Imperial County Air Pollution Control District Rule 427

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RULE 427 AUTOMOTIVE REFINISHING OPERATIONS

(Adopted 9/14/99: Revised __/__/__)

A. General

A.1 Purpose

The purpose of this Rule is to limit the emission of Volatile Organic 

Compounds from the Finishing or Refinishing of Motor Vehicles, Mobile 

Equipment and their parts and components.

The purpose of this rule is to limit Volatile Organic Compound (VOC) 

emissions from coatings and solvents associated with the coating of motor 

vehicles, mobile equipment, and associated parts and components.

A.2 Applicability

A.2.a Except as provided in section A.2.b, this rule is applicable to any 

person who supplies, sells, offers for sale, manufactures, or 

distributes any automotive coating or associated solvent for use

within the District, as well as any person who uses, applies, or 

solicits the use or application of any automotive coating or 

associated solvent within the District.

A.2.b This rule does not apply to:

A.2.b.1 Any Automotive coating or associated solvent that is 

offered for sale, sold, or manufactured for use outside 

of the District or for shipment to other manufacturers 

for reformulation or repackaging.

A.2.b.2 Any aerosol coating product

A.2.b.3 Any automotive coating that is sold, supplied, or 

offered for sale in 0.5 fluid ounce or smaller 

containers intended to be used by the general public 

to repair tiny surface imperfections.

A.2.b.4 Any coating applied to motor vehicles or mobile 

equipment, or their associated parts and components, 

during manufacture on an assembly line.

This Rule applies to any facility engaged in the assembly of or Refinishing 

of Group I (buses and Mobile Equipment) and Group II (passenger cars, 

Large/Heavy Duty Truck cabs and chassis, Light and Medium Duty Trucks 

and Vans, and motorcycles) vehicles, when the process(es) utilize any of 
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the products specified in subsection C.1.a of this Rule.

B. Definitions

The following terms used in this Rule are defined in Rule 101 - Definitions:

Additive; Anti-Glare/Safety Coating; Camouflage Coating; Catalyst; Coating; 

Color Match; Electrostatic Application; Extreme Performance Coating; Finish; 

Graphic Design Application; Group I Vehicles; Group II Vehicles and Equipment; 

High-Volume, Low-Pressure (HVLP) Spray; Large/Heavy Duty Trucks; Light and 

Medium Duty Trucks and Vans; Metallic Topcoat; Mobile Equipment; 

Multicolored Topcoat; Pretreatment Wash Primer; Primer; Primer Sealer; Primer 

Surfacer; Reducer; Refinishing; Specialty Coatings; Spot/Panel Repair; Surface 

Preparation Solvent; Topcoat; Touch-up Coating; Transfer Efficiency.

For the purpose of this Rule the following definitions shall apply:

B.1 VOC Content

B.1.a “VOC regulatory for Coatings” means VOC in grams per liter of 

coating, excluding water and exempt compounds, and shall be 

calculated by the following equation:

GVOCVOC regulatory content = WSv - WW - WESec

VMm - Vw - Vesec

B.1.b “VOC actual for Coatings” means VOC in grams per liter of 

material shall be calculated using the following equation:

VOC actual content = Wv - WW - Wec

Vm

B.1.c “VOC content for Solvents” means VOC in grams per liter of 

material shall be calculated using the following equation:

VOC content = Wv - WW - Wec

Vm

Where: GVOC = Grams VOC/L of Coating less water and Exempt Compounds

VOC content = amount of volatile organic compounds in grams/liter

Wv = weight of volatiles in grams

Ww = weight of water in grams

Wec = weight of exempt compounds in grams

Vm = volume of material (coating or solvent, as applicable) in liters
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Vw = volume of water in liters

Vec = volume of exempt compounds in liters

GRAMS OF VOC PER LITER OF Coating LESS WATER AND LESS EXEMPT 

COMPOUNDS: the weight of VOC per combined volume of VOC and Coating 

solids is calculated by the following equation:

WS = weight of volatile compounds in grams

WW = weight of water in grams

WES = weight of Exempt Compounds in grams

VM = volume of material in liters

VW = volume of water in liters

VES = volume of Exempt Compounds in liters

MULTI-STAGE TOPCOAT SYSTEM: a Topcoat system composed of either a 

basecoat/clearcoat, a basecoat/midcoat/clearcoat, or a 

groundcoat/basecoat/midcoat/clearcoat. The VOC content of a multi-stage 

Topcoat system shall be determined according to the following formulas:

For a basecoat/clearcoat system:

 VOCbc + 2VOCcc

VOCMS = 3

For a 3 Stage Coating system:

 VOCbc + VOCmc + 2VOCcc

VOCMS = 4

For a 4 Stage Coating system:

VOCMS = VOCgc + VOCbc + VOCmc + 2VOCcc5

Where VOCMS is the average of the VOC content, as applied, and used to 

determine compliance with the standards in subsection C.1.a.1.

VOCgc is the VOC content, as applied of a pigmented groundcoat or tinted 

Primer Sealer.

VOCbc is the VOC content, as applied, of a pigmented basecoat.

VOCmc is the VOC content, as applied, of a translucent midcoat.
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2VOCcc is two times the VOC content, as applied, of a transparent 

clearcoat.

VOLATILE ORGANIC COMPOUND is any compound containing at least 

one atom of carbon, except for the following compounds and solvents: 

methane, carbon monoxide, carbon dioxide, carbonic acid, metallic 

carbides or carbonates, ammonium carbonate, 1, 1,1-trichloroethane, 

methylene chloride, trichlorofluoromethane (CFC-11), 

dichlorodifluoromethane (CFC-12), chlorodifluoromethane (HCFC-22), 

trifluoromethane, (HFC-23), 1,1,12-trichloro-21,2,2-trifluoroethane (CFC113), 1,2-dichloro- 1,1,2,2-tetrafluoroethane (CFC-114), 

chloropentafluoroethane (CFC-115), 2,2-dichloro-1.1.1-trifluoroethane 

(HCFC-123), 2-chloro-1,1,1,2-tetrafluoroethane (HCFC-124), 

pentafluorethane (HFC-125), 1,1,2,2-tetrafluoroethane (HFC-134), 1,1,1,2-

tetrafluoroethane (HFC-134a), 1,1-dichloro-1-fluoroethane (HCFC-141b), 

1-chloro-1,1-difluoroethane (HCFC-142b), 1,1,1-trifluoroethane (HFC143a), 1,1-difluoroethane (HFC-152a), and the following four classes of 

perfluorocarbon (PFC) compounds:

1. cyclic, branched, or linear, completely fluorinated alkanes,

2. cyclic, branched, or linear, completely fluorinated ethers with no 

unsaturations,

3. cyclic, branched, or linear, completely fluorinated tertiary amines 

with no unsaturations, and

4. saturated perfluorocarbons containing sulfur with sulfur bonds only 

to carbon and fluorine.

C. Standards

C.1 Coating Limits

No person shall apply to any motor vehicle, mobile equipment, or 

associated parts and components, any coating with a VOC regulatory 

content, as calculated pursuant to subsection B.1.a, in excess of the 

following limits, except as provided in section C.3:

Coating Category VOC regulatory limit, as applied, in 

grams/liter (pounds per gallon*)

Effective 

April 1, 2010

Adhesion Promoter 540 (4.5)

Clear Coating 250 (2.1)
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Coating Category VOC regulatory limit, as applied, in 

grams/liter (pounds per gallon*)

Effective 

April 1, 2010

Color Coating 420 (3.5)

Multi-Color Coating 680 (5.7)

Pretreatment Coating 660 (5.5)

Primer 250 (2.1)

Primer Sealer 250 (2.1)

Single-Stage Coating 340 (2.8)

Temporary Protective Coating 60 (0.5)

Truck Bed Liner Coating 310 (2.6)

Underbody Coating 430 (3.6)

Uniform Finish Coating 540 (4.5)

Any other coating type 250 (2.1)

*English units are provided for information only.

C.1.a Any Person who applies Coating to Group I or II vehicles, Mobile 

Equipment, their parts and components, shall comply with 

subsections C.1.a.1 or C.1.a.2 below:

C.1.a.1Group I Vehicles and Mobile Equipment: Any Person shall 

not Finish or refinish Group I Vehicles and Equipment or 

their parts and components where Color Match is not 

required, using any Coating with a VOC content in excess of 

the following limits, expressed as grams of VOC per liter (or 

pounds per gallon) of Coating, as applied excluding water 

and exempt solvents, unless emissions of VOC to the 

Atmosphere are controlled by air pollution abatement 

Equipment with combined Capture Efficiency and Control 

Efficiency of the abatement device of at least 85 percent, 

and which has been approved in writing by the Air Pollution 

Control Officer:

 VOC Limits

Pretreatment Wash Primer 780 g/L (6.5 lbs/gal)

Primer 420 g/L (3.5 lbs/gal)

Primer Sealer 420 g/L (3.5 lbs/gal)

Primer Surfacer 420 g/L (3.5 lbs/gal)

TOPCOATS

 Metallic Topcoat 420 g/L (3.5 lbs/gal)

 Extreme Performance 420 g/L (3.5 lbs/gal)

 Multicolored 685 g/L (5.7 lbs/gal)

 Camouflage Coating 420 g/L (3.5 lbs/gal)
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 All Other Topcoats 420 g/L (3.5 lbs/gal)

C.1.a.2Group II Vehicles: Any Person shall not refinish Group II 

Vehicles, their parts and components, or Group I Vehicles 

and Mobile Equipment where Color Match is required, using 

any Coating with a VOC content in excess of the following 

limits, expressed as grams of VOC per liter (or pounds per 

gallon) of Coating as applied, excluding water and exempt 

solvents, unless emission of VOC to the Atmosphere are 

controlled by air pollution abatement Equipment with a 

combined Capture Efficiency and Control Efficiency of the 

abatement device efficiency of at least 85 percent, and 

which has been approved in writing by the Air Pollution 

Control Officer:

VOC Limits

Pretreatment Wash Primer 780 g/L (6.5 lbs/gal)

Primer/Primer Surfacer 420 g/L (3.5 lbs/gal)

Primer Sealer 420 g/L (3.5 lbs/gal)

TOPCOATS

Metallic Topcoat 520 g/L (4.3 lbs/gal)

Multistage Topcoat System 540 g/L (4.5 lbs/gal)

Multicolor 685 g/L (5.7 lbs/gal)

 Multicolor Multistage 480 g/L (4.0 lbs/gal)

 All Other Topcoats 420 g/L (3.5 lbs/gal)

Speciality Coating 840 g/L (7.0 lbs/gal)

C.2 Most Restrictive VOC Limit

If anywhere on the container of any automotive coating, or any label or 

sticker affixed to the container, or in any sales, advertising, or technical 

literature supplied by a person, any representation is made that indicates 

that the coating meets the definition of or is recommended for use for 

more than one of the coating categories listed in section C.1, then the 

lowest VOC content limit shall apply.

C.2 Transfer Efficiency

C.2.a For all Coatings, any Person shall not apply any Coating to any 

Group I or II vehicles or Mobile Equipment or their parts and 

components unless one of the following methods is used:

C.2.a.1Electrostatic Application Equipment, operated in accordance 

with the manufacturer's recommendations;

C.2.a.2High Volume Low Pressure (HVLP) spray Equipment, 
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operated in accordance with the manufacturer's 

recommendations;

C.2.a.3Any other Coating application which has been demonstrated 

to the satisfaction of the Air Pollution Control Officer to be 

capable of achieving at least 65 percent Transfer Efficiency, 

as per section G.2.c, and for which written approval of the 

Air Pollution Control Officer has been obtained.

C.3 Alternative Compliance

Instead of complying with the VOC content limits specified in section C.1, 

a person may use an emission control system that has been approved, in 

writing, by the Executive Officer or Air Pollution Control Officer of the 

District and which achieves an overall control efficiency of at least 85 

percent as determined pursuant to sections E.5 and E.6. Any approved 

system emission control must be maintained and used at all times in 

proper working condition. 

C.3 Prohibition of Specification

No Person shall solicit or require for use or specify the application of a 

Coating on a Group I or II vehicle, Mobile Equipment, or part or 

component thereof if such use or application results in a violation of the 

provisions of this Rule. The prohibition of this section shall apply to all 

written or oral contracts under the terms of which any Coating which is 

subject to the provisions of this Rule is to be applied to any Motor Vehicle, 

Mobile Equipment, or part or component at any physical location within the 

District.

C.4 Prohibition of Possession

No person shall possess at any automotive refinishing facility, any 

automotive coating that is not in compliance with section C.1 or C.3, as 

applicable. Effective April 1, 2010, no person shall possess at any 

automotive refinishing facility, any solvent with a VOC content greater than 

25 grams per liter.

C.4 Prohibition of Sale

No Person shall offer for sale or sell within the District any Coating that 

does not meet the VOC content limits as set forth in subsection C.1.a of 

this Rule. The prohibition of this section shall apply to the sale of any 

Coating which will be applied at any physical location within the District.

C.5 Prohibition of Sale or Manufacture
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No person shall manufacture, blend, repackage for sale, supply, sell, offer 

for sale, or distribute within the District any coating with a VOC content in 

excess of the limits specified in section C.1.

Notwithstanding the provisions of this section, a person may manufacture, 

blend, repackage for sale, supply, sell, offer for sale, or distribute a coating 

with a VOC content in excess of the limits specified in section C.1 under 

the following circumstances and provided all of the requirements of 

section D.6 are also met:

C.5.a The coating is for use exclusively within an emission control 

system as allowed in section C.3, or

C.5.b The coating is for use outside the District.

C.5 Compliance Statement Requirement

The manufacturer of Coatings subject to this Rule shall include a 

designation of VOC as supplied on data sheets; including Coating 

components, expressed in gram per liter or pounds per gallon, excluding 

water and exempt solvents.

C.6 Prohibition of Specification

No person shall solicit or require the use of, or specify the application or 

use of any coating or solvent on a motor vehicle or mobile equipment, or 

associated parts and components, if such use or application results in a 

violation of this rule. This prohibition shall apply to all written or oral 

contracts, including, but not limited to, job orders, under the terms of which 

any coating or solvent that is subject to the provisions of this rule is to be 

used or applied. This prohibition shall not apply to coatings that meet the 

criteria specified in section C.5.

C.6 Surface Preparation and Cleanup Solvent

The requirements of this section shall apply to any Person using solvent 

for surface preparation and cleanup.

C.6.a Any Person shall not use an organic compound(s), or mixture 

thereof, (excluding Exempt Compounds) for surface preparation 

with a VOC content in excess of 200 grams per liter (1.67 pounds 

per gallon) of material, as applied.

C.6.b Any Person shall use closed, non-absorbent containers for the 

storage or disposal of any applicator (including brushes, swabs, 
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cloth or paper) used for solvent surface preparation and cleanup.

C.6.c Any Person shall store fresh or open solvent in closed containers.

C.6.d Any Person shall not use organic compounds for the cleanup of 

spray Equipment including paint lines unless an enclosed system is 

used for cleanup. The system shall enclose spray guns, cups, 

nozzles, bowls, and other parts during washing, rinsing and 

draining procedures. Equipment used shall minimize the 

evaporation of organic compounds to the Atmosphere.

C.7 Coating Application Methods

No person shall apply any coating to any motor vehicle, mobile equipment, 

or associated parts and components unless one of the following 

application methods is used:

C.7.a Brush, dip or roller.

C.7.b Electrostatic spray.

C.7.c High-Volume Low-Pressure (HVLP) spray equipment

C.7.d Use of a spray gun: If a spray gun is used, the end user must 

demonstrate that the gun meets the HVLP definition found in 

Rule 101 Definitions in design and use. A satisfactory 

demonstration must be based on the manufacturer’s published 

technical material on the design of the gun and by a 

demonstration of the operation of the gun using an air pressure 

tip gauge from the manufacturer of the gun.

C.7.e Any alternative method that achieves a transfer efficiency 

equivalent to, or higher than, the application methods listed in 

sections C.7.a, C.7.b, or C.7.c as determined per section E.9. 

Written approval from the Executive Officer or Air Pollution 

Control Officer shall be obtained for each alternative method 

prior to use.

Section C.7 does not apply to underbody coatings, graphic arts 

operations, truck bed liner coatings, or any coating use of less than one 

(1) fluid ounce (29.6 milliliters).

C.7 Any Person shall not use any speciality Coating with a VOC content, as 

applied, in excess of 840 g/L (7.0 lbs/gal), excluding water and exempt 

solvents. Use of all speciality Coating except anAnti-Glare/Safety Coating 

glare/safety Coatings shall not exceed 5.0 percent of all Coating, applied, 
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averaged on a monthly basis. The application of Topcoats with a 

Specialty Coating used as an Additive shall be subject to the Topcoat 

limits in subsections C.1.a.1 or C.1.a.2.

C.8 Solvent Limits and Evaporative Loss Minimization

C.8.a Effective April 1, 2010, each solvent present at any automotive 

refinishing facility shall not exceed a VOC content of 25 grams 

per liter as calculated pursuant to section B.1.c.

C.8.b Solvent-laden materials shall be stored in closed containers.

C.8.c All automotive coating components, automotive coatings, and 

solvents shall be stored in closed vapor-tight containers.

C.8.d No person shall clean spray equipment unless a closed system 

is used. However, equivalent control equipment can be used if 

the Executive Officer or Air Pollution Control Officer of the 

District approves it in writing prior to use.

C.8.e All waste automotive coating components, automotive coatings, 

and solvents shall be stored in closed vapor-tight containers, 

except while adding to or removing them from the containers.

C.8. Any Person seeking to use an Extreme Performance Coating in any 

Coating operation which is subject to this Rule shall comply with the 

requirements of subsection E.1.a.

D. Administrative Requirements Exemptions

D.1 Compliance Statement Requirement

D.1.a For each individual automotive coating or automotive coating 

component, the manufacturer and repackager shall include the 

following information on product data sheets, or an equivalent 

medium:

D.1.a.1 The VOC actual for coatings and VOC regulatory for 

coatings, expressed in grams per liter;

D.1.a.2 The weight percentage of volatiles, water, and exempt 

compounds;

D.1.a.3 The volume percentage of water and exempt 

compounds; and,
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D.1.a.4 The density of the material (in grams per liter).

D.1.b For each individual ready to spray mixture (based on the 

manufacturer’s and repackager’s stated mix ration), the 

manufacturer and repackager shall include the following 

information on product data sheets, or an equivalent medium:

D.1.b.1 The VOC actual for coatings and VOC regulatory for 

coatings, expressed in grams per liter;

D.1.b.2 The weight percentage of volatiles, water, and exempt 

compounds;

D.1.b.3 The volume percentage of water and exempt 

compounds; and,

D.1.b.4 The density of the material (in grams per liter).

D.1.c The manufacturer and repackager of solvents subject to this 

rule shall include the VOC content as supplied, calculated 

pursuant to section B.1.c, expressed in grams per liter, on 

product data sheets, or an equivalent medium.

D.2 Labeling Requirements

D.2.a The manufacturer and repackager of automotive coatings or 

automotive coating components shall include on all containers 

the applicable use category(ies), and the VOC actual for 

coatings and VOC regulatory for coatings, as supplied, 

expressed in grams per liter.

D.2.b The manufacturer and repackager of solvents subject to this 

rule shall include on all containers the VOC content for solvents, 

as supplied, expressed in grams per liter.

D.3 Maintenance of Records.

Records required by this rule shall be retained for a minimum of three 

years and made available for inspection by District personnel upon 

request.

D.4 Record Keeping Requirements.

Any person who uses coatings or solvents subject to this rule shall 

maintain and have available at all times, on site, the following:
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D.4.a A current list of all coatings and solvents used that are subject 

to this rule. This list shall include the following information for 

each coating and solvent:

D.4.a.1 Material name and manufacturer

D.4.a.2 Application method

D.4.a.3 Coating type (as listed in section C.1) and mix ratio 

specific to the coating

D.4.a.4 VOC actual for coatings and VOC regulatory for 

coatings, as applied, or VOC content for solvent.

D.4.a.5 Whether the material is a coating or solvent.

D.4.b Current manufacturer specification sheets, material safety data 

sheets, technical data sheets, or air quality data sheets, which 

list the VOC actual for coatings and VOC regulatory for coatings 

of each ready-to-spray coating (based on the manufacturer’s 

stated mix ratio) and automotive coating components, and VOC 

content of each solvent.

D.4.c Purchase records identifying the coating type (as listed in 

section C.1), name, and volume of coatings and solvents.

D.5 Record Keeping Requirements for Emission Control Systems.

Any person using an emission control system shall maintain daily records 

of key system operating parameters which will demonstrate continuous 

operation and compliance of the emission control system during periods of

VOC emission producing activities. “Key system operating parameters” 

are those parameters necessary to ensure or document compliance with 

section C.3, including, but not limited to, temperatures, pressure drops, 

and air flow rates.

D.6 Record Keeping Requirements for Prohibition of Sale.

Any person claiming an exception specified in section C.5 shall keep a 

detailed log of each automotive coating component and automotive 

coating manufactured, blended, repackaged for sale, supplied, sold, 

offered for sale, or distributed showing:

D.6.a The quantity manufactured, blended, repackaged for sale, 

supplied, sold, offered for sale, or distributed, including size and 

number of containers;
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D.6.b The VOC regulatory for coatings;

D.6.c The VOC actual for coatings;

D.6.d To whom they were supplied, sold, offered for sale, or 

distributed, or for whom they were manufactured, blended, or 

repackaged for sale including the name, address, phone 

number, retail tax license number, and valid district permit 

number; and,

D.6.e The specific exception being utilized under section C.5.

D.1 The provisions of this Rule shall not apply to:

D.1.a A facility which uses a total of less than one (1) gallon of Coating, 

including any VOC-containing materials added to the original 

Coating as supplied by the manufacturer, subject to this Rule, in 

any one day; or

D.1.b Surface Coating operations that emit not more than 3 pounds of 

VOC's per day and not more than 200 pounds of VOC's per 

calendar year.

D.1.c Noncommercial Motor Vehicle and Mobile Equipment Refinishing 

operations performed by any individual at his/her residence for the 

purpose of Finishing or Refinishing that individual's personal 

vehicles.

D.1.d Touch-Up Coatings.

D.1.e Graphic Design Applications.

D.1.f Coating applied using non-refillable hand-held aerosol spray 

containers.

D.1.g Body fillers.

D.1.h Bedliner Coatings.

D.2 The limits set forth in subsection C.1.a.1 and C.1.a.2 shall not apply to:

D.2.a automotive Refinishing operations which emit not more than 3 

pounds of VOC per hour, before add-on controls; or

D.2.b automotive Refinishing operations which emit not more than 15 
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pounds of VOC per day, before add-on controls; or

D.2.c facilities that do not exceed 10 tons per year theoretical Potential 

Emissions. "Theoretical Potential Emissions" is defined as the 

greater of design capacity, or maximum production (based on 8760 

hours/year) before add-on controls.

D.3 For the purposes of claiming an exemption pursuant to subsections D.2.a 

or D.2.b, hourly or daily emissions shall be considered from Date Of 

Adoption of Rule forward.

D.4 Once a facility exceed 3 pounds of VOC per hour, or 15 pounds of VOC 

per day, respectively, it will become and remain subject to the limits even 

if its emissions later fall below the applicability threshold.

D.5 Any facility or Person classified as exempt or claiming to be exempt under 

this section (D), shall meet the record keeping requirements of this Rule 

so as to be able to prove the exemption status.

E. Test Methods Administrative Requirements

The following test methods are incorporated by reference herein, and shall be 

used to test coatings and solvents subject to the provisions of this rule. A source 

is in violation of this rule if any measurement by any of the listed applicable test 

methods exceeds the standards of this rule.

E.1 Methyl Acetate, Acetone, and PCBTF Content.

The quantity of methyl acetate, acetone, and parachlorobenzotrifluoride 

(as specified in section B.1 and the Exempt Compounds found in Rule 101 

Definitions “Volatile Organic Compounds” and “Exempt Compounds” shall 

be determined by using ASTM Method D6133-02: “Standard Test Method 

for Acetone, p-Chlorobenzotrifluoride, Methyl Acetate or t-Butyl Acetate 

Content of Solventborne and Waterborne Paints, Coatings, Resins, and 

Raw Materials by Direct Injection Into a Gas Chromatograph” (February 

2003).

E.2 Acid Content.

Measurement of acid content (as specified in the definition of 

“Pretreatment Coating” found in Rule 101 Definitions) shall be determined 

by using ASTM D1613-03 “Standard Test Method for Acidity in Volatile 

Solvents and Chemical Intermediates Used in Paint, Varnish, Lacquer, 

and Related Products” (October 2003)

E.3 Alternative Test Methods.
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The use of other test methods which are determined to be equivalent or 

better and approved, in writing, by the Executive Officer or Air Pollution 

Control Officer of the District, CARB, and U.S. EPA may be used in place 

of the test methods specified in this rule.

E.4 VOC Content of Coatings or Solvents.

VOC content (as specified in sections B.1, C.1, and C.8.a) shall be 

determined by U.S. EPA Method 24 as set forth in Appendix A of Title 40 

of the Code of Federal Regulations (40 CFR) Part 60, “Determination of 

Volatile Matter Content, Water Content, Density, Volume Solids, and 

Weight Solids of Surface Coatings”.

E.5 Control Efficiency

When either U.S. EPA Method 25, 25A, or 25B is used to determine VOC 

emissions, control device equivalency (as specified in section C.3) shall 

be determined as specified in U.S. EPA’s “Guidelines for Determining 

Capture Efficiency,” (January 9, 1995) and 40 CFR 51, Appendix M, 

Methods 204-204f as applicable.

E.6 Determination of Alternative Compliance.

Alternative compliance (as specified in section C.3) shall be determined by 

U.S. EPA Method 25, 25A, or 25B, Title 40 Code of Federal Regulations, 

Part 60, Appendix A as applicable. A source is in violation if the measured 

VOC emissions, as measured by any of the test methods, exceed the 

standards specified in section C.3.

E.7 Metallic Content.

The metallic content of a coating (as specified in the definition for 

“Metallic/Iridescent Color Coating” found in Rule 101 Definitions shall be 

determined by South Coast Air Quality Management District Method 318-

95, “Determination of Weight Percent Elemental Metal in Coatings by Xray” (July 1996).

E.8 Exempt Compound Content.

Exempt compound content, other than as determined pursuant to section 

E.1, (as specified in the definition for “Volatile Organic Compounds” found 

in Rule 101 Definitions for exempt compounds and section B.1) shall be 

determined by using CARB Method 432, “Determination of 

Dichloromethane and 1,1,1-Trichloroethane in Paints and Coatings” 

(September 12, 1998); CARB Method 422, “Determination of Volatile 
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Organic Compounds in Emissions from Stationary Sources” (January 22, 

1987); or South Coast Air Quality Management District (SCAQMD) 

Method 303-91, “Determination of Exempt Compounds” (February 1993).

E.9 Transfer Efficiency.

Spray equipment transfer efficiency (as specified in the definition for 

“Transfer Efficiency” found in Rule 101 Definitions and C.7.e) shall be 

determined by using South Coast Air Quality Management District “Spray 

Equipment Transfer Efficiency Test Procedures for Equipment User” (May 

24, 1989).

E.10 HVLP Equivalency.

Spray equipment HVLP equivalency (as specified in section C.7.d) shall 

be determined by using South Coast Air Quality Management District 

“Guidelines for Demonstrating Equivalency with District Approved Transfer 

Efficient Spray Guns” (September 26, 2002).

E.1 Extreme Performance Coating Petition: 

Any Person seeking to use an Extreme Performance Coating in any 

Coating operation which is subject to the provisions of this Rule shall 

comply with the following requirements:

E.1.a A petition shall be submitted to the Air Pollution Control Officer 

stating the performance requirements, volume of Coating, and VOC 

level which is attainable. The petitioner must also, in a written 

statement, certify that after reasonable inquiry, to their knowledge, 

no other Coating(s) are available which will meet the requirements 

of subsection C.1.a of this Rule and of the specified performance 

requirements for a specific contract.

E1.b If the Air Pollution Control Officer grants written approval, such 

petition will be repeated on an annual basis.

E.1.c If the Air Pollution Control Officer grants written approval, such 

approval shall contain volume and VOC limit conditions.

E.1.d Records must be maintained as in Section F.1.

E.2 Rule 417 Applicability: 

Any Coating, Coating operation, or facility which is exempt from all or a 

portion of the VOC limits of this Rule shall comply with the provisions of 

Rule 417.
Imperial County Air Pollution Control District Rule 427

427-17

F. Construction of Headings Monitoring and Records

Section and subsection headings do not in any manner affect the scope, 

meaning, or intent of the provisions of this Rule.

All Persons subject to this Rule and any Person claiming any exemption under 

subsection D.1 shall comply with the following requirements:

F.1 Maintain and have available during an inspection, a current list of Coating 

in use which provides all of the Coating data necessary to evaluate 

compliance, including the following information separately for both Group I 

and II vehicles , as applicable:

F.1.a Additive, Coating, Catalyst, and Reducer used.

F.1.b Mix ratio of components used

F.1.c VOC content of Coating as applied.

F.2 Maintain records on a daily basis including:

F.2.a Coating and mix ratio of components used in the Coating; and

F.2.b quantity of each Coating applied.

F.2.c Any Person/facility utilizing an add-on emission Control 

Device/system as a means of complying with provisions of this Rule 

shall also maintain records of key system operating and 

maintenance data for the purpose of demonstrating continuous 

compliance during periods of emission producing activities. The 

data shall be recorded in a manner a prescribed by the District.

F.3 The Person shall maintain records on a monthly basis showing the type 

and amount of solvent used for cleanup and surface preparation.

F.4 Such records shall be retained and available for inspection by the Air 

Pollution Control Officer for the previous 24 month period.

G. Severability Test Methods

Each part of this Rule shall be deemed severable, and in the event that any part 

of this Rule is held to be invalid, the remainder of the Rule shall continue in full 

force and effect.

G.1 A violation of the limits contained in this Rule as determined by any one of 
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427-18

these test methods shall constitute a violation of this Rule.

G.2 The following specified test methods shall be used to determine 

compliance with the provisions of this Rule.

G.2.a Analysis of Samples - VOC Determination: 

Samples of Volatile Organic Compounds (less Exempt 

Compounds) as specified in Sections C.1.a.1 to C.1.a.2 shall be 

analyzed as prescribed by EPA Reference Method 24 for VOC 

content (without correction for Exempt Compounds) and ASTM 

Test Method D4457-85, or CARB Method 432 for determination of 

emissions of Exempt Compounds. Perfluorocarbon compounds 

shall be assumed to be absent from a product or process unless a 

manufacturer or facility operator identifies the specific individual 

compounds (from the broad classes of perfluorocarbon 

compounds) and the amount present in the product or process and 

provides a validated test method which can be used to quantify the 

specific compounds.

G.2.b Determination of Emissions: 

Emissions of Volatile Organic Compounds as specified in Sections 

C.1.a.1 or C.1.a.2 shall be measured as prescribed by EPA 

Reference Method 25 for determining VOC emissions and Control 

Device efficiency, in combination with the methods prescribed in 

U.S. EPA document Guidelines for Determining Capture Efficiency, 

dated January 9, 1995.

G.2.c Determination of Transfer Efficiency: 

Transfer Efficiency as required by Section C.2.a.3 shall be 

determined by procedures as prescribed in the SCAQMD document 

"South Coast Air Quality Management District Spray Equipment 

Transfer Efficiency Test Procedure for Equipment User, May 24, 

1998".

G.2.d Determination of Percentage of Metal in Metallic Coatings: 

Determinations shall be made using SCAQMD Method 311-91, 

"Determination of Percent Metal in Metallic Coatings by 

Spectrographic Method", as found in the SCAQMD document 

Laboratory Methods Of Analysis For Enforcement Samples, The 

June 1991 edition.

G.2.e Acidity in volatile Solvents and in Coating Compounds: 
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427-19

Determination of acid strength shall be made using ASTM Test 

method D1613-85.

G.2.f Determination of Exempt Compounds Content: 

Determination of the content of Exempt Compounds in Coating or 

solvents or any diluents shall be by ASTM Test Method D4457-85.