UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document 

for

EPA’s Proposed Rulemaking

for the

California State Implementation Plan

San Joaquin Valley Unified Air Pollution Control District, Rule 4605, 

Aerospace Assembly and Component Coating Operations

Prepared by: Adrianne Borgia

Reviewed by: Andrew Steckel

August 2011
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RULE IDENTIFICATION

Agency: San Joaquin Valley Unified Air Pollution Control District 

(SJVUAPCD)

SIP-Approved Rule: Rule 4605 – Aerospace Assembly and Component Coating 

Operations 

Amended – September 20, 2007 

Submitted – March 7, 2008

Approved – January 26, 2010, effective February 25, 2010 

(75 FR 3996)

Subject of this TSD: Rule 4605 - Aerospace Assembly and Component Coating 

Operations

Amended – June 16, 2011 

Submitted – July 28, 2011

RULE SUMMARY - Rule 4605 establishes VOC content limits and workplace standards 

for industrial sites engaged in manufacturing, assembling, coating, masking, bonding, 

paint stripping, surface cleaning, service, and maintenance of aerospace components, the 

cleanup of equipment, and the storage and disposal of solvents and waste solvent materials 

associated with these operations. It also describes related recordkeeping, reporting, and 

monitoring requirements. 

On January 7, 2010, EPA finalized a limited approval/limited disapproval of SJVUAPCD 

Rule 4605. EPA identified the following rule deficiencies which prevented full approval: 

(1) the rule did not include seventeen of the specialty coating limits that were included in 

the relevant Control Technique Guideline (CTG), and (2) for two other specialty coatings 

the rule had higher limits than those provided in the CTG. EPA’s limited approval/limited 

disapproval action started sanctions clocks under section 179 of the Clean Air Act and 40 

CFR 52.31. Unless EPA approves a subsequent SIP revision which corrects the 

deficiencies, offset sanctions will become effective August 25, 2011, and highway 

sanctions will become effective February 25, 2012. 

The primary purpose of the June 2011 rule amendment is to correct deficiencies identified 

by EPA in the January 26, 2010 (75 FR 3996) final rulemaking on the previous version of 

this rule. Changes from the approved SIP rule include the following:

1. New definitions were added in Section 3.0 including those for: Ablative Coating, 

Bearing Coating, Calking and Smoothing Compounds, Chemical Agent-resistant 

Coating (CARC), Electromagnetic Interference (EMI) Coating, Intermediate 

Release Coating, Lacquer, Metalizing Epoxy Coating, Mold Release, Part Marking 

Coating, Rocket Motor Nozzle Coating, Screen Print Ink, Silicone Insulation 

Material, Specialized Function Coating, Thermal Control Coating and Wet 

Fastener Installation Coating.
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2. The following seventeen new products and corresponding VOC content limits 

were added to Table 1 of Section 5.1: Ablative, Bearing Coating, Caulking and 

Smoothing Compounds, Chemical Agent Resistant Coating, Electromagnetic 

Interference Coating, Intermediate Release Coating, Lacquer, Metalized Epoxy 

Coating, Mold Release, Part Marking Coating, Rocket Motor Nozzle Coating, 

Screen Print Ink, Silicone Insulation Material, Specialized Function Coating, 

Thermal Control Coating, Epoxy Polyamide Topcoat and Wet Fastener Installation 

Coating. Relabeled the header “Before January 1, 2013” and included a column for 

VOC limits effective after January 1, 2013. Footnotes were added exempting from 

certain limits coatings designated as “classified” by the Department of Defense and 

coatings used on space vehicles.

3. Lowered the VOC limits for two products in Table 1 of Section 5.1: (1) Fastener 

Sealants and (2) Sealant (Extrudable/Rollable/Brushable), effective January 1, 

2013.

RULE EVALUATION CRITERIA - We primarily used the following criteria to 

evaluate the submitted rule:

1. Enforceability - CAA section 110(a)(2)(A) requires that regulations submitted to 

EPA for approval into a SIP must be clear and legally enforceable.

2. Rule Stringency – CAA section 172(c)(1) requires nonattainment areas to 

implement all reasonably available control measures (RACM), including such 

reductions in emissions from existing sources in the area as may be obtained 

through the adoption, at a minimum, of reasonably available control technology 

(RACT), as expeditiously as practicable. In addition, under CAA section 182(b)(2),

ozone nonattainment areas classified as moderate or above must implement RACT 

for all VOC sources covered by a CTG document and all other major sources of 

VOCs. The SJVUAPCD regulates an ozone nonattainment area that is classified as 

Extreme under both the one-hour ozone and eight-hour ozone standards. 40 C.F.R. 

§ 81.305 (2010).1EPA’s CTG titled Control of Volatile Organic Compound 

Emissions from Coating Operations at Aerospace Manufacturing and Rework

Operations (EPA-453/R-97-004, December 1997) (hereinafter “Aerospace CTG”) 

covers many of the sources regulated under Rule 4605. In addition, EPA’s CTG

titled Control of VOC Emissions from Solvent Metal Cleaning (EPA-450/2-77-022, 

November 1977) (hereinafter “Solvent Metal Cleaning CTG”) covers certain

solvents regulated under Rule 4605. Therefore, submitted Rule 4605 must fulfill 

RACT requirements for VOCs.

3. SIP Revisions - CAA section 110(l) prohibits EPA from approving any SIP 

revision that would interfere with any applicable requirement concerning attainment 

 

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SJVUAPCD also regulates a nonattainment area under the 2006 24-Hour PM2.5 National Ambient Air 

Quality Standard (NAAQS) (40 C.F.R. § 81.305 (2010)). By December 14, 2012, California must submit a 

revision to the State Implementation Plan (SIP) for this nonattainment area that provides for, among other 

things, implementation of all RACM as expeditiously as practicable (CAA § 172(a)(2)(A), (b) & (c)(1), 74 

FR 58689 (Nov. 13, 2009)). EPA will take action on this RACM demonstration in a separate rulemaking.
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and reasonable further progress (RFP) or any other applicable requirement of the 

CAA. In addition, CAA section 193 prohibits the modification of any SIP-approved 

control requirement in effect before November 15, 1990, in a nonattainment area.

In applying these criteria to the submitted rule, we referred to the following guidance and 

policy documents:

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

"Blue Book"), US EPA, OAQPS (May 25, 1988).

Guidance Document for Correcting Common VOC and Other Rule Deficiencies, 

EPA Region IX (August 21, 2001, the “Little Bluebook”).

State Implementation Plans; General Preamble for the Implementation of Title I of 

the Clean Air Act Amendments of 1990, 57 FR 13498 (April 16, 1992); 57 FR 

18070 (April 28, 1992).

Final Rule To Implement the 8-Hour Ozone NAAQS – Phase 2, 70 FR 71612 (Nov. 

25, 2005).

EPA’s Aerospace CTG.

EPA’s Solvent Metal Cleaning CTG.

In addition, we reviewed SJVUAPCD’s 2009 RACT SIP Demonstration (April 16, 2009), 

as well as other state and local rules for this source category.

RULE EVALUATION

Enforceability – The recordkeeping requirements for coatings and control system 

parameters, test methods and other requirements generally ensure that the submitted rule 

can be enforced. Therefore, we propose to determine that submitted Rule 4605 is 

sufficiently clear and enforceable.

Stringency – The Aerospace CTG contains EPA’s most recent identification of national 

presumptive RACT for this industry. The VOC limits in amended Rule 4605 are as or 

more stringent than the VOC limits in this CTG, and we are not aware of significantly 

more stringent requirements in other analogous regulations. 

Rule 4605 also identifies VOC content limits for solvents that are not addressed by the 

Aerospace CTG. Section 5.6 of the rule allows, as an alternative to compliance with these 

limits, the use of a control system with efficiencies of at least 90% capture and 95% 

control. These efficiencies exceed those of the Solvent Metal Cleaning CTG. In addition, 

compliance through use of such a control system must not result in emissions greater than 

the VOC emissions that would have resulted if materials in compliance with the applicable 

VOC limits had been used. 

Based on this and on information provided in SJVUAPCD’s 2009 RACT SIP analysis

regarding other local and national rules and guidance, we believe that this rule fulfills 

CAA RACT requirements.
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SIP Revisions - Because the seventeen coating categories were added and VOC limits for 

two categories were lowered, the submitted rule is more stringent than the version 

previously approved into the SIP. We therefore propose to determine that our approval of 

the submittal would comply with CAA sections 110(l) and 193 because the submitted SIP 

revision: (1) is more stringent than the rule previously approved into the SIP, (2) will insure 

equivalent or greater emission reductions of VOCs, and (3) will not interfere with the ongoing process for ensuring that requirements for RFP and attainment of the NAAQS are 

met.

RULE DEFICIENCIES – We have identified no deficiencies in submitted Rule 4605 

sufficient for EPA to propose less than full approval. As a result, we believe relief from 

sanctions should be provided as quickly as possible. 

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION - The 

following recommendations are not currently the basis for rule disapproval, but we 

encourage SJVUAPCD to consider them the next time the rule is amended:

1. Please consider making the following editorial changes in Section 3.0 to provide 

clear and complete definitions:

a. For consistency with subsection 3.10, refer to Rule 1020 (Definitions) for 

the definition of ARB in subsection 3.11.

b. Remove “a” in the beginning of the definition of “Caulking and Smoothing 

Compounds” in subsection 3.16 as this definition is for the plural 

“materials”.

c. Revise subsection 3.30 to define Wire Coating which is an application for 

both electrical and electronic wire and is consistent with the category in 

Table 1 of Section 5.0. 

d. In subsection 3.31, please correct the statement so that “the electrostatic 

applications are operated at a minimum 60 kV voltage. 

e. For consistency with the definition in the CTG, please change “component” 

to “components” in the definition of Non-structural Adhesive in subsection 

3.55.

f. For thoroughness, please add definitions for the following terms used in the 

rule: Epoxy Polyamide Coating, Electrical Radiation Coating, Electrostatic 

Discharge Protection, Wire Coating (unless change noted in “c”) and PreBonding Etching Wire Coating.

2. For consistency with the CTG exemptions, consider adding touch-up operations to 

Section 4.0.

3. For consistency and completeness please consider making the following changes 

to Table 1 in Section 5.0: 

a. The staff report indicates that this rule applies to sprayable sealant but only 

“extrudable/rollable/brushable” sealant is indicated in item 35. Please add a 

category for sprayable sealant in Table 1 or remove this category from the 

staff report.

b. For consistency with the definition and with the CTG, please revise the 

category in item 43 as “Epoxy Polyamide Topcoat”.
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c. Consider expanding sub-item “a” of item 47 to be “Electrical and

Electronic” as it is likely both types of wiring will require coating.

d. The District has noted that the emission inventory for the source category 

of Aerospace Assembly and Component Coating Operations is 0.02 tons 

per day. Nevertheless, there are three instances where other districts have 

considerably lower VOC limits than SJVAPCD’s rule 4605. Consider 

adopting the lower VOC limits:

i. High Temperature Coating - SMAQMD’s Rule 456 has a 420 g/l 

limit compared to SJVUAPCD’s 850 g/l.

ii. Rain Erosion Resistant Coating – SMAQMD’s Rule 456 has a 600 

g/l limit and VCAPCD’s Rule 74.13 has a 420 g/l limit compared to 

SJVUAPCD’s 800 g/l.

iii. Sealant (Extrudable/Rollable/Brushable) - SCAQMD’s Rule 1124 

has a 280 g/l limit compared to SJVUAPCD’s 600 g/l.

e. We recommend that the District add three specialty coating categories that 

are listed in the CTG but not in the rule: Corrosive Prevention Compound, 

Cryoprotective Coating and Insulation Covering. The lack of these limits is 

not a deficiency that interferes with rule approval because the District has 

confirmed both that these specialty coatings are not in use at this time, and 

that the more stringent general category limit would be applied to any 

source which uses these specialty coatings. 2

4. In section 6.0, per the Little Bluebook (page 13), references to EPA-approved state 

or local (i.e. district) methods should include the full title but may or may not 

specify the date of the version:

a. In Subsection 6.2.1, provide the title for ARB Method 432, “Determination 

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

(EPA approved date is September 12, 1989)

b. In Subsection 6.2.2, correct the title for ASTM Method D1613 to (Standard 

Test Method....)

c. In Subsection 6.2.6, provide the title for ARB Method 422, “Determination 

of Volatile Organic Compounds in Emissions from Stationary Sources.”

(EPA approved date is September 12, 1990). 

EPA ACTION - The submitted changes to Rule 4605 adequately correct deficiencies 

identified by the limited disapproval on the previous version of this rule and otherwise 

fulfill the relevant CAA criteria for the reasons discussed above. As a result, EPA staff 

recommends a full approval of Rule 4605 pursuant to CAA section 110(k)(3). 

 

2 Email from Samir Sheikh (SJVUAPCD) to Andrew Steckel (EPA) dated August 9, 2011.
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ADDITIONAL REFERENCES –

1. SJVUAPCD Rule 4605, Aerospace Assembly and Component Coating Operations, 

as submitted on July 28, 2011.

2. SJVUAPCD Rule 4605, Aerospace Assembly and Component Coating Operations, 

as approved into the SIP on March 7, 2008. 

3. “Control of Volatile Organic Compound Emissions from Coating Operations at 

Aerospace Manufacturing and Rework Operations,” EPA-453/R-97-004, 

December 1997. 

http://www.epa.gov/ttn/naaqs/ozone/ctg_act/199712_voc_epa453_r-97-

004_aerospace_rework.pdf

4. “Control of Volatile Organic Emissions from Solvent Metal Cleaning,” EPA450/2-77-022, November 1977.

http://www.epa.gov/ttn/naaqs/ozone/ctg_act/197711_voc_epa450_2-77-

022_solvent_metal_cleaning.pdf

5. “Reasonably Available Control Technology (RACT) Demonstration for Ozone 

State Implementation Plans (SIP)” SJVUAPCD, April 16, 2009.

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

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

7. “Guidance Document for Correcting Common VOC & Other Rule Deficiencies,” 

(a.k.a., Little Bluebook), EPA Region 9, August 21, 2001.

http://www.epa.gov/Region09/air/sips/littlebluebook2001.