Rule 74.7. Fugitive Emissions of Reactive Organic

Compounds at Petroleum Refineries and Chemical Plants

(Adopted 5/29/79, Revised 7/3/84, 1/10/89)

A. Applicability

The following provisions shall apply to petroleum refineries

and chemical plants.

B. Operating Requirements

1. A person shall not use any component, pump or

compressor if such component, pump or compressor leaks

reactive organic compounds into the atmosphere.

Emissions from components, pumps, or compressors which

have been tagged by the operator (as per Subsection

C.5) for repair or which have been repaired and are

awaiting re-inspection shall not be in violation of

this subsection.

2. Open-Ended Valves: All open-ended valves shall be

equipped with a cap, blind flange, plug, or a second

closed valve which is attached to seal the open end at

all times except during operations requiring process

fluid flow through the open-ended line. If a second

closed valve is used, the process side valve shall be

closed first, after operations requiring flow through

the open-ended valve.

3. Safety Relief Valves in Gas or Vapor Service:

a. Each safety relief valve shall be operated with

emissions no more than 200 ppm of ROC above

background, except when the process pressure

exceeds the limit setting specified for the


b. Each safety relief valve shall be returned to a

level of no more then 200 ppm of ROC above

background as soon as practicable after an

emergency release, but no later than 5 days after

the release.

4. Sampling Systems: Each sampling system shall collect

the purged process fluid for recycle or disposal with

no emission of a liquid containing reactive organic


C. Inspection Requirements

1. All safety relief valves shall be inspected quarterly

for leaks.

2. All components, pumps, and compressors shall be

inspected monthly for leaks according to procedures in

an Operator Management Plan approved by the Air

Pollution Control Officer.

3. If a component, pump, or compressor is found to be

not leaking for three consecutive monthly Operator

Management Plan inspections, then the component, pump,

or compressor shall be inspected not less than

quarterly, except for flanges, which shall be inspected

not less than annually.

4. Notwithstanding subsections C.2 and C.3, each pump

shall be visually inspected each day for leaks and

indications of leaks.

5. Upon detection of a leaking component, pump, or

compressor, a readily visible tag bearing the date on

which the leak is detected shall be affixed to that

component, pump, or compressor. The tag shall remain

in place until the leaking component, pump, or

compressor is repaired, reinspected, and found in

compliance with the requirements of this Rule.

6. Any component or equipment subject to this rule shall

be inspected for leaks within 24 hours if an indication

of a leak is found.

D. Repair Requirements

1. A leak shall be repaired as soon as practicable, but

no later than 15 days after detection. A first repair

attempt shall be made no later than 5 days after the

leak is detected. If repair is technically infeasible

without complete or partial process unit shutdown, the

repair shall be made during the next scheduled process

unit shutdown or turnaround, but not later than 90 days

from the date of leak detection, whichever occurs


2. A first repair attempt for a valve shall include, but

not be limited to tightening of bonnet bolts,

replacement of bonnet bolts, tightening of packing

gland nuts, or injection of lubricant into lubricated


E. Exemptions

A safety relief valve may be exempted from the requirements

of Subsections B.3 and C.1 if the safety relief valve is

inspected annually for leaks and either:

1. The emissions from the safety relief valve are vented

to a vapor recovery or disposal system that is at least

95% efficient, or

2. The safety relief valve is protected by a rupture

disc and there are no leaks. The rupture disc shall be

replaced no later than 5 days after a pressure release.

F. Operator Management Plan

1. Each operator of a petroleum refinery or chemical

plant shall submit an operator management plan to the

APCO. The APCO shall determine whether the operator

management plan meets the requirements of this rule and

notify the operator on the acceptance or rejection of

the plan. The operator management plan shall include

information that:

a. Identifies each process unit and, by diagram,

identifies each component (except for flanges),

pump, and compressor in the process unit subject

to the requirements of this rule,

b. Specifies the inspection schedule to be


c. Identifies maintenance procedures and practices

that will be taken to affect leak repairs on the

various components and equipment subject to this


d. Identifies process units which can not be

immediately shut down for leak repair, and

e. Identifies and describes any known hazard which

may affect the safety of an inspector.

2. For new facilities or modifications to a facility

covered under an existing Plan, the operator shall

submit a new or modified Plan to the APCO for approval

with the application for a Permit to Operate. If the

APCO fails to respond to the Plan in writing within 90

days, it shall be deemed approved.

G. Recordkeeping

1. Each operator subject to this rule shall maintain an

inspection log containing, at a minimum, the following


a. Name and location of any process unit where

leaking components or equipment are found,

b. Type of component or equipment, and

identification of process fluid,

c. Date of leak detection, and analyzer reading or

soap bubble score of the leak,

d. Date and analyzer reading or soap bubble score

on recheck after leak is repaired,

e. Leaks that cannot be repaired until process unit


f. Total number of components inspected, and total

number of leaking components found.

2. Copies of the inspection log shall be retained by the

operator for a minimum of 2 years after the date of an


3. Copies of the inspection log shall be available to

the APCD.

H. Reporting

No later than 15 days after the end of the previous quarter

each operator subject to this rule shall submit to the APCO

a report for the previous quarter's inspection and

maintenance activities which:

1. Summarizes the inspection log entries, and

2. Lists all leaking components identified that were not

repaired within 15 days and all leaking components

awaiting a unit turnaround for repairs.

I. Violations

The failure of a person to meet any requirement of this Rule

shall constitute a violation of this rule. Each leak

discovered by District personnel shall constitute a

violation of Section B.1. of this Rule.

It is the responsibility of the operator to demonstrate to

the satisfaction of the APCO, that a leak from a component

or equipment subject to this rule does not result in the

emission of reactive organic compounds to the atmosphere,

for that leak to be considered not a violation.

J. Definitions

1. "Appropriate Analyzer:" A hydrocarbon analyzer that

meets the requirements of EPA Reference Method 21 and

is calibrated with methane.

2. "Background" is defined as the ambient concentration

of reactive organic compounds determined at least 3

meters up-wind from the component or equipment to be

inspected and uninfluenced by any specific emission


3. "Chemical Plant:" Any facility engaged in producing

organic or inorganic chemicals and/or manufacturing

products by chemical processes. Any facility or

operation that has 282 as the first three digits in

their Standard Industrial Classification Code as

determined from the Standard Industrial Classification

Manual published in 1972 (or any more recent update) by

the Executive Office of the President, Office of

Management and Budget.

4. "Component:" Any valve, flange, connection,

diaphragm, hatch, sight glass, or meter.

5. "Indication of a Leak:"

a. The presence of a visible liquid mist, vapor, or

gas; or

b. The evidence of a potential leak found by

visual, audible, olfactory, or any other detection


6. "Leak:"

a. An emission of a liquid containing reactive

organic compounds at a rate of more than 3 drops

per minute, as a continuous stream, or as visible

mist; or

b. An emission of a gas containing reactive organic

compounds which causes an appropriate analyzer

sampling 1 centimeter from a source to register at

least 10,000 ppm as methane as determined by EPA

Reference Method 21, or

c.An emission of a gas containing reactive organic

compounds which causes a soap bubble score of 3 or


7. "Petroleum Refinery:" Any facility engaged in

producing gasoline, kerosene, distillate fuel oils,

residual fuel oils, lubricants, or other products

through distillation of petroleum or through

redistillation, cracking, rearrangement, or reforming

of unfinished petroleum derivatives.

8. "Soap Bubble Score" means the magnitude of a leak

using a standard soap bubble solution on a scale

equivalent to that defined in Attachment 1.


The soap bubble screening technique involves spraying a

solution of rug shampoo in distilled water (or glycol)

over all points of suspected leakage. Any escaping gas

will thus be encapsulated in bubbles, so that its volume

can be estimated. Soap scores are then assigned as

follows based on a six second observation:

Soap Score Estimate Bubble Volume (cc/6 Sec.)

0 No detectable bubbling

1 0 to 1 cc per 6 sec.

2 1 to 10 cc per 6 sec.

3 10 to 100 cc per 6 sec.

4 Greater than 100 cc per 6 sec.

Ref: p.17, "Assessment API/Rockwell Gas Plant

Fugitive Emissions Report - API Publication 4322" - Final

Report, by Radian Corporation for US EPA February 1981.