7/08 Rule 74.12: 1

VENTURA COUNTY AIR POLLUTION CONTROL DISTRICT 

RULE 74.12 - SURFACE COATING OF METAL PARTS AND PRODUCTS 

(Adopted 11/19/85, Revised 8/26/86, 5/16/89, 11/17/92, 1/10/95, 9/10/96, 11/11/03, 4/8/08) 

A. Applicability 

 The provisions of this rule apply to any person who applies or specifies the use of surface 

coatings to metal parts or products. 

 Any person who applies or specifies the application of surface coatings to either 

stationary structures or their appurtenances is subject to Rule 74.2 instead of this rule. 

 Any person who applies or specifies the application of surface coatings to aerospace 

vehicles or components is subject to Rule 74.13 instead of this rule. 

 Any person who applies or specifies the application of surface coatings to motor vehicles 

or mobile equipment or their parts or components is subject to Rule 74.18 instead of this 

rule. 

 Any person who applies or specifies the application of surface coatings to marine or fresh 

water vessels or their parts or components is subject to Rule 74.24 instead of this rule. 

 Any person who applies or specifies the application of surface coatings to pleasure craft 

or their parts or components or commercial boatyard operations is subject to Rule 74.24.1 

instead of this rule. 

B. Requirements 

1. Coating Reactive Organic Compounds (ROC) Content Limits: On or before July 

7, 2008, no person shall apply any coating with an ROC content in excess of the 

following limits, as applied: 

ROC Limits 

Grams Per Liter (g/L), or 

Pounds per Gallon (lb/gal) of Coating, 

Less Water and Exempt Organic Compounds 

 Air Dried Baked

 Coating g/L lb/gal g/L lb/gal

All coatings except 340 2.8 275 2.3 

for the following: 

Camouflage 420 3.5 360 3.0 

Extreme Performance 420 3.5 360 3.0 
7/08 Rule 74.12: 2 

Etching Filler 420 3.5 420 3.5 

Heat Resistant 420 3.5 360 3.0 

High Gloss 420 3.5 360 3.0 

High Performance 

 Architectural 420 3.5 420 3.5 

High Temperature 420 3.5 420 3.5 

Laboratory Furniture 340 2.8 340 2.8 

Metallic 420 3.5 360 3.0 

Mold Seal 420 3.5 420 3.5 

Pan Backing 420 3.5 420 3.5 

Pretreatment Wash Primer 340 2.8 275 2.3 

Silicone Release 420 3.5 420 3.5 

Solar Absorbent 420 3.5 360 3.0 

Vacuum Metalizing 420 3.5 420 3.5 

After July 7, 2008, no person shall apply any coating with an ROC content in 

excess of the following limits, as applied: 

ROC Limits 

Grams Per Liter (g/L), or 

Pounds per Gallon (lb/gal) of Coating, 

Less Water and Exempt Organic Compounds 

 Air Dried Baked

 Coating g/L lb/gal g/L lb/gal

All coatings except 275 2.3 275 2.3 

for the following: 

Multi-Component 

 not listed below 340 2.8 275 2.3 

Camouflage 420 3.5 360 3.0 

Extreme Performance 420 3.5 360 3.0 

Etching Filler 420 3.5 420 3.5 

Heat Resistant 420 3.5 360 3.0 

High Gloss 

 (Multi-Component) 420 3.5 360 3.0 

High Performance 

 Architectural 420 3.5 420 3.5 

High Temperature 420 3.5 420 3.5 

Metallic 420 3.5 360 3.0 

Mold Seal 420 3.5 420 3.5 

Pan Backing 420 3.5 420 3.5 

Pretreatment Wash Primer 340 2.8 275 2.3 

Silicone Release 420 3.5 420 3.5 

Solar Absorbent 420 3.5 360 3.0 
7/08 Rule 74.12: 3 

Vacuum Metalizing 420 3.5 420 3.5 

 2. Add-on Control Equipment Option: In lieu of complying with the coating ROC 

content limits specified in Subsection B.1, air pollution control equipment may be 

used provided: 

a. The combined capture and control device efficiency reduces emissions by 

at least 90 percent by weight, and 

b. The Air Pollution Control Officer (APCO) issues written approval for 

such equipment in the form of an Authority to Construct and Permit to 

Operate, and 

c. When operating a thermal incinerator, the combustion temperature of the 

incinerator is continuously monitored. 

d. When operating a catalytic incinerator, the exhaust and inlet gas 

temperatures of the incinerator are continuously monitored, and 

e. When operating a carbon adsorber or control device other than a thermal 

or catalytic incinerator, the control device efficiency is continuously 

monitored, and 

f. The equipment and monitors are used in accordance with vendor or 

manufacturer specifications. 

3. Transfer Efficiency: No person shall apply coatings subject to this rule except by 

using properly operated equipment and by using one or more of the following: 

a. Electrostatic application, operated at a minimum of 60 kV; 

b. Flow coat application; 

c. Dip coat application; 

d. High volume, low pressure application (HVLP); 

e. Hand application methods; 

f. Any other application method that is demonstrated to achieve at least 65 

percent transfer efficiency. 
7/08 Rule 74.12: 4 

 4. Surface Preparation and Cleanup:

a. After July 7, 2008, no person shall use a material for substrate surface 

cleaning that has an ROC content exceeding 25 grams per liter of material. 

 On or before July 7, 2008, no person shall use any material which contains 

more than 70 grams of ROC per liter of material for substrate surface 

cleaning. Substrate surface cleaning performed in a degreasing unit shall 

not be subject to this ROC content limit. 

b. After July 7, 2008, no person shall use a material for either spray 

equipment cleaning or cleanup that has an ROC content exceeding 25 

grams per liter of material. 

 On or before July 7, 2008, no person shall use organic solvent for cleanup 

unless: 

1) An enclosed gun washer or "low emission spray gun cleaner" that 

has been approved in writing by the APCO is properly used for 

spray equipment cleaning, and 

2) The ROC composite partial pressure of organic solvent used for 

cleanup, including spray equipment cleaning, is less than 45 mm 

Hg at 20 oC. 

 5. All ROC containing materials, including, but not limited to surface coatings, 

cleanup solvents, or surface preparation materials shall be stored in closed 

containers which are nonabsorbent and do not leak. 

 6. Coating Compliance Statement: The manufacturer of coatings subject to this rule 

shall designate on product labels or data sheets, the ROC content or the Volatile 

Organic Compounds (VOC) content of coatings including coating reducers and 

catalysts, as supplied. This designation shall include recommendations regarding 

thinning, reducing, or mixing with any other ROC containing materials, and 

express the coating ROC or VOC content on an as applied basis when used in 

accordance with the manufacturer's recommendations. All letters and numbers 

used to designate ROC or VOC content on product labels shall be visible and 

legible. 

 7. Liquid Cleaning Material Compliance Statement: The manufacturer of liquid 

cleaning materials used in coating operations shall designate on product labels or 

data sheets: 

 a. On or before July 7, 2008, the ROC content and ROC Composite Partial 

Pressure of cleaning materials as supplied. 
7/08 Rule 74.12: 5 

 b. After July 7, 2008, the ROC content of cleaning materials as supplied. 

This designation shall include recommendations regarding mixing with any other 

ROC containing materials, and express the cleaning material ROC content when 

used in accordance with the manufacturer's recommendations. All letters and 

numbers used to designate ROC or VOC content on product labels shall be visible 

and legible. 

 8. Prohibition of Specifications: No person shall specify, solicit or require the 

application of any coating to any metal part or product, or the use of any 

equipment cleaning solvent, if such application or use would violate this rule. 

This prohibition applies to all written and oral contracts for which any coating 

subject to this rule is to be applied to any metal part or product at any location in 

Ventura County. 

 9. Any person wishing to use a coating having an ROC content greater than that 

specified on his permit to operate shall apply for a permit modification. Such 

coating shall not have an ROC content exceeding the applicable limit specified in 

Subsection B.1. 

C. Exemptions 

 1. Subsection B.1 of this rule does not apply to any one coating provided: 

a. No complying coatings are available, and 

b. Total usage of all non-complying coatings has not exceeded 55 gallons in 

any calendar year. 

Any person claiming this exemption shall demonstrate the lack of available 

coatings to the APCO on an annual basis. 

2. This rule does not apply to: 

a. Aircraft or aerospace vehicle coating operations 

b. Marine vessel exteriors 

c. Motor vehicle and mobile equipment coating. 

d. Aerosol coating products. 

3. The provisions of this rule, except Subsection B.8, shall not apply to any 

stationary source that emits less than 200 pounds of ROC in every rolling period 

of 12 consecutive calendar months from metal parts and products coating 

operations. Any person claiming this exemption shall maintain monthly records 
7/08 Rule 74.12: 6 

to substantiate this claim. Emissions from aerosol products, cold cleaners, and 

vapor degreasers shall not be included in this determination. 

 4. Subsection B.4.a does not apply to any metal parts coating operation where total 

usage of non-complying substrate surface cleaners does not exceed five gallons 

per rolling 12-month period. Any person claiming this exemption shall maintain 

monthly operational records to substantiate this claim. 

D. Recordkeeping Requirements 

1. Any person subject to this rule shall: 

a. Maintain a current list of all coatings that provides all information 

necessary to evaluate compliance, including the following, as applicable: 

1) The name and manufacturer of each coating and any catalysts and 

reducers used with each coating 

2) Mix ratio of components used in coatings 

3) ROC content of coatings, as applied 

4) Coating category from Subsection B.1 of each coating used. 

b. Maintain records which show the following for each ROC containing 

material used for cleanup, including equipment cleaning, and each ROC 

containing material used for substrate surface cleaning: 

1) Type 

2) ROC content in grams per liter of material 

3) On or before July 7, 2008, composite ROC partial pressure of 

organic solvent (cleaning materials only). 

c. Maintain records of the monthly volume of each complying coating and 

ROC containing liquid used for equipment clean-up and surface 

preparation and daily volume of each noncompliant coating used. 

d. Any person using an emission control system as a means of complying 

with this rule shall maintain daily records of key system operating and 

maintenance procedures which will demonstrate continuous operation and 

compliance of the emission control device during periods of emission 

producing activities. Key system operating parameters are those necessary 

to ensure compliance with subsection B.2 such as temperatures, pressures 

and flow rates. 
7/08 Rule 74.12: 7 

 2. All lists and records shall be maintained for a minimum of two (2) years from the 

date of each entry and shall be available to District personnel upon request. 

E. Test Methods 

1. The reactive organic compounds content of coatings and liquid cleaning materials, 

shall be determined using EPA Reference Method 24 (40 CFR 60, Appendix A). 

2. Transfer efficiency shall be determined in accordance with the South Coast Air 

Quality Management District method entitled "Spray Equipment Transfer 

Efficiency Test Procedure for Equipment Users." 

 3. ROC composite pressure of a solvent shall be calculated using a widely accepted 

published source such as: Boublik, T., V. Fried and E. Hala, "The Vapor Pressure 

of Pure Substances," Elsevier Scientific Publishing Co., New York (1973), Perry's 

Chemical Engineer's Handbook, McGraw-Hill Book Company, CRC Handbook 

of Chemistry and Physics, Chemical Rubber Publishing Company (1986-87), and 

Lange's Handbook of Chemistry, John A. Dean, editor, McGraw-Hill Book 

Company (1985). The true vapor pressure of a component in a solvent mix may 

be determined by ASTM Method D2879-86. The ROC composite pressure of a 

solvent mix consisting entirely of ROC may be determined by ASTM Method 

D2879-86. 

4. Capture efficiency shall be determined according to EPA Guidelines for 

Determining Capture Efficiency, dated January 9, 1995, and 40 CFR 51, 

Appendix M, Methods 204-204F as applicable. Control device efficiency shall be 

determined by 40 CFR 60, Appendix A, Methods 18, 25 or 25A. 

5. The acid content of pretreatment wash primers and etching fillers shall be 

determined by ASTM D1613-85. 

6. The solids content of etching fillers shall be determined using EPA Reference 

Method 24. 

7. The metal content of metallic coatings shall be determined by Spectrographic 

Method 311 in the South Coast Air Quality Management District manual, 

"Laboratory Methods of Analysis for Enforcement Samples." 

8. The active and passive solvent losses from spray gun cleaning systems shall be 

determined using South Coast Air Quality Management District's "General Test 

Method for Determining Solvent Losses from Spray Gun Cleaning Systems" dated 

October 3, 1989. The test solvent for this determination shall be any lacquer 

thinner with a minimum vapor pressure of 105 mm Hg at 20o C. The minimum 

test temperature shall be 15o C. 
7/08 Rule 74.12: 8 

9. High Volume-Low Pressure (HVLP) equipment shall be identified by either test 

air cap measurements or an inlet pressure measurement that, when used with 

specifications published by the manufacturer, establishes that gun is being 

operated as specified in Subsection G.24. 

F. Violations 

Failure to comply with any provision of this rule, including the maintenance of records, is 

a violation of this rule. 

G. Definitions 

1. "Active Solvent Losses": Emissions during all steps of a spray gun equipment 

cleaning operation, expressed as grams of solvent loss per cleaning cycle. 

2. "Aerosol Coating Product": A pressurized coating product containing pigments or 

resins that dispenses product ingredients by means of a propellant, and is 

packaged in a disposable can for hand held application, or for use in specialized 

equipment for ground traffic/marking applications. 

3. "Aircraft or Aerospace Vehicle": A fabricated part, assembly of parts or 

completed unit of any aircraft, helicopter, missile or space vehicle. 

4. "Air-Dried Coating": Any coating which is not heated above 90oC (194oF) for 

the purpose of curing or drying. 

5. "Baked Coating": Any coating which is cured or dried in an oven where the oven 

air temperature exceeds 90oC (194oF).

6. "Camouflage Coating": A coating that functions to conceal equipment from 

detection. 

7. "Capture Efficiency": The percentage of ROC used, emitted, evolved, or 

generated by the operation, that are collected and directed to an air pollution 

control device. 

8. "Carbon Adsorber": A device that adsorbs ROC from a gaseous stream onto the 

surface of activated carbon. 

9. "Catalytic Incinerator": A device that burns ROC in air using a material that 

increases the rate of combustion without itself undergoing a net chemical change 

in the process. Common catalyst materials include but are not limited to, 

platinum alloys, chromium, copper oxide, and cobalt. 
7/08 Rule 74.12: 9 

10. "Cleanup": The removal of uncured coating from any surface. 

11. "Coating": A material applied to a metal surface as a film to beautify and/or 

protect the surface. 

12. "Control Device Efficiency": The percentage by weight of ROC entering a 

control device that is not emitted to the atmosphere. 

13. "Electrostatic Application": The charging of atomized paint droplets to cause 

deposition by electrostatic attraction. 

14. "Etching Filler": A coating that contains less than 23 percent solids by weight and 

at least 1/2 percent acid by weight, and is used instead of a pretreatment wash 

primer on a metal substrate prior to a primer. 

15. "Exempt Organic Compounds": As defined in Rule 2, Definitions, of these rules. 

16. "Extreme Performance Coating": Any coating except a zinc filled primer, a 

laboratory furniture coating, or a pretreatment coating that is exposed to any of the 

following conditions: 

a. Industrial-grade detergents, cleaners, or abrasive scouring agents. 

b. Unprotected shipboard conditions. 

c. Frequent or chronic exposure to salt water, corrosives, caustics, acids, or 

oxidizing chemicals. 

d. Other similar or more harsh environmental conditions as determined in 

writing by the APCO. 

17. "Grams of ROC per liter of coating, less water and exempt organic compounds": 

The weight of ROC per combined volume of ROC and coating solids calculated 

as follows: 

 Grams of ROC per Liter of Coating Ws - Ww - Wes

 Less Water and Less Exempt Organic Compounds = Vm - Vw - Ves 

Where: 

Ws = Weight of volatile compounds (grams) 

Ww = Weight of water (grams) 

Wes = Weight of exempt organic compounds (grams) 

Vm = Volume of material (liters) 

Vw = Volume of water (liters) 

Ves = Volume of exempt organic compounds (liters) 
7/08 Rule 74.12: 10 

18. "Grams of ROC per liter of material": The weight of ROC per volume of material 

calculated as follows: 

 Grams of ROC per Liter of Material = Ws - Ww - Wes

 Vm 

Where: 

Ws = Weight of volatile compounds (grams) 

Ww = Weight of water (grams) 

Wes = Weight of exempt organic compounds (grams) 

Vm = Volume of material (liters) 

19. "Gun Washer": Electrically or pneumatically operated system that is designed to 

clean spray application equipment while enclosed. A gun washer may also be 

considered a gun cleaning system that consists of spraying solvent into an 

enclosed container using a snug fitting. 

20. "Hand Application Methods": The application of coatings by nonmechanical 

hand-held equipment including but not limited to paint brushes, hand rollers, 

caulking guns, trowels, spatulas, syringe daubers, rags and sponges. 

21. "Heat Resistant Coating": Any applied coating that, after curing, must withstand a 

temperature of at least 204o C (400o F) during normal use. 

22. "High Gloss Coating (Multi-Component)": Any multi-component coating which 

when tested in accordance with ASTM Test Method D523-89 has a reflectance of 

85 percent or more on a 60 degree meter. 

23. "High Performance Architectural Coating": Any coating used to protect 

architectural subsections and which is required to meet the specifications of the 

Architectural Aluminum Manufacturer Association's publication number AAMA 

605.2-1992. 

24. "High Temperature Coating": Any coating that after curing, must withstand a 

temperature of at least 538 oC (1000 oF) during normal use. 

25. "High Volume-Low Pressure Application (HVLP)": Equipment used to apply 

coatings by means of a spray gun designed to be operated and operated between 

0.1 and 10 pounds per square inch gauge (psig) air pressure measured dynamically 

at the center of the air cap and at the air horns. 

26. "Leak": The dripping of three or more drops per minute of ROC containing 

liquids. 

27. "Low Emissions Spray Gun Cleaner": Any properly used spray equipment 

cleanup device which has passive solvent losses of no more than 0.6 grams per 
7/08 Rule 74.12: 11 

hour and has active solvent losses of no more than 15 grams per operating cycle as 

determined by the test method in Subsection E.8. 

28. "Metallic Coating": Any coating, except zinc filled primer, which contains 5 

grams of metal particles per liter of coating, as applied, where such particles are 

visible in the dried film. 

29. "Metal Part or Product": Any component or complete unit fabricated from metal, 

not including stationary structures or their appurtenances, marine vessel exteriors, 

aerospace vehicles and components, and motor vehicles and mobile equipment. 

30. "Mold-Seal Coating": The initial coating applied to a new or repaired mold to 

prevent products from sticking to the mold. 

31. "Multi-Component Coating": A coating requiring the addition of one or more 

separate components, commonly known as catalyst or hardener, prior to 

application to form an acceptable dry film. 

32. "One-Component Coating": Any coating that is ready for application as it comes 

out of its container to form an acceptable dry film. A thinner or reducer, 

necessary to reduce the viscosity, is not considered a component. 

33. "Operation": The coating, surface preparation, and cleaning of metal parts or 

products and any associated activities including but not limited to the cleaning of 

coating application equipment. 

34. "Pan Backing Coating": Any coating applied to the surface of pots, pans, or other 

cooking utensils that are exposed directly to a flame or other heating elements. 

35. "Passive Solvent Losses:" Emissions resulting from natural vaporization of 

solvent from spray gun cleaning equipment not being used in a cleaning cycle. 

36. "Powder Coating": Any coating applied as fine particle solids with less than 4 

percent by weight ROC or other liquid carriers. 

37. "Pretreatment Wash Primer": Any coating which contains at least one half 

percent acid by weight to provide surface etching, corrosion resistance, adhesion, 

and ease of stripping when applied to a metal surface. 

38. "Reactive Organic Compounds": As defined in Rule 2, Definitions, of these rules. 

39. ROC Composite Partial Pressure": The sum of the partial pressures of the 

compounds defined as ROCs. ROC composite partial pressure is calculated as 

follows: 
7/08 Rule 74.12: 12 

( )( )

( ) PP

W VP

MW

W

MW

W

MW

W

MW

c

i i

i i

n

w

w

e

e e

n i

i i

n = 



 



 + 



 



 + 



 





=

= =

∑

∑ ∑

1

1 1

 Where: 

 Wi = Weight of the "i"th ROC compound, in grams 

 Ww = Weight of water, in grams 

 We = Weight of the "e"th exempt organic compound, in grams 

MWi = Molecular weight of the "i"th ROC compound, in g/(g-mole) 

 MWw = Molecular weight of water, in g/(g-mole) 

 MWe = Molecular weight of the "e"th exempt compound, in g/(g-mole) 

 PPc = ROC composite partial pressure at 20 C, in mm Hg 

 VPi = Vapor pressure of the "i"th ROC compound at 20 C, in mm Hg. 

40. "ROC Content": For coatings, ROC (VOC) content means the grams of ROC per 

liter of coating, less water and less exempt organic compounds. For liquid 

cleaning materials and other ROC containing materials, ROC content means the 

grams of ROC per liter of material. 

41. "Silicone Release Coating": Any coating which contains silicone resin and 

functions to prevent food from sticking to metal surfaces such as baking pans. 

42. "Solar Absorbent Coating": Any coating which has as its prime purpose the 

absorption of solar radiation. 

43. "Substrate Surface Cleaning": Cleaning of a substrate to remove dirt, oils, and 

other contaminants. Substrate surface cleaning is typically done prior to the 

application of surface coatings, adhesive bonding materials, or sealants. 

44. "Thermal Incinerator": A device that burns ROC in air by direct application of 

heat. Thermal incinerators are usually equipped with burners, refractory lined 

chambers, heat recovery equipment, and process controllers. 

45. "Transfer Efficiency": The ratio of the weight of coating solids adhering to the 

part being coated to the weight of coating solids used in the application process 

expressed as a percentage. 

46. "Vacuum Metalizing Coating": Any undercoat applied to a substrate prior to 

application of a metal film, or an overcoat applied directly to the metal film. 

47. "Volatile Organic Compounds (VOC)": Reactive organic compounds (ROC). 

48. "Zinc Filled Primer": Any coating which has an elemental zinc content of not less 

than 240 grams/liter (2.0 pounds per gallon) as applied.