Imperial County Air Pollution Control District Rule 427

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RULE 427 AUTOMOTIVE REFINISHING OPERATIONS

(Adopted 9/14/99: Revised 02/23/2010)

A. General

A.1 Purpose

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.

B. Definitions

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

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

B.1 VOC Content
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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:

VOC regulatory content = Wv - WW - Wec

Vm - Vw - Vec

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:

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

Vw = volume of water in liters

Vec = volume of exempt compounds in liters

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.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.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.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.
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C.5 Prohibition of Sale or Manufacture

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.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.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 
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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.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.

D. Administrative Requirements

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 
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compounds;

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

compounds; and,

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.
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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:

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, 
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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;

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.

E. Test Methods

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 

Organic Compounds in Emissions from Stationary Sources” (January 22, 
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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).

F. Construction of Headings

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

meaning, or intent of the provisions of this Rule.

G. Severability

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.