UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION IX AIR DIVISION

Technical Support Document 

for

EPA’s Direct Final Rulemaking

for the

California State Implementation Plan

Santa Barbara County Air Pollution Control District, 

Rule 337, 

Surface Coating of Aerospace Vehicles and Components

Prepared by: Adrianne Borgia

Reviewed by: Andrew Steckel

December 2012
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RULE IDENTIFICATION

Agency: Santa Barbara County Air Pollution Control District 

(SBCAPCD)

SIP-Approved Rule: Rule 337 – Surface Coating of Aircraft or Aerospace 

Vehicles Parts and Products 

Adopted – October 20, 1994

Submitted – January 24, 1995

Approved – February 12, 1996 (61 FR 5288)

Subject of this TSD: Rule 337 - Surface Coating of Aerospace Vehicles and 

Components

Amended – June 21, 2012

Submitted – September 21, 2012

RULE SUMMARY - Rule 337 establishes reactive organic content (ROC) limits and 

workplace standards for industrial sites engaged in the specification, use, application 

and solicitation of coating, stripping and solvents used for coating aerospace vehicles 

and components, including the cleanup of equipment, and the storage and disposal 

of solvents and waste solvent materials associated with these sites. It also describes 

related recordkeeping, reporting, and monitoring requirements. 

Changes from the approved SIP rule include the following:

1. Section A, Applicability: This section was expanded to include those who use 

or solicit surface coating for aircraft with the understanding that this term 

includes those who specify aerospace vehicle and component coatings. 
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2. Section B, Exemptions: Several exemptions have been added which are 

included in Code of Federal Regulations1(CFR) or California Code of 

Regulations (CCR) with the exception of B.14.a which exempts the cleaning 

or stripping of coating overspray from personal protective equipment. This 

exemption was deemed necessary for safe operating procedures.

3. Several new definitions were added in Section C. All definitions are either 

defined in the Control Techniques Guideline (CTG)2, CFR or the district’s 

SIP-approved rules.

4. The ROC limits in Section D are similar to or lower than those in the CTG. 

There are five categories that are not included in the CTG: Barrier Coating, 

Extreme Performance Interior Topcoat, Fastener Sealant, Interior Topcoat and 

Space Vehicle Coating-Other. These limit values are equal to those of other 

districts including San Joaquin Valley Unified Air Pollution Control District 

(SJVUAPCD), Bay Area Air Quality Management District (BAAQMD) and 

South Coast Air Quality Management District (SCAQMD). 

5. Subsections 9, 10 and 11 were added to Section E, Application Equipment. 

These additions allow other application methods if they are approved by the 

Control Officer, California Air Resources Board (CARB) and the EPA; airatomized spray application for contact and specialty contact adhesives and 

other sealant products that meet a viscosity threshold.

6. Section F, General Operating, which is basically a housekeeping section was 

greatly elaborated to include storage requirements for ROC materials and the 

handling of application equipment and spills.

7. The recordkeeping of Section G, now incorporates more detail, different 

durations for compliant and non-compliant materials, recordkeeping of key 

operating parameters for all facilities using emission control equipment and 

detailed recordkeeping for those claiming the exemption for use of less than 

 

1. 40 CFR 63 Subpart GG – National Emission Standards for Aerospace Manufacturing and Rework Facilities

2. CTG for Control of Volatile Organic Compounds (VOC) from Coating at Aerospace Manufacturing and Rework Facilities –

EPA-453/R-97-004, December 1997
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20 gallons of each formulation. The retention of records on site was reduced 

from 3 years to 2 years which is analogous with other aerospace vehicle 

coating rules.

8. Section I was renamed Compliance Provisions and Test Methods and is 

divided and expanded according to test results, such as control device 

efficiency, application transfer efficiency and viscosity rather than by rule 

section as was the previous arrangement. Several more test methods have 

been included.

9. New sections for solvent cleaning (section J), a compliance schedule (section 

K), reporting criteria for permitted facilities (section L) and requirements for 

solvent cleaning machines (section M) were added to rule 337.

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 SBCAPCD regulates an 

area that is classified as maintenance for the 1-hour ozone standard and is in 

attainment for all criteria pollutants, thus, submitted Rule 337 does not have to 

fulfill RACT requirements.40 C.F.R. § 81.305 (2010). EPA’s CTGs titled

Control of Volatile Organic Compound Emissions from Coating Operations at 
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Aerospace Manufacturing and Rework Operations (EPA-453/R-97-004, 

December 1997) (hereinafter “Aerospace CTG”) and Control of Volatile 

Organic Compound Emissions from Solvent Metal Cleaning (EPA-450/R-2-

77-022, November 1977) (hereinafter “Solvent Metal Cleaning CTG”) cover

many of the sources regulated under Rule 337.

3. SIP Relaxation - CAA section 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. 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).

 EPA’s Aerospace CTG.

 EPA’s Solvent Metal Cleaning CTG.

In addition, we reviewed other state and local rules for this source category.

RULE EVALUATION

1. Enforceability – The recordkeeping requirements for coatings and control 

system parameters, test methods and other requirements generally ensure that 

the submitted rule can be enforced. They include records of usage of 

compliant and noncompliant materials, purchase records, records of key 
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operating parameters and records for those claiming an exemption for de 

minimis usage. Therefore, we propose to determine that submitted Rule 337

is sufficiently clear and enforceable.

2. Stringency – The Aerospace CTG contains EPA’s most recent identification 

of national presumptive RACT for this industry. Since SBCAPCD is in 

attainment, it is not required to meet RACT. Nevertheless, the VOC limits in 

amended Rule 337 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. Those categories for which there are no 

analogous CTG categories are comparable to the most stringent limits of 

other district rules. 

Rule 337 also identifies VOC content limits for solvents that are, for the most 

part, addressed by the Aerospace CTG. Section D.3 of the rule allows, as an 

alternative to compliance with these limits, the use of an add-on control 

system with an overall efficiency of at least 85.5% exceeding the 81% of the 

Aerospace 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. 

3. SIP Relaxation - In addition, we believe the submitted rule is more stringent 

than the version previously approved into the SIP, so the submitted rule does 

not relax the SIP and complies with CAA §110(l) and §193.

RULE DEFICIENCIES – We have identified no deficiencies in submitted Rule 337 

sufficient for EPA to propose less than full approval. 

ADDITIONAL RECOMMENDATIONS FOR THE NEXT RULE REVISION – We have 

no further recommendations for this rule.
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EPA ACTION - EPA staff recommends a full approval of Rule 337 pursuant to CAA 

§110(k) (4) and §301(a). 

ADDITIONAL REFERENCES –

1. SBCAPCD Rule 337 – Surface Coating of Aerospace Vehicles and 

Components submitted September 21, 2012

2. Rule 337 – Surface Coating of Aircraft or Aerospace Vehicles Parts and 

Products, as approved into the SIP on February 12, 1996. 

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

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

6. “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.