Equipment used exclusively for the melting or applying of wax where no organic solvents, diluents or thinners are used.
  5. Equipment used for inspection of metal products except metal inspection tanks utilizing a suspension of magnetic or fluorescent dye particles in volatile organic solvent which have a liquid surface area greater than 5 ft2 and are equipped with spray type flow or a means of solvent agitation.
  6. Equipment used exclusively for the manufacture of water emulsions of asphalt, greases, oils or waxes.
  7. Equipment used exclusively for conveying and storing plastic pellets.
  8. Equipment used exclusively for the mixing and blending of materials at ambient temperature to make water-based adhesives.
  9. Curing or baking ovens in which no organic solvents or materials containing organic solvents are charged.
  10. Mixers for rubber or plastics where no material in powder form is added and no organic solvents, diluents or thinners are used.
  11. Each process line at a stationary source, as defined in Rule 20.1, for coating of pharmaceutical tablets provided maximum emissions of volatile organic compounds (defined in Rule 67.15), are below 15.0 pounds on each day for all operations subject to Rule 67.15. It will be the responsibility of any person claiming this exemption to maintain all records necessary to establish maximum daily emissions and to make this information available to the District upon request.
  12. Roll mills or calendars for rubber or plastics and no organic solvents, diluents or thinners are used.
  13. Vacuum-producing devices used in laboratory operations or in connection with other equipment which is exempt by Rule 11.
  14. Natural draft hoods, natural draft stacks or natural draft ventilators.
  15. Natural gas-fired or liquefied petroleum gas-fired or electrically heated furnaces for heat treating glass or metals, the use of which does not involve molten materials.
  16. Comfort air conditioning or comfort ventilating systems which are not designed to remove air contaminants generated by or released from specific units or equipment.
  17. Refrigeration units except those used as, or in conjunction with, air pollution control equipment.
  18. Equipment used exclusively for space heating, other than boilers.
  19. Equipment used exclusively for bonding lining to brake shoes.
  20. Lint traps used exclusively in conjunction with dry cleaning tumblers.
  21. Equipment used exclusively to compress or hold dry natural gas.
  22. Kilns used for firing ceramic ware, heated exclusively by natural gas, liquefied petroleum gas, electricity or any combination thereof.
  23. Equipment used exclusively for the purposes of flash-over fire fighting training.
  24. Wastewater processing units associated with drycleaning operations using halogenated compounds provided the water being evaporated in the unit does not exceed 400 ppm (by weight) of halogenated compounds as determined by EPA Test Method 634.
  25. Atmospheric organic gas sterilizer cabinets where ampules are utilized exclusively to dispense ethylene oxide gas into a liner bag and where total ethylene oxide emissions are less than five pounds per year.