UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION IX 

Technical Support Document for 

EPA’s Notice of Proposed Rulemaking for 

the 

California State Implementation Plan 

Eastern Kern Air Pollution Control District 

Rule 432, Polyester Resin Operations 

May 4, 2015
EKAPCD Rule 432– Technical Support Document

Rule Identification

Agency: Eastern Kern Air Pollution Control District (EKAPCD or District) 

SIP Approved Rule: none 

Subject of this Technical Support Document (TSD): Rule 432 – Polyester Resin Operations, Adopted 

March 13, 2014, Submitted July 25, 2014. 

Rule Summary -- The purpose of this rule is to reduce volatile organic compounds (VOC) emissions 

from polyester resin operations. The provisions of this rule apply to commercial polyester resin 

operations, industrial polyester resin operations, and organic solvents (use {including cleaning}, 

storage, waste, and disposal {off-site transfer}) associated with polyester resin operations. 

The rule requirements include the following: 

• Comply with specific limits (Table 1) on VOC content for open molding resin and gel coats. 

Table 1 - VOC Content Limits for Open Molding Resin And Gel Coat 

Compliant Materials Weighted Average Monomer

Material Weight Percent Limit

a. General Purpose Resin 

 Marble Resin 10% or 32%, as supplied, with no fillers 

 Solid Surface 17% 

 Tub/Shower Resin 24% or 35%, as supplied, with no fillers 

 Lamination Resin 31% or 35%, as supplied, with no fillers 

b. Tooling Resin 

Atomized (spray) 30% 

Non-atomized 29% 

c. Specialty Resin 

Fire Retardant Resin 38% 

High Strength Materials 40% 

Corrosion Resistant Resin 48% 

d. All Other Resins 35% 

e. Tooling Gel Coat 40% 

f. Pigmented Gel Coat 

White and Off White 30% 

Non-White 37% 

Primer 28% 

g. Clear Gel Coat 

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EKAPCD Rule 432– Technical Support Document

Marble Resin 40% 

Other Resin 44% 

h. Specialty Gel Coat 48% 

• Non-monomer VOC content of each resin and gel coat shall not contain more than 5 percent by 

weight of the resin or gel coat. Resins must contain a vapor suppressant, so that weight loss 

from VOC emissions does not exceed 50 grams per square meter of exposed surface during 

polymerization. 

• Use a closed mold system or install and operate a VOC emission control system with an overall 

capture and control efficiency of at least 90 percent by weight. 

• Only use spray equipment that is airless, air assisted airless, high-volume low-pressure or 

electrostatic; or install and maintain a VOC emission control system with an overall capture and 

control efficiency of at least 90 percent by weight around the coating operations. 

• Store or dispose of uncured polyester resin, solvents, waste solvent cleaning materials, coatings, 

adhesives, catalysts and thinners in self-closing non-absorbent and non-leaking containers. 

• Comply with specific limits (Table 2) for VOC Content for Organic Solvents. 

Table 2 -- VOC Content Limits for Organic Solvents 

Type of Solvent Cleaning Operation

VOC Content Limit Grams of

VOC/liter of material (lb/gal)

a. Product Cleaning During 

Manufacturing Process or Surface 

Preparation for Coating Application 

25 (0.21) 

b. Repair and Maintenance Cleaning 25 (0.21) 

c. Cleaning of Polyester Resin 

Application Equipment 25 (0.21) 

The rule exempts facilities using less than 20 gallons per day of polyester resin from rule requirements, 

with the exception of recordkeeping requirements needed to document exempt status. The rule exempts 

solvent cleaning provisions for solar cells, laser hardware, scientific instruments, or high precision 

optics. Small jobs may have 10% higher VOC content than Table 1 limits only if applied by certain 

type of hand-held atomized spray gun and total material used does not exceed two gallons a day. 

The rule includes EPA-approved test methods and recordkeeping requirements, including daily records 

of the type and quantity of all resins, gel coats, fillers, catalysts and cleaning materials used, and VOC 

content of all materials used or stored. Records must be kept on-site for five years. 

EPA Evaluation Criteria – The following criteria were used to help evaluate the control requirements 

in Rule 432: 

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EKAPCD Rule 432– Technical Support Document

1. Enforceability – Section 110(a)(2)(A) of the Clean Air Act (CAA) requires that regulations 

submitted to EPA for incorporation into the SIP must be clear and legally enforceable. The 

Bluebook (Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations, 

EPA, May 25, 1988) and the Little Bluebook (Guidance Document for Correcting Common 

VOC & Other Rule Deficiencies, EPA Region 9, August 21, 2001) were used to help 

evaluate compliance with the CAA §110(a)(2)(A) requirement for enforceability. 

2. Stringency – CAA section 172(c)(1) specifies that SIPs for nonattainment areas must include 

RACT for sources of emissions. Section 182(b)(2) specifically provides that for nonattainment 

areas classified as moderate or worse, states must revise their SIP to include RACT for sources 

of VOC emissions covered by a Control Technologies Guideline (CTG) document issued after 

November 15,1990 and prior to the area’s date of attainment. 

3. Non-interference – CAA §110(l) prohibits EPA from approving any SIP revision that would 

interfere with any applicable requirement concerning attainment and reasonable further progress 

(RFP) or any other applicable requirement of the CAA. 

EPA Evaluation

1. Enforceability – Rule 432 includes clear requirements, test methods and recordkeeping 

requirements similar to other SIP-approved rules in nonattainment areas, such as San 

Joaquin Valley Unified Air Pollution Control District Rule 4684 (77 FR 5709), and 

adequately fulfills the CAA enforceability requirements. 

2. Stringency – Eastern Kern County is nonattainment for the federal ozone standard, therefore 

RACT requirements apply. EPA-453/R-08-004, Control Technique Guidelines for 

Fiberglass Boat Manufacturing Material, describes recommended controls for the 

fiberglass boat manufacturing industry, which uses polyester resin. However, the Rule 423 

staff report states that the District does not have any boat manufacturing operations within 

its jurisdiction. There are no other CTGs for non-fiberglass boat manufacturing that would 

apply to this category. 

EKAPCD Rule 432 has similar requirements to San Joaquin Valley Air Pollution Control 

District (SJVAPCD) Rule 4684 Polyester Resin Operations, which was approved into the 

SIP on February 6, 2012 (77 FR 5709) and South Coast Air Quality Management District 

(SCAQMD) Rule 1162 Polyester Resin Operations, which was approved into the SIP on 

July 26, 2011 (76 FR 44493). 

3. Non-interference – This new rule strengthens the SIP so this action will not interfere with the 

District’s ongoing efforts to ensure maintenance of the NAAQS. 

Deficiencies – None identified.

EPA Action -- The submitted Rule 432 will help strengthen the SIP. The rule fulfills the relevant 

CAA section 110 requirements and part D requirements. EPA staff recommends approval of Rule 

432 pursuant to CAA section 110(k)(3) and section 301(a). 

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EKAPCD Rule 432– Technical Support Document

Recommendations – The following recommendations are not currently the basis for rule 

disapproval, but we encourage EKAPCD to consider them the next time the rule is amended:

1. SCAQMD Rule 1162 does not exempt facilities that use less than 20 gallons of polyester resin 

materials per month. Please consider whether this exemption in Rule 432, section III is 

necessary.

References

1. “Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations,” 

2. (a.k.a., Bluebook) EPA OAQPS, May 25, 1988. 

3. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,” (a.k.a., Little 

Bluebook), EPA Region 9, August 21, 2001. 

4. SJVAPCD Rule 4684, Polyester Resin Operations, amended August, 18, 2011, approved 

February 6, 2012 (77 FR 5709). 

5. SCAQMD Rule 1162 Polyester Resin Operations, Amended July 8 2005, approved July 26, 

2011 (76 FR 44493). 

6. Rule 432, Polyester Resin Operations, EKAPCD Staff Report, March 13, 2014. 

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