RACT CERTIFICATION OF RULE 348-2021-06-23.PDF

Executive Summary
of the Report to the Board of Supervisors
Prepared by the Maricopa County Air Quality Department
Board Hearing Date: June 23, 2021
Case Number/Title: Rule 348 (Aerospace Manufacturing and Rework
Operations) RACT Certification
Agenda Item: (Pending)
Supervisor Districts: All Districts
The Maricopa County Air Quality Department (MCAQD) complied with all statutory and county
policies throughout this certification process. Per the Enhanced Regulatory Outreach Program
(EROP) Policy: “In addition to the required staff report, an executive summary of the report
including an overview of stakeholder input and staff responses will be provided to the Board of
Supervisors at least one week prior to any Board of Supervisors’ public hearing.”
Overview of the Report to the Board of Supervisors:
Maricopa County is currently classified as a moderate nonattainment area by the U.S. Environmental
Agency (EPA) with respect to the 2008 8-hour National Ambient Air Quality Standard (NAAQS) for
Ozone. As such, Maricopa County is required to implement reasonably available control technology
(RACT) for all major sources of volatile organic compounds (VOC) and for each VOC source category
for which the EPA has issued a Control Technique Guideline (CTG). In 2017, a State Implementation
Plan Revision for the Maricopa County Air Quality Department Ozone Rules was submitted to the
EPA by the Arizona Department of Environmental Quality, which included a negative declaration for
the CTG source category of aerospace coating.
After the EPA requested additional information, the MCAQD reevaluated the source category and
determined that there are facilities in Maricopa County where emissions from aerospace coating
operations exceed the emissions threshold in the Aerospace CTG. As a result, the EPA disapproved
MCAQD’s negative declaration for aerospace coating and required the MCAQD to evaluate Rule 348
to determine if it represents RACT for the 2008 8-hour Ozone NAAQS. The MCAQD evaluated Rule
348 and determined that it is consistent with the Aerospace CTG and is generally consistent with
several other aerospace coating rules recently approved as RACT and, therefore, meets RACT for the
2008 8-hour Ozone NAAQS and no changes to the current version of Rule 348 are required. The
MCAQD will continue with the version approved on September 25, 2013.
Overview of Stakeholder Input and Staff Responses:
The RACT Certification of Rule 348 was made available to the public for a 30-day comment period
beginning on April 7, 2021. As of April 29, 2021, the MCAQD has not received any comments on
the RACT Certification.
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Report to the Board of Supervisors
Prepared by the Maricopa County Air Quality Department
Board of Health Meeting Date: N/A
Board Hearing Date: June 23, 2021
Case Number/Title: Rule 348 (Aerospace Manufacturing and Rework Operations)
RACT Certification
Agenda Item: (Pending)
Supervisor Districts: All Districts
Applicant: Staff
Request: Approve certification of Maricopa County Air Pollution
Control Regulation III - Rule 348 (Aerospace Manufacturing
and Rework Operations) as meeting the Clean Air Act,
Section 182 Reasonably Available Control Technology
(RACT) requirements for the 2008 8-hour Ozone National
Ambient Air Quality Standard (NAAQS) as it is currently
written and the proposed submission of this RACT
Certification to the U.S. Environmental Protection Agency
(EPA). The MCAQD is not proposing any changes to Rule
348.
Maricopa County is currently classified as a moderate
nonattainment area by the EPA with respect to the 2008 8-
hour NAAQS for Ozone. As such, Maricopa County is
required to implement RACT for all major sources of volatile
organic compounds (VOC) and for each VOC source
category for which the EPA has issued a Control Technique
Guideline (CTG). In 2017, a State Implementation Plan
Revision for the Maricopa County Air Quality Department
Ozone Rules was submitted to the EPA by the Arizona
Department of Environmental Quality, which included a
negative declaration for the CTG source category of
aerospace coating.
After the EPA requested additional information, the
MCAQD reevaluated the source category and determined
that there are facilities in Maricopa County where emissions
from aerospace coating operations exceed the emissions
threshold in the Aerospace CTG. As a result, the EPA
disapproved MCAQD’s negative declaration for aerospace
coating and required the MCAQD to evaluate Rule 348 to
determine if it represents RACT for the 2008 8-hour Ozone
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NAAQS. The MCAQD evaluated Rule 348 and determined
that it is consistent with the Aerospace CTG and is generally
consistent with several other aerospace coating rules recently
approved as RACT and, therefore, meets RACT for the 2008
8-hour Ozone NAAQS and no changes to the current
version of Rule 348 are required. The MCAQD will continue
with the version approved on September 25, 2013.
Support/Opposition: As of April 29, 2021, the MCAQD has not received any
comments on the RACT Certification.
Staff
Recommendation: Approve
Board of Health
Recommendation: As no changes to the rule were proposed this rule was not
presented to the Board of Health.
Additional Comments: The RACT Certification of Rule 348 was made available to
the public for a 30-day comment period beginning on April 7,
2021.
A newspaper notice of the Board of Supervisors public
hearing will be published in the Arizona Business Gazette on
May 20, 2021 and May 27, 2021. This RACT Certification will
be submitted to the EPA upon approval by the Board of
Supervisors.
Presented By: Philip A. McNeely, R.G., Director
Prepared By: Planning and Analysis Division
Attachments: Proposed RACT Certification for Rule 348
Copies of all written and electronic Stakeholder input
Rule 348
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Maricopa County Air Quality Department
Phone: 602.506.6010
Fax: 602.506.6985
Maricopa.gov/AQ
CleanAirMakeMore.com
MARICOPA COUNTY REASONABLY AVAILABLE CONTROL
TECHNOLOGY (RACT) CERTIFICATION
May 2021
Reasonably Available Control Technology (RACT) Certification for Volatile
Organic Compound (VOC) Emissions from Aerospace Manufacturing and
Rework Operations in Maricopa County
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TABLE OF CONTENTS
SECTION 1: INTRODUCTION
1.1 Purpose
1.2 Regulatory Background
1.3 RACT Analysis
SECTION 2: COMPLETENESS CRITERIA
2.1 Administrative Materials
2.2 Technical Support
APPENDICES
Appendix 1: Notice of Availability and Notice of Proposed RACT Certification
Appendix 2: Notice of Public Hearing
Appendix 3: Board of Supervisors’ Approval
Appendix 4: Public Comments
Appendix 5: Rule 348 (Adopted September 25, 2013)
Appendix 6: Relevant Arizona Revised Statutes
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Return to Table of Contents
SECTION 1: INTRODUCTION
1.1 Purpose:
This reasonably available control technology (RACT) certification is being submitted to the
U.S. Environmental Protection Agency (EPA) to certify that Maricopa County Air Quality
Department’s (MCAQD) Rule 348 (Aerospace Manufacturing and Rework Operations)
meets RACT for aerospace operations.
1.2 Regulatory Background: Return to Table of Contents
On March 12, 2008, the EPA revised the National Ambient Air Quality Standard (NAAQS)
for ozone. On May 21, 2012, the EPA designated Maricopa County as a nonattainment area
with respect to the 2008 ozone NAAQS. The Maricopa County nonattainment area was
originally classified as marginal nonattainment but was reclassified as a moderate
nonattainment area on May 4, 2016. As a result of this reclassification, Maricopa County was
required to implement RACT for all major sources of volatile organic compounds (VOC)
and for each VOC source category for which the EPA has issued a Control Technique
Guideline (CTG).
On December 19, 2016, on behalf of the MCAQD, the Arizona Department of
Environmental Quality (ADEQ) submitted a State Implementation Plan (SIP) Revision for
the Maricopa County Air Quality Department Ozone Rules Contained in the Arizona SIP.
According to EPA, this submittal did not satisfactorily address the public notice
requirements for the RACT SIP and negative declarations that were included in the
submittal. The MCAQD subsequently satisfied the public notice requirements and on June
16, 2017 submitted a revised SIP submittal to the ADEQ. ADEQ submitted the revised SIP
submittal to the EPA on June 22, 2017.
The revised submittal included a negative declaration for aerospace operations because the
MCAQD originally determined that there were no aerospace manufacturing operations in
Maricopa County that exceeded the applicability threshold recommended in the Aerospace
CTG. In June of 2017, EPA requested additional information regarding aerospace
manufacturing and rework operations in Maricopa County. Following this request, the
MCAQD reevaluated the source category and determined that there are two facilities in
Maricopa County where emissions from aerospace manufacturing and rework operations
exceed 25 tons per year. These facilities were not identified in the initial evaluation because
the majority of the emissions come from solvent cleaning and the application of adhesives
(which are part of an aerospace manufacturing and rework operation), and these processes
were not considered in the initial evaluation.
As a result of this information, the EPA proposed a disapproval of MCAQD’s negative
declaration for aerospace operations on September 18, 2020 (85 FR 58310) and finalized the
disapproval on January 7, 2021. As a result of this disapproval, the MCAQD was required to
evaluate Rule 348 to determine if it represents RACT for the 2008 Ozone Standard.
1.3 RACT Analysis: Return to Table of Contents
Rule 348 (Aerospace Manufacturing and Rework Operations) was adopted on April 7, 1999
to fulfill the RACT fix-up requirements that were imposed on Maricopa County when
Congress enacted the Clean Air Act Amendments of 1990. Rule 348 was submitted to the
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EPA and approved into the Arizona SIP on September 20, 1999. In their evaluation, EPA
determined that Rule 348 was consistent with the CTG for Control of Volatile Organic
Compound Emissions from Coating Operations at Aerospace and Manufacturing Rework
Operations (EPA-453/R-97-004, December 1997). Rule 348 was later revised on September
25, 2013 to update the definition of a volatile organic compound (VOC).
The MCAQD has evaluated Rule 348 and determined that it is consistent with the
Aerospace CTG and is generally consistent with several other aerospace rules recently
approved as RACT and, therefore, meets RACT for the 2008 ozone NAAQS.
The MCAQD identified two rules that are consistent with the Aerospace CTG that were
recently approved by EPA as RACT for the 2008 ozone NAAQS:
 326 Indiana Administrative Code (IAC) 8-21 (adopted 10/13/2011) was approved as
RACT for the 2008 ozone NAAQS on 2/13/2019 (84 FR 3711).
 30 Texas Administrative Code (TAC) 115.420-429 (amended 625/2015) was
approved as RACT for the 2008 ozone NAAQS on 4/30/2019 (84 FR 18145).
The VOC limits in the Indiana and Texas rules are consistent with those in MCAQD’s Rule
348 as well as the Aerospace CTG (see Table 1). In some cases, the VOC limits in Rule 348
are actually more stringent than those in the Indiana and Texas rules.
The MCAQD also identified two recently SIP-approved rules in California for further
comparison:
 Eastern Kern Air Pollution Control District (EKAPCD) Rule 410.8 (adopted
3/13/2014) was approved into the California SIP on 5/17/2016 and is currently
being reviewed for the 2008 ozone NAAQS RACT requirements.
 Mojave Desert Air Quality Management District (MDAQMD) Rule 1118 (adopted
10/26/2015) was approved as RACT for the 2008 ozone NAAQS on 6/21/2018 (82
FR 28240).
The VOC limits in Rule 348 are largely consistent with those in the Aerospace CTG and the
California rules, with the exception of the coating categories documented below. There are
13 coating categories in MCAQD’s Rule 348 that have more stringent VOC limits than
those in one or both of the California rules. There are 16 coating categories where one or
both of the California rules have more stringent VOC limits than Rule 348. The MCAQD
conducted an analysis of data obtained through surveys and/or recent inspections of the
county’s five largest aerospace coating sources with provisions from Rule 348 in their
permits to determine if any of the companies are using coatings in the 16 coating categories
where California rules have more stringent limits and the VOC content of the coatings they
are using in those categories. The MCAQD determined that these sources only use a few of
these coatings and of those used, the majority were observed to have VOC contents that are
lower than the California rules’. Based on the results of our analysis, the total VOC
emissions from categories where California rules which have more stringent limits were
found to be less than 0.5% of each facility’s total VOC emissions.
Outside of California, the MCAQD did not find any rules approved as RACT that were
more stringent than the Aerospace CTG and the aerospace maximum achievable control
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technology (MACT) standard (60 FR 45948, 9/1/1995). Based on these findings, the
MCAQD determined that the requirements in Rule 348 are still the presumptive RACT
standard for aerospace coating and cleaning operations in Maricopa County.
The table below demonstrates that the VOC limits in Rule 348 are consistent with – or, in
some cases, lower than - the VOC limits recommended in the CTG/MACT for Aerospace
Manufacturing and Rework Operations. The table also compares these VOC limits to those
in the Indiana, Texas, and California rules. All VOC limits are displayed as grams per liter
and check marks (✓) indicate where limits are consistent with those in MCAQD’s Rule 348.
Table 1: Comparison of VOC Limits for RACT Analysis
Eastern Mojave
MCAQD CTG/
Coating Type Indiana Texas Kern Desert
Rule 348 MACT
(CA) (CA)
All Primers (except Specialty or General
350 ✓ ✓ ✓ ✓ ✓
Aviation Rework Facility Primers)
All Topcoats (except Specialty or
General Aviation Rework Facility 420 ✓ ✓ ✓ ✓ 340
Topcoats)
General Aviation Rework Facility No
540 ✓ ✓ 350 350
Primers Limit
General Aviation Rework Facility No
540 ✓ ✓ 420 340
Topcoats Limit
Ablative Coating 600 ✓ ✓ ✓ ✓ ✓
Adhesion Promoter 890 ✓ ✓ ✓ 850 850
Adhesive Bonding Primers: Cured at
850 ✓ ✓ ✓ 805 805
250°F or below
Adhesive Bonding Primers: Cured above
1030 ✓ ✓ ✓ 805 805
250°F
Adhesives: Commercial Interior 760 ✓ ✓ ✓ ✓ ✓
Adhesives: Cyanoacrylate 1,020 ✓ ✓ ✓ ✓ ✓
Adhesives: Fuel Tank 620 ✓ ✓ ✓ ✓ ✓
Adhesives: Nonstructural 360 ✓ ✓ ✓ 250 250
Adhesives: Rocket Motor Bonding 890 ✓ ✓ ✓ ✓ ✓
Adhesives: Rubber-based 850 ✓ ✓ ✓ ✓ ✓
Adhesives: Structural Autoclavable 60 ✓ ✓ ✓ 50 50
Adhesives: Structural Nonautoclavable 850 ✓ ✓ ✓ ✓ 700
Antichafe Coating 660 ✓ ✓ ✓ 600 420
Bearing Coating Compounds 620 ✓ ✓ ✓ ✓ ✓
Caulking and Smoothing Compounds 850 ✓ ✓ ✓ ✓ ✓
Chemical Agent-Resistant Coating 550 ✓ ✓ ✓ ✓ 500
Clear Coating 720 ✓ ✓ ✓ 520 420
Commercial Exterior Aerodynamic
350 650 650 650 650 650
Structure Primer
Compatible Substrate Primer 350 780 780 780 780 780
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Table 1: Comparison of VOC Limits for RACT Analysis
Eastern Mojave
MCAQD CTG/
Coating Type Indiana Texas Kern Desert
Rule 348 MACT
(CA) (CA)
Corrosion Prevention Compound 710 ✓ ✓ ✓ ✓ ✓
Cryogenic Flexible Primer 350 645 645 645 645 645
Cryoprotective Coating 600 ✓ ✓ ✓ ✓ ✓
Coatings Related to Electromagnetism
and/or Other Radiation Electric or 600 800 800 800 800 800
Radiation-Effect Coating
Electrostatic Discharge and
Electromagnetic Interference (EMI) 800 ✓ ✓ ✓ ✓ ✓
Coating
Elevated Temperature Skydrol Resistant
350 740 740 740 740 740
Commercial Primer
Epoxy Polyamide Topcoat 420 660 660 660 660 660
Fire-Resistant (Interior) Coating 800 ✓ ✓ ✓ 650 - 800 650 - 800
Flexible Primer 350 640 640 640 640 640
Flight-Test Coatings: Missile or Single
420 ✓ ✓ ✓ ✓ ✓
Use Aircraft
Flight-Test Coatings: All Other 840 ✓ ✓ ✓ ✓ ✓
Fuel-Tank Coating 720 ✓ ✓ ✓ 420 - 720 420 - 720
High-Temperature Coating 850 ✓ ✓ ✓ ✓ 720
Insulation Covering 740 ✓ ✓ ✓ ✓ ✓
Intermediate Release Coating 750 ✓ ✓ ✓ ✓ ✓
Lacquer 830 ✓ ✓ ✓ ✓ ✓
Maskant: Bonding Maskant 420 1,230 1,230 1,230 1,230 1,230
Maskant: Critical Use and Line Sealer
420 1,020 1,020 1,020 750 750
Maskant
Maskant: Seal Coat Maskant 420 1,230 1,230 1,230 1,230 1,230
Metallized Epoxy Coating 740 ✓ ✓ ✓ ✓ 700
Mold Release 780 ✓ ✓ ✓ ✓ ✓
Optical Anti-Reflective Coating 750 ✓ ✓ ✓ 700 700
Part Marking Coating 850 ✓ ✓ ✓ ✓ ✓
Pretreatment Coating 780 ✓ ✓ ✓ ✓ ✓
Rain Erosion-Resistant Coating 420 850 850 850 800 600
Not in No
Resin Surface Sealer 695 No Limit 600 ✓
CTG Limit
Rocket Motor Nozzle Coating 660 ✓ ✓ ✓ ✓ ✓
Scale Inhibitor 880 ✓ ✓ ✓ ✓ ✓
Screen Print Ink 840 ✓ ✓ ✓ ✓ ✓
Sealants: Extrudable/Rollable/Brushable
240 280 280 280 280 280
Sealant
Sealants: Sprayable Sealant 600 ✓ ✓ ✓ ✓ ✓
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Table 1: Comparison of VOC Limits for RACT Analysis
Eastern Mojave
MCAQD CTG/
Coating Type Indiana Texas Kern Desert
Rule 348 MACT
(CA) (CA)
Self-priming Topcoat 420 ✓ 420 - 540 ✓ ✓ ✓
Silicone Insulation Material 850 ✓ ✓ ✓ ✓ ✓
Solid Film Lubricant 880 ✓ ✓ ✓ ✓ ✓
Specialized Function Coating 890 ✓ ✓ ✓ ✓ ✓
Temporary Protective Coating 250 320 320 320 ✓ ✓
Thermal Control Coating 800 ✓ ✓ ✓ ✓ ✓
Wet Fastener Installation Coating 675 ✓ ✓ ✓ ✓ ✓
Wing Coating 420 850 ✓ ✓ 750 750
In addition, the MCAQD rule is consistent with the CTG and RACT as demonstrated
below:
 Rule 348, Section 302 allows the use of an emission control system as an alternative
to meeting the VOC limits in Section 301 if the control system has a combined
capture and control efficiency of at least 81% by weight. This is consistent with the
Aerospace CTG and with rules approved as RACT for other ozone nonattainment
areas (30 TAC 115.423, 326 IAC 8-21-6 and MDAQMD Rule 1118).
 Rule 348, Section 305 includes requirements for solvent cleaning operations that are
part of an aerospace coating operation, including hand-wipe cleaning and flush
cleaning. Rule 348, Section 306 includes requirements for cleaning spray guns. These
requirements are consistent with the Aerospace CTG and with rules approved as
RACT for other ozone nonattainment areas (30 TAC 115.422, 326 IAC 8-21-5 and
MDAQMD Rule 1118).
 Rule 348, Section 307 includes VOC containment and disposal requirements (e.g.
housekeeping measures). These requirements are consistent with the Aerospace
CTG and with rules approved as RACT for other ozone nonattainment areas (30
TAC. 115.422, 326 IAC 8-21-4 and MDAQMD Rule 1118).
 Rule 348, Section 308 includes exemptions that are consistent with the CTG and
rules approved as RACT for other ozone nonattainment areas.
 Rule 348, Section 200 contains definitions that are generally consistent with the
Aerospace CTG.
SECTION 2: COMPLETENESS CRITERIA Return to Table of Contents
2.1 Administrative Materials:
2.1(a) A formal letter of submittal from the MCAQD Director or [his] designee,
requesting the EPA approval of the RACT certification.
See RACT certification submission cover letter from Philip A. McNeely, Director of
the MCAQD, included above.
2.1(b) Evidence that the MCAQD has obtained approval of the RACT certification.
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The Maricopa County Board of Supervisors approved the RACT certification of
Rule 348 on [Date].
See Appendix 3 of this document.
2.1(c) Evidence that the MCAQD has the necessary legal authority under State law
to submit the RACT certification.
See Appendix 6 of this document for copies of Arizona Revised Statutes (A.R.S.) §§
49-112, 49-474, and 49-479 which authorize the MCAQD to submit the RACT
certification of Rule 348.
2.1(d) A copy of the actual regulations or documents submitted for RACT
certification.
See Appendix 5 of this document for a copy of Rule 348.
2.1(e) Evidence that the MCAQD followed all the procedural requirements of the
State’s laws and constitution in conducting and completing the
adoption/issuance of the RACT certification.
The MCAQD completed all the following procedural requirements for obtaining
approval of the RACT SIP certification of Rule 348:
(1) Posted a Notice of Proposed RACT Certification on the Maricopa County
Enhanced Regulatory Outreach Program (EROP) website on April 7,
2021 which provided the public at least 30 days to comment on the
proposed RACT certification;
(2) Provided the public at least 30 days to comment on the proposed RACT
certification of Rule 348 submittal prior to the public hearing (BOS Public
Hearing Notice and Newspaper Affidavit);
(3) Obtained approval of the RACT certification of Rule 348 and approval to
submit the certification to the EPA from the Board of Supervisors (Certified
Minutes of BOS Public Hearing [Date]).
See Appendices 1, 2 and 3.
2.1(f) Evidence that public notice was given of the proposed RACT certification
consistent with procedures approved by the EPA, including the date of
publication of such notice.
See Appendix 2 for evidence that the MCAQD gave public notice of the proposed
RACT certification of Rule 348, including the dates of publication of such notices.
2.1(g) Certification that public hearing(s) were held in accordance with the
information provided in the public notice and the State’s laws and
constitution, if applicable and consistent with the public hearing
requirements in 40 CFR 51.102.
See Appendices 2 and 3.
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2.1(h) Compilation of public comments and the MCAQD’s response.
Appendix 4 includes public comments and MCAQD's response to each comment.
2.2 Technical Support: Return to Table of Contents
2.2(a) Identification of all regulated pollutant(s) affected by the RACT certification.
The regulated pollutant affected by this certification is volatile organic compounds
(VOC).
2.2(b) Identification of the locations of affected sources including the EPA
attainment/nonattainment designation of the locations and the status of the
attainment plan for the affected area(s).
Rule 348 is applicable to all areas and sources under the MCAQD’s jurisdiction.
EPA attainment/nonattainment designations for all or parts of Maricopa County are:
1987 PM10 Standard: Serious Nonattainment (June 10, 1996)
2008 Ozone Standard: Moderate Nonattainment (May 4, 2016)
2015 Ozone Standard: Marginal Nonattainment (June 4, 2018)
1971 Carbon Monoxide Standard: Attainment (April 8, 2005)
2008 Lead Standard: Unclassified/Attainment (December 31, 2011)
2010 Nitrogen Oxides Standard: Unclassified/Attainment (January 31, 2012)
2010 Sulfur Dioxide Standard: Unclassified/Attainment (April 19, 2018)
2012 PM2.5 Standard: Unclassified/Attainment (April 15, 2015)
The status of attainment plans for Maricopa County are:
2012 Five Percent Plan: Approved (June 10, 2014)
2017 MAG Ozone Moderate Plan: Partial Approval (July 2, 2020)
2.2(c) Quantification of the changes in plan allowable emissions from the affected
sources; estimates of changes in current actual emissions from affected
sources or, where appropriate, quantification of changes in actual emissions
from affected sources through calculations of the differences between certain
baseline levels and allowable emissions anticipated as a result of the revision.
Not applicable
2.2(d) The MCAQD’s demonstration that the national ambient air quality standards,
prevention of significant deterioration increments, reasonable further progress
demonstration, and visibility, as applicable, are protected if the plan is
approved and implemented.
Not applicable
2.2(e) Modeling information required to support the proposed revision, including
input data, output data, models used, justification of model selections,
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ambient monitoring data used, meteorological data used, justification for use
of offsite data (where used), modes of models used, assumptions, and other
information relevant to the determination of adequacy of the modeling
analysis.
Not applicable
2.2(f) Evidence, where necessary, that emission limitations are based on continuous
emission reduction technology.
Not applicable
2.2(g) Evidence that the plan contains emission limitations, work practice standards
and recordkeeping/reporting requirements, where necessary, to ensure
emission levels.
Not applicable
2.2(h) Compliance/enforcement strategies, including how compliance will be
determined in practice.
Not applicable
2.2(i) Special economic and technological justifications required by any applicable
EPA policies, or an explanation of why such justifications are not necessary.
Not applicable
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Return to Table of Contents
APPENDIX 1:
NOTICE OF AVAILABILITY AND NOTICE OF PROPOSED RACT CERTIFICATION
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Enhanced Regulatory Outreach Program
Maricopa County Air Quality Department
Notice of Proposed RACT Certification of Rule 348:
Aerospace Manufacturing and Rework Operations
The Maricopa County Air Quality Department (MCAQD) is proposing to certify that Rule 348
(Aerospace Manufacturing and Rework Operations) meets the Clean Air Act Section 182 Reasonably
Available Control Technology (RACT) requirements for the 2008 8-hour ozone National Ambient Air
Quality Standard as it is currently written and implemented within Maricopa County. The RACT
Certification for Rule 348 is attached to this document. The MCAQD is not proposing any changes to
Rule 348.
The RACT Certification was posted on the Maricopa County Enhanced Regulatory Outreach Program
(EROP) website on Wednesday, April 7, 2021. Written comments on this RACT Certification may be
submitted through the EROP website at: http://maricopa.gov/FormCenter/Regulatory-Outreach-
17/Citizen-Comments-94. Please provide written comments by Friday, May 7, 2021.
MCAQD will take reasonable measures to provide access to department services to individuals with
limited ability to speak, write, or understand English and/or to those with disabilities. Requests for
language interpretation services or for disability accommodations must be made at least 48 hours in
advance by contacting: 602-506-6443.
MCAQD tomará las medidas necesarias para brindar acceso a los servicios del departamento a
personas que no dominan el idioma inglés y/o personas con discapacidades. Las solicitudes de
servicios de interpretación de otro idioma o adaptaciones para discapacitados deben realizarse con al
menos 48 horas de anticipación comunicándose con: 602-506-6443.
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Return to Table of Contents
APPENDIX 2:
NOTICE OF PUBLIC HEARING
(Pending Publication of Notice of Public Hearing)
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Return to Table of Contents
APPENDIX 3:
BOARD OF SUPERVISORS’ APPROVAL
(Pending Board of Supervisors’ Approval)
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Return to Table of Contents
APPENDIX 4:
PUBLIC COMMENTS
(Pending Public Comments)
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Return to Table of Contents
APPENDIX 5:
Rule 348 (Adopted September 25, 2013)
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Return to Table of Contents
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 348
AEROSPACE MANUFACTURING AND REWORK OPERATIONS
INDEX
SECTION 100 – GENERAL
101 PURPOSE
102 APPLICABILITY
SECTION 200 – DEFINITIONS
201 ABLATIVE COATING
202 ADHESION PROMOTER
203 ADHESIVE BONDING PRIMER
204 AEROSOL COATING
205 AEROSPACE VEHICLE OR COMPONENT
206 AIRCRAFT FLUID SYSTEMS
207 AIRCRAFT TRANSPARENCY
208 ANTICHAFE COATING
209 ANTIQUE AEROSPACE VEHICLE OR COMPONENT
210 AQUEOUS CLEANING SOLVENT
211 BONDING MASKANT
212 CHEMICAL AGENT-RESISTANT COATING (CARC)
213 CHEMICAL MILLING MASKANT
214 CLEANING OPERATION
215 CLEANING SOLVENT
216 CLEAR COATING
217 CLOSED-CYCLE DEPAINTING SYSTEM
218 COATING
219 COATING OPERATION
220 COATING UNIT
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221 COMMERCIAL EXTERIOR AERODYNAMIC STRUCTURE PRIMER
222 COMMERCIAL INTERIOR ADHESIVE
223 COMPATIBLE SUBSTRATE PRIMER
224 CONFINED SPACE
225 CORROSION PREVENTION SYSTEM
226 CRITICAL USE AND LINE SEALER MASKANT
227 CRYOGENIC FLEXIBLE PRIMER
228 CRYOPROTECTIVE COATING
229 CYANOACRYLATE ADHESIVE
230 ELECTRIC OR RADIATION-EFFECT COATING
231 ELECTROSTATIC DISCHARGE AND ELECTROMAGNETIC
INTERFERENCE (EMI) COATING
232 ELEVATED TEMPERATURE SKYDROL RESISTANT COMMERCIAL
PRIMER
233 EMISSION CONTROL SYSTEM (ECS)
234 EPOXY POLYAMIDE TOPCOAT
235 FIRE-RESISTANT (INTERIOR) COATING
236 FLEXIBLE PRIMER
237 FLIGHT TEST COATING
238 FLUSH CLEANING
239 FUEL TANK ADHESIVE
240 FUEL TANK COATING
241 GENERAL AVIATION
242 GENERAL AVIATION REWORK FACILITY
243 GRAMS PER LITER VOC
244 HAND-WIPE CLEANING OPERATION
245 HIGH TEMPERATURE COATING
246 HIGH VOLUME LOW PRESSURE (HVLP) SPRAY EQUIPMENT
247 INSULATION COVERING
248 INTERMEDIATE RELEASE COATING
249 LACQUER
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250 LEAK
251 LIMITED ACCESS SPACE
252 METALIZED EPOXY COATING
253 MOLD RELEASE
254 NONSTRUCTURAL ADHESIVE
255 OPERATING PARAMETER VALUE
256 OPTICAL ANTI-REFLECTION COATING
257 PART MARKING COATING
258 PRETREATMENT COATING
259 PRIMER
260 RADOME
261 RAIN EROSION-RESISTANT COATING
262 RESEARCH AND DEVELOPMENT
263 RESIN SURFACE SEALER
264 ROCKET MOTOR BONDING ADHESIVE
265 ROCKET MOTOR NOZZLE COATING
266 RUBBER-BASED ADHESIVE
267 SCALE INHIBITOR
268 SCREEN PRINT INK
269 SEAL COAT MASKANT
270 SEALANT
271 SELF-PRIMING TOPCOAT
272 SEMI-AQUEOUS CLEANING SOLVENT
273 SILICONE INSULATION MATERIAL
274 SOLID FILM LUBRICANT
275 SOLIDS
276 SPACE VEHICLE
277 SPECIALIZED FUNCTION COATING
278 SPECIALTY COATING
279 SPRAY GUN
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280 STRUCTURAL AUTOCLAVABLE ADHESIVE
281 STRUCTURAL NONAUTOCLAVABLE ADHESIVE
282 SURFACE PREPARATION
283 TEMPORARY PROTECTIVE COATING
284 THERMAL CONTROL COATING
285 TOPCOAT
286 TOUCH-UP AND/OR REPAIR OPERATIONS
287 VOC COMPOSITE PARTIAL VAPOR PRESSURE
288 WATERBORNE (WATER-REDUCIBLE) COATING
289 WET FASTENER INSTALLATION COATING
290 WING COATING
SECTION 300 – STANDARDS
301 LIMITATIONS-VOC EMISSIONS
302 EMISSION CONTROL SYSTEM
303 REQUIREMENTS FOR AIR POLLUTION CONTROL EQUIPMENT
304 APPLICATION EQUIPMENT
305 SOLVENT CLEANING
306 SPRAY GUN CLEANING
307 VOC CONTAINMENT AND DISPOSAL
308 EXEMPTIONS
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE
SECTION 500 – MONITORING AND RECORDS
501 RECORDKEEPING AND REPORTING
502 COMPLIANCE DETERMINATION
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Adopted 04/07/99
Revised 09/25/13
MARICOPA COUNTY
AIR POLLUTION CONTROL REGULATIONS
REGULATION III – CONTROL OF AIR CONTAMINANTS
RULE 348
AEROSPACE MANUFACTURING AND REWORK OPERATIONS
SECTION 100 – GENERAL
101 PURPOSE: To limit the emission of volatile organic compounds (VOCs) from the
manufacture and rework of aerospace vehicles and their components.
102 APPLICABILITY: This rule applies to the manufacture or rework of commercial, civil, or
military aerospace vehicles. This rule does not apply to research and development, quality
control, laboratory testing, electronic parts and assemblies (except for cleaning and coating
of completed assemblies) and to rework operations performed on antique aerospace vehicles
or components or space vehicles.
SECTION 200 – DEFINITIONS: For the purpose of this rule, the following definitions shall
apply, in addition to those definitions found in Rule 100 (General Provisions and Definitions) of
these rules. In the event of any inconsistency between any of the Maricopa County Air Pollution
Control Rules, the definitions in this rule take precedence.
201 ABLATIVE COATING: A coating that chars when exposed to open flame or extreme
temperatures, as would occur during the failure of an engine casing or during aerodynamic
heating. The ablative char surface serves as an insulative barrier, protecting adjacent
components from the heat or open flame.
202 ADHESION PROMOTER: A very thin coating applied to a substrate to promote wetting
and form a chemical bond with the subsequently applied material.
203 ADHESIVE BONDING PRIMER: A primer applied in a thin film to aerospace
components for the purpose of corrosion inhibition and increased adhesive bond strength
by attachment. There are two categories of adhesive bonding primers, primers with a design
cure at 250°F or below and primers with a design cure above 250°F.
204 AEROSOL COATING: A hand-held, pressurized, nonrefillable container that expels an
adhesive or a coating in a finely divided spray when a valve on the container is depressed.
205 AEROSPACE VEHICLE OR COMPONENT: Any fabricated part, processed part,
assembly of parts, or completed unit, with the exception of electronic components, of any
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aircraft, including but not limited to airplanes, helicopters, missiles, rockets, and space
vehicles.
206 AIRCRAFT FLUID SYSTEMS: Those systems that handle hydraulic fluids, fuel, cooling
fluids, or oils.
207 AIRCRAFT TRANSPARENCY: The aircraft windshield, canopy, passenger windows,
lenses and other components which are constructed of transparent materials.
208 ANTICHAFE COATING: A coating applied to areas of moving aerospace components
that may rub during normal operations or installation.
209 ANTIQUE AEROSPACE VEHICLE OR COMPONENT: An antique aircraft, as
defined by 14 CFR Part 45, or components thereof. An antique aerospace vehicle would not
routinely be in commercial or military service in the capacity for which it was designed.
210 AQUEOUS CLEANING SOLVENT: A solvent in which water is at least 80 percent of
the solvent as applied.
211 BONDING MASKANT: A temporary coating used to protect selected areas of aerospace
parts from strong acid or alkaline solutions during processing for bonding.
212 CHEMICAL AGENT-RESISTANT COATING (CARC): An exterior topcoat designed
to withstand exposure to chemical warfare agents or the decontaminates used in these
agents.
213 CHEMICAL MILLING MASKANT: A coating that is applied directly to aluminum
components to protect surface areas when chemical milling the component with a Type I or
II etchant. This does not include bonding maskants, line sealers, and critical use and seal coat
maskants. Additionally, maskants that must be used on an individual part or subassembly
with a combination of Type I or II etchants and any of the above types of maskants (e.g.,
bonding, line sealers, and critical use and seal coat) are not included. Maskants that are
defined as specialty coatings are not included under this definition.
214 CLEANING OPERATION: Any operation that removes dirt or impurities from
aerospace vehicles, components, or coating equipment. This may include spray gun, hand-
wipe, and flush cleaning operations.
215 CLEANING SOLVENT: A liquid material used for hand-wipe, spray gun, or flush
cleaning. This definition excludes solutions that contain VOCs at a concentration less than
0.1% for carcinogenic VOCs or 1.0% for noncarcinogenic VOCs, as determined from
manufacturers’ representations.
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216 CLEAR COATING: A transparent coating usually applied over a colored opaque coating,
metallic substrate, or placard to give improved gloss and protection to the color coat. In
some cases, a clearcoat refers to any transparent coating without regard to substrate.
217 CLOSED-CYCLE DEPAINTING SYSTEM: A dust free, automated process that
removes permanent coating in small sections at a time, and maintains a continuous vacuum
around the area(s) being depainted to capture emissions.
218 COATING: A material that is applied to the surface of an aerospace vehicle or component
to form a decorative or functional solid film, or the solid film itself.
219 COATING OPERATION: Using a spray booth, tank, or other enclosure or any area, such
as a hangar, for applying a single type of coating (e.g., primer); using the same spray booth
for applying another type of coating (e.g., topcoat) constitutes a separate coating operation
for which compliance determinations are performed separately.
220 COATING UNIT: A series of one or more coating applicators and any associated drying
area and/or oven wherein a coating is applied, dried, and/or cured. A coating unit ends at
the point where the coating is dried or cured, or prior to any subsequent application of a
different coating. It is not necessary to have an oven or flashoff area to be included in this
definition.
221 COMMERCIAL EXTERIOR AERODYNAMIC STRUCTURE PRIMER: A primer
used on aerodynamic components and structures that protrude from the fuselage, such as
wings and attached components, control surfaces, horizontal stabilizers, vertical fins, wing-
to-body fairings, antennae, and landing gear and doors, for the purpose of extended
corrosion protection and enhanced adhesion.
222 COMMERCIAL INTERIOR ADHESIVE: Materials used in the bonding of passenger
cabin interior components. These components must meet the FAA fireworthiness
requirements.
223 COMPATIBLE SUBSTRATE PRIMER: Either compatible Epoxy Primer or Adhesive
Primer. Compatible Epoxy Primer is primer that is compatible with the filled elastomeric
coating and is epoxy based. The compatible substrate primer is an epoxy-polyamide primer
used to promote adhesion of elastomeric coatings such as impact-resistant coatings.
Adhesive Primer is a coating that (1) inhibits corrosion and serves as a primer applied to
bare metal surfaces or prior to adhesive application, or (2) is applied to surfaces that can be
expected to contain fuel. Fuel tank coatings are excluded from this category.
224 CONFINED SPACE: A space that (1) is large enough and so configured that an employee
can bodily enter and perform assigned work; (2) is limited or restricted for entry or exit (for
example, fuel tanks, fuel vessels, and other spaces that have limited entry); and (3) is not
suitable for continuous employee occupancy.
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225 CORROSION PREVENTION SYSTEM: A coating system that provides corrosion
protection by displacing water and penetrating mating surfaces, forming a protective barrier
between the metal surface and moisture. Coatings containing oils or waxes are excluded
from this category.
226 CRITICAL USE AND LINE SEALER MASKANT: A temporary coating, not covered
under other maskant categories, used to protect selected areas of aerospace parts from
strong acid or alkaline solutions such as those used in anodizing, plating, chemical milling
and processing of magnesium, titanium, or high strength steel, high precision aluminum
chemical milling of deep cuts, and aluminum chemical milling of complex shapes. Materials
used for repairs or to bridge gaps left by scribing operations (i.e., line sealer) are also
included in this category.
227 CRYOGENIC FLEXIBLE PRIMER: A primer designed to provide corrosion resistance,
flexibility, and adhesion of subsequent coating systems when exposed to loads up to and
surpassing the yield point of the substrate at cryogenic temperatures (-275°F and below).
228 CRYOPROTECTIVE COATING: A coating that insulates cryogenic or subcooled
surfaces to limit propellant boil-off, maintain structural integrity of metallic structures during
ascent or re-entry, and prevent ice formation.
229 CYANOACRYLATE ADHESIVE: A fast-setting, single component adhesive that cures
at room temperature. Also known as "super glue."
230 ELECTRIC OR RADIATION-EFFECT COATING: A coating or coating system
engineered to interact, through absorption or reflection, with specific regions of the
electromagnetic energy spectrum, such as the ultraviolet, visible, infrared, or microwave
regions. Uses include, but are not limited to, lightning strike protection, electromagnetic
pulse (EMP) protection, and radar avoidance. Coatings that have been designated
"classified" by the Department of Defense are exempt.
231 ELECTROSTATIC DISCHARGE AND ELECTROMAGNETIC
INTERFERENCE (EMI) COATING: A coating applied to space vehicles, missiles,
aircraft radomes, and helicopter blades to disperse static energy or reduce electromagnetic
interference.
232 ELEVATED TEMPERATURE SKYDROL RESISTANT COMMERCIAL
PRIMER: A primer applied primarily to commercial aircraft (or commercial aircraft
adapted for military use) that must withstand immersion in phosphate-ester (PE) hydraulic
fluid (Skydrol 500b or equivalent) at the elevated temperature of 150°F for 1,000 hours.
233 EMISSION CONTROL SYSTEM (ECS ): A system, approved in writing by the Control
Officer, designed and operated in accordance with good engineering practice to reduce
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emissions of volatile organic compounds. Such system consists of an emissions collection
subsystem and an emissions processing subsystem.
234 EPOXY POLYAMIDE TOPCOAT: A coating used where harder films are required or in
some areas where engraving is accomplished in camouflage colors.
235 FIRE-RESISTANT (INTERIOR) COATING: A coating applied to the interior cabin
of an airplane that prevents the interior cabin from being easily ignited and from burning
with extreme rapidity.
236 FLEXIBLE PRIMER: A primer that meets flexibility requirements such as those needed
for adhesive bond primed fastener heads or on surfaces expected to contain fuel.
237 FLIGHT TEST COATING: A coating applied to aircraft other than missiles or single-use
aircraft prior to flight testing to protect the aircraft from corrosion and to provide required
marking during flight test evaluation.
238 FLUSH CLEANING: Removal of contaminants such as dirt, grease, oil, and coatings
from an aerospace vehicle or component or coating equipment by passing solvent over, into,
or through the item being cleaned. The solvent simply may be poured into the item being
cleaned and then drained or assisted by air or hydraulic pressure or by pumping. Hand-wipe
cleaning operations where wiping, scrubbing, mopping or other hand action are used are not
included.
239 FUEL TANK ADHESIVE: An adhesive used to bond components exposed to fuel and
must be compatible with fuel tank coatings.
240 FUEL TANK COATING: A coating applied to fuel tank components for the purpose of
corrosion and/or bacterial growth inhibition and to assure sealant adhesion in extreme
environmental conditions.
241 GENERAL AVIATION (GA): The segment of civil aviation that encompasses all facets
of aviation except air carriers, commuters and military. General aviation includes charter and
corporate-executive transportation, instruction, rental, aerial application, aerial observation,
business, pleasure and other special uses.
242 GENERAL AVIATION REWORK FACILITY: Any aerospace facility with the majority
of its revenues resulting from the reconstruction, repair, maintenance, repainting,
conversion, or alteration of general aviation aerospace vehicles or components.
243 GRAMS PER LITER VOC: A weight of VOC per combined volume of VOC and coating
solids, less water and exempt compounds, and can be calculated by the following equation:
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W s  W w  W es
grams per liter =
V s  V w  V es
Where:
Ws = weight of volatile organic compounds in grams
Ww = weight of water in grams
Wes = weight of exempt compounds in grams
Vs = volume of material in liters
Vw = volume of water in liters
Ves = volume of exempt compounds in liters
244 HAND-WIPE CLEANING OPERATION: Removing contaminants such as dirt, grease,
oil, and coatings from an aerospace vehicle or component by physically rubbing it with a
material such as a rag, paper, or cotton swab that has been moistened with a cleaning
solvent. This definition excludes the use of rags or other material used only to dry excess
solvent from a part or product after removal from a vat or any other solvent bath.
245 HIGH TEMPERATURE COATING: A coating designed to withstand temperatures of
more than 350°F.
246 HIGH VOLUME LOW PRESSURE (HVLP) SPRAY EQUIPMENT: Spray
equipment that is used to apply coating by a spray gun that operates at 10.0 psig of
atomizing air pressure or less at the air cap.
247 INSULATION COVERING: Material that is applied to foam insulation to protect the
insulation from mechanical or environmental damage.
248 INTERMEDIATE RELEASE COATING: A thin coating applied beneath topcoats to
assist in removing the topcoat in depainting operations and generally to allow the use of less
hazardous depainting methods.
249 LACQUER: A clear or pigmented coating formulated with a nitrocellulose or synthetic
resin to dry by evaporation without a chemical reaction. Lacquers are resoluble in their
original solvent.
250 LEAK: A liquid that is allowed to seep or drip or to otherwise enter or escape in either of
the following ways:
a. Three or more drops, including misting and clouding; or
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b. A puddle greater than one square inch.
251 LIMITED ACCESS SPACE: Internal surfaces or passages of an aerospace vehicle or
component that cannot be reached without the aid of an airbrush or a spray gun extension
for the application of coatings.
252 METALIZED EPOXY COATING: A coating that contains relatively large quantities of
metallic pigmentation for appearance and/or added protection.
253 MOLD RELEASE: A coating applied to a mold surface to prevent the molded piece from
sticking to the mold as it is removed.
254 NONSTRUCTURAL ADHESIVE: An adhesive that bonds nonload bearing aerospace
components in noncritical applications and is not covered in any other specialty adhesive
categories.
255 OPERATING PARAMETER VALUE: A minimum or maximum value established for a
control equipment or process parameter that, if achieved by itself or in combination with
one or more other operating parameter values, determines that an owner or operator has
complied with an applicable emission limitation.
256 OPTICAL ANTI-REFLECTION COATING: A coating with a low reflectance in the
infrared and visible wavelength ranges that is used for antireflection on or near optical and
laser hardware.
257 PART MARKING COATING: Coatings or inks used to make identifying markings on
materials, components, and/or assemblies. These markings may be either permanent or
temporary.
258 PRETREATMENT COATING: An organic coating that contains at least 0.5 percent
acids by weight and is applied directly to metal surfaces to provide surface etching, corrosion
resistance, adhesion, and ease of stripping.
259 PRIMER: The first layer and any subsequent layers of identically formulated coating
applied to the surface of an aerospace vehicle or component. Primers are typically used for
corrosion prevention, protection from the environment, functional fluid resistance, and
adhesion of subsequent coatings. Primers that are defined as specialty coatings are not
included under this definition.
260 RADOME: The nonmetallic protective housing for electromagnetic transmitters and
receivers (e.g., radar, electronic countermeasures, etc.).
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261 RAIN EROSION-RESISTANT COATING: A coating or coating system used to
protect the leading edges of parts such as flaps, stabilizers, radomes, engine inlet nacelles,
etc. against erosion caused by rain impact during flight.
262 RESEARCH AND DEVELOPMENT: An operation whose primary purpose is for
research and development of new processes and products and that is conducted under the
close supervision of technically trained personnel and is not involved in the manufacture of
final or intermediate products for commercial purposes, except in a de minimis manner.
263 RESIN SURFACE SEALER: A coating designed or intended to seal the pores of high
porosity cast surfaces of aerospace components composed of magnesium, aluminum or their
alloys to prevent corrosion.
264 ROCKET MOTOR BONDING ADHESIVE: An adhesive used in rocket motor
bonding applications.
265 ROCKET MOTOR NOZZLE COATING: A catalyzed epoxy coating system used in
elevated temperature applications on rocket motor nozzles.
266 RUBBER-BASED ADHESIVE: A quick setting contact cement that provides a strong,
yet flexible bond between two mating surfaces that may be of dissimilar materials.
267 SCALE INHIBITOR: A coating that is applied to the surface of a part prior to thermal
processing to inhibit the formation of scale.
268 SCREEN PRINT INK: Inks used in screen printing processes during fabrication of
decorative laminates and decals.
269 SEAL COAT MASKANT: An overcoat applied over a maskant to improve abrasion and
chemical resistance during production operations.
270 SEALANT: A material used to prevent the intrusion of water, fuel, air, or other liquids or
solids from certain areas of aerospace vehicles or components. There are two categories of
sealants: extrudable/rollable/brushable sealants and sprayable sealants.
271 SELF-PRIMING TOPCOAT: A topcoat that is applied directly to an uncoated aerospace
vehicle or component for purposes of corrosion prevention, environmental protection, and
functional fluid resistance. More than one layer of identical coating formulation may be
applied to the vehicle or component. The coating is not subsequently topcoated with any
other product formulation.
272 SEMIAQUEOUS CLEANING SOLVENT: A solvent wherein at least 60% of the
solvent solution as applied must be water.
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273 SILICONE INSULATION MATERIAL: An insulating material applied to exterior
metal surfaces for protection from high temperatures caused by atmospheric friction or
engine exhaust. These materials differ from ablative coatings in that they are not "sacrificial."
274 SOLID FILM LUBRICANT: A very thin coating consisting of a binder system containing
as its chief pigment material one or more of the following: molybdenum, graphite,
polytetrafluoroethylene (PTFE), or other solids that act as a dry lubricant between faying
surfaces.
275 SOLIDS: The nonvolatile portion of the coating that after drying makes up the dry film.
276 SPACE VEHICLE: A man-made device, either manned or unmanned, designed for
operation beyond earth's atmosphere. This definition includes integral equipment such as
models, mock-ups, prototypes, molds, jigs, tooling, hardware jackets, and test coupons. Also
included is auxiliary equipment associated with test, transport, and storage that through
contamination can compromise the space vehicle performance.
277 SPECIALIZED FUNCTION COATING: A coating that fulfills extremely specific
engineering requirements that are limited in application and are characterized by low volume
usage. This category excludes coatings covered in other Specialty Coating categories.
278 SPECIALTY COATING: A coating that, even though it meets the definition of a primer,
topcoat, or self-priming topcoat, has additional performance criteria beyond those of
primers, topcoats, and self-priming topcoats for specific applications. These performance
criteria may include, but are not limited to, temperature or fire resistance, substrate
compatibility, antireflection, temporary protection or marking, sealing, adhesively joining
substrates, or enhanced corrosion protection.
279 SPRAY GUN: A device that atomizes a coating or other material and projects the
particulates or other material onto a substrate.
280 STRUCTURAL AUTOCLAVABLE ADHESIVE: An adhesive used to bond load
carrying aerospace components that is cured by heat and pressure in an autoclave.
281 STRUCTURAL NONAUTOCLAVABLE ADHESIVE: An adhesive cured under
ambient conditions that is used to bond load carrying aerospace components or other critical
functions, such as nonstructural bonding in the proximity of engines.
282 SURFACE PREPARATION: The removal of contaminants from the surface of an
aerospace vehicle or component or the activation or reactivation of the surface in
preparation for the application of a coating.
283 TEMPORARY PROTECTIVE COATING: A coating applied to provide scratch or
corrosion protection during manufacturing, storage, or transportation. Two types include
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peelable protective coatings and alkaline removable coatings. These materials are not
intended to protect against strong acid or alkaline solutions. Coatings that provide this type
of protection from chemical processing are not included in this category.
284 THERMAL CONTROL COATING: A coating formulated with specific thermal
conductive or radiative properties to permit temperature control of the substrate.
285 TOPCOAT: A coating that is applied over a primer on an aerospace vehicle or component
for appearance, identification, camouflage, or protection. Topcoats that are defined as
specialty coatings are not included under this definition.
286 TOUCH-UP AND/OR REPAIR OPERATIONS: That portion of the coating
operation that is the incidental application of coating used to cover minor imperfections in
the coating finish or to achieve complete coverage. This definition includes out-of-sequence
or out-of-cycle coating.
287 VOC COMPOSITE PARTIAL VAPOR PRESSURE: The sum of the partial pressures
of the compounds defined as VOC's and is determined by the following calculation:
n W i
  VP i
PP  i  1 MW i
s W W n W
w  e   i
MW w MW e i  1 MW i
Where:
Wi = Weight of the "i"th VOC compound, grams.
Ww = Weight of water, grams.
We = Weight of non-HAP, non-VOC compound, grams.
MWi = Molecular weight of the "i"th VOC compound, g/g-mole.
MWw = Molecular weight of water, g/g-mole.
MWe = Molecular weight of exempt compound, g/g-mole.
PPc = VOC composite partial pressure at 20°C, mm Hg.
VPi = Vapor pressure of the "i"th VOC compound at 20°C, mm Hg.
288 WATERBORNE (WATER-REDUCIBLE) COATING: A coating which contains more
than 5 percent water by weight as applied in its volatile fraction.
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289 WET FASTENER INSTALLATION COATING: A primer or sealant applied by
dipping, brushing, or daubing to fasteners that are installed before the coating is cured.
290 WING COATING: A corrosion-resistant topcoat that is resilient enough to withstand the
flexing of the wings.
SECTION 300 – STANDARDS
301 LIMITATIONS: VOC EMISSIONS: No person shall apply any surface coating including
any VOC-containing materials added to the original coating supplied by the manufacturer,
which contain VOC in excess of the limits in Tables 1a and 1b, unless the emissions are
controlled in accordance with the provisions of Section 302 of this rule.
Table 1A
PRIMER or TOPCOAT TYPE VOC LIMITS (g/L)
All Primers (except Specialty or General Aviation Rework Facility Primers) 350 g/l
All Topcoats (except Specialty or General Aviation Rework Facility 420 g/l
Topcoats)
General Aviation Rework Facility Primers 540 g/l
General Aviation Rework Facility Topcoats 540 g/l
Table 1B
Type of Specialty Coating VOC Limits (g/L)
Ablative Coating 600
Adhesion Promoter 890
Adhesive Bonding Primers: Cured at 250°F or below 850
Adhesive Bonding Primers: Cured above 250°F 1030
Adhesives: Commercial Interior 760
Adhesives: Cyanoacrylate 1,020
Adhesives: Fuel Tank 620
Adhesives: Nonstructural 360
Adhesives: Rocket Motor Bonding 890
Adhesives: Rubber-based 850
Adhesives: Structural Autoclavable 60
Adhesives: Structural Nonautoclavable 850
Antichafe Coating 660
Bearing Coating Compounds 620
Caulking and Smoothing Compounds 850
Chemical Agent-Resistant Coating 550
Clear Coating 720
Commercial Exterior Aerodynamic Structure Primer 350
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Table 1B
Type of Specialty Coating VOC Limits (g/L)
Compatible Substrate Primer 350
Corrosion Prevention Compound 710
Cryogenic Flexible Primer 350
Cryoprotective Coating 600
Coatings Related to Electromagnetism and/or Other Radiation Electric or 600
Radiation-Effect Coating
Electrostatic Discharge and Electromagnetic Interference (EMI) Coating 800
Elevated Temperature Skydrol Resistant Commercial Primer 350
Epoxy Polyamide Topcoat 420
Fire-Resistant (Interior) Coating 800
Flexible Primer 350
Flight-Test Coatings: Missile or Single Use Aircraft 420
Flight-Test Coatings: All Other 840
Fuel-Tank Coating 720
High-Temperature Coating 850
Insulation Covering 740
Intermediate Release Coating 750
Lacquer 830
Maskant: Bonding Maskant 420
Maskant: Critical Use and Line Sealer Maskant 420
Maskant: Seal Coat Maskant 420
Metallized Epoxy Coating 740
Mold Release 780
Optical Anti-Reflective Coating 750
Part Marking Coating 850
Pretreatment Coating 780
Rain Erosion-Resistant Coating 420
Resin Surface Sealer 695
Rocket Motor Nozzle Coating 660
Scale Inhibitor 880
Screen Print Ink 840
Sealants: Extrudable/Rollable/Brushable Sealant 240
Sealants: Sprayable Sealant 600
Self-priming Topcoat 420
Silicone Insulation Material 850
Solid Film Lubricant 880
Specialized Function Coating 890
Temporary Protective Coating 250
Thermal Control Coating 800
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Table 1B
Type of Specialty Coating VOC Limits (g/L)
Wet Fastener Installation Coating 675
Wing Coating 420
302 EMISSION CONTROL SYSTEM: As an alternative to meeting the applicable coating
VOC limits set forth in Section 301, an operator can comply with this rule by operating an
Emission Control System (ECS) approved by the Control Officer, provided that the control
system has a combined VOC emissions capture and control equipment efficiency of at least
81 percent by weight.
303 REQUIREMENTS FOR AIR POLLUTION CONTROL EQUIPMENT:
303.1 Operation and Maintenance (O&M) Plan Required for ECS:
a. An owner or operator shall provide and maintain (an) O&M Plan(s) for any ECS,
any other emission processing equipment, and any ECS monitoring devices that
are used pursuant to this rule or to an air pollution control permit.
b. The owner or operator shall submit to the Control Officer for approval the
O&M Plans of each ECS and each ECS monitoring device that is used pursuant
to this rule.
c. An owner or operator of a facility that is required to have an O&M Plan
pursuant to this subsection must fully comply with all O&M Plans that the
owner or operator has submitted for approval, but which have not yet been
approved, unless notified otherwise by the Control Officer in writing.
304 APPLICATION EQUIPMENT: A person shall use one or more of the following
application techniques in applying any primer or topcoat to aerospace vehicles or
components: flow/curtain coat; dip coat; roll coating; brush coating; cotton-tipped swab
application; electrodeposition (DIP) coating; high volume low pressure (HVLP) spraying;
electrostatic spray; or other coating application methods that can demonstrate and be
approved by the Control Officer as having at least a 65% transfer efficiency, which is
equivalent to the transfer efficiency of HVLP or electrostatic spray application methods.
305 SOLVENT CLEANING: The following requirements apply to solvent cleaning
operations:
305.1 Hand-Wipe Cleaning: Cleaning solvents used in hand-wipe cleaning operations
shall utilize an aqueous cleaning solvent, or have a VOC composite vapor pressure
less than or equal to 45 millimeters of mercury (mm Hg) at 20°C.
305.2 Flush Cleaning: For cleaning solvents used in the flush cleaning of parts,
assemblies, and coating unit components, the used cleaning solvent (except for semi-
aqueous cleaning solvents) must be emptied into an enclosed container or collection
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system that is kept closed when not in use or captured with wipers, provided they
comply with the VOC handling requirements of Section 307 of this rule.
305.3 Dip Cleaning: Dip cleaning using solvents is subject to the requirements of Rule
331.
306 SPRAY GUN CLEANING: All spray guns must be cleaned by one or more of the
following methods:
306.1 Enclosed spray gun cleaning system, provided that it is kept closed when not in use
and leaks are repaired within 14 days from when the leak is first discovered. If the
leak is not repaired by the 15th day after detection, the solvent shall be removed and
the enclosed cleaner shall be shut down until the leak is repaired or its use is
permanently discontinued;
306.2 Unatomized discharge of solvent into a waste container that is kept closed when not
in use;
306.3 Disassembly of the spray gun and cleaning in a vat that is kept closed when not in
use; or
306.4 Atomized spray into a waste container that is fitted with a device designed to capture
atomized solvent emissions.
307 VOC CONTAINMENT AND DISPOSAL: All fresh and used VOC containing material,
including but not limited to cleaning solvents, coatings, thinners, rags, and their residues,
shall be stored in closed, leak free, legibly labeled containers when not in use. In addition,
the owner or operator must implement handling and transfer procedures to minimize spills
during filling and transferring the cleaning solvent to or from enclosed systems, vats, waste
containers, and other cleaning operation equipment that hold or store fresh or used cleaning
solvents.
308 EXEMPTIONS:
308.1 Coatings: The following coatings types are exempted from the VOC limits set forth
in Tables 1a and 1b in Section 301 of this rule:
a. Touchup coatings;
b. Hand-held aerosol can operations;
c. DOD "classified" coatings;
d. Coating of space vehicles; and
e. Low usage coatings used in separate formulations in volumes of less than 50
gallons per year with a maximum exemption of 200 gallons total for such
formulations applied annually.
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308.2 Application Equipment: The following operations are exempt from the
requirements of Section 304 of this rule:
a. Any situation that normally requires the use of an airbrush or an extension on
the spray gun to properly reach limited access spaces;
b. The application of specialty coatings;
c. The application of coatings that contain fillers that adversely affect atomization
with HVLP spray guns and that the permitting agency has determined cannot be
applied by any of the application methods;
d. The application of coatings that normally have a dried film thickness of less than
0.0013 centimeter (0.0005 in.) and that the permitting agency has determined
cannot be applied by any of the application methods;
e. The use of airbrush application methods for stenciling, lettering, and other
identification markings; and
f. Touch-up and repair operations.
308.3 Solvent Cleaning Operations: The following are exempt from the requirements of
Section 305 of this rule:
a. Cleaning during the manufacture, assembly, installation, maintenance, or testing
of components of breathing oxygen systems that are exposed to the breathing
oxygen;
b. Cleaning during the manufacture, assembly, installation, maintenance, or testing
of parts, subassemblies, or assemblies that are exposed to strong oxidizers or
reducers (e.g., nitrogen tetroxide, liquid oxygen, hydrazine);
c. Cleaning and surface activation prior to adhesive bonding;
d. Cleaning of electronics parts and assemblies containing electronics parts;
e. Cleaning of aircraft and ground support equipment fluid systems that are
exposed to the fluid, including air-to-air heat exchangers and hydraulic fluid
systems;
f. Cleaning of fuel cells, fuel tanks, and confined spaces;
g. Surface cleaning of solar cells, coated optics, and thermal control surfaces;
h. Cleaning during fabrication, assembly, installation, and maintenance of
upholstery, curtains, carpet, and other textile materials used on the interior of the
aircraft;
i. Cleaning of metallic and nonmetallic materials used in honeycomb cores during
the manufacture or maintenance of these cores, and cleaning of the completed
cores used in the manufacture of aerospace vehicles or components;
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j. Cleaning of aircraft transparencies, polycarbonate, or glass substrates;
k. Cleaning and solvent usage associated with research and development, quality
control, or laboratory testing;
l. Cleaning operations using nonflammable liquids conducted within 5 feet of
energized electrical systems. Energized electrical systems means any AC or DC
electrical circuit on an assembled aircraft once electrical power is connected,
including interior passenger and cargo areas, wheel wells and tail sections; and
m. Cleaning operations identified in an Essential Use Waiver which has been
reviewed and approved by the U.S. EPA and the voting parties of the
International Montreal Protocol Committee [sections 604(d)(1) and (g)(2) of the
Act].
308.4 General Exemptions: Cotton-tipped swabs used for very small cleaning operations
and aqueous cleaning solvents are exempt from the requirements of Section 307 of
this rule.
308.5 Small Sources: Sections 301 and 302 of this rule shall not apply to any one facility
from which the total VOC emissions from all operations subject to this rule emit less
than 15 pounds (6.8 kg) per day and less than two tons (1814 kg) per year of VOCs
prior to any controls.
SECTION 400 – ADMINISTRATIVE REQUIREMENTS
401 COMPLIANCE SCHEDULE: All facilities subject to this rule shall meet all applicable
provisions of this rule by October 4, 1999. The intention to use an ECS in accordance with
Section 302 of this rule shall be announced to the Control Officer in writing by July 6, 1999,
and be in use by April 7, 2000.
SECTION 500 – MONITORING AND RECORDS
501 RECORDKEEPING AND REPORTING: Any person subject to this rule shall comply
with the following requirements. Records shall be retained for five years and shall be made
available to the Control Officer upon request.
501.1 Coatings: Each owner or operator using coatings listed in Section 301 of this rule
shall maintain a current list of coatings in use, VOC content as applied and records
of the monthly usage of such materials in pounds per gallon or grams per liter.
501.2 Cleaning Solvents: Each owner or operator shall:
a. Maintain a current list of all aqueous and semi-aqueous hand-wipe cleaning
solvents used with corresponding water contents.
b. Maintain a current list of all vapor pressure compliant hand-wipe cleaning
solvents in use with their respective vapor pressures or, for blended solvents,
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VOC composite vapor pressures and records of the monthly usage of such
cleaning solvents.
c. Maintain a current list of all hand-wipe cleaning processes using cleaning solvents
with a vapor pressure greater than 45 mm Hg and records of the monthly usage
of such cleaning solvents.
501.3 Enclosed Spray Gun Cleaners: Any person using an enclosed spray gun cleaner
shall visually inspect the seals and all other potential sources of leaks at least once per
month while the spray gun cleaner is in operation. Records of these inspections shall
be kept and made available upon request by the Control Officer.
502 COMPLIANCE DETERMINATION: The test methods for those subparts of 40 CFR
Part 60, Appendix A adopted as of July 1, 1998, as listed below, are adopted by reference as
indicated. These adoptions by reference include no future editions or amendments. Copies
of test methods referenced in subsection 502.1 are available at the Maricopa County Air
Quality Department. When more than one test method is permitted for a determination, an
exceedance of the limits established in the rule determined by any of the applicable test
methods constitutes a violation of this rule.
502.1 Test Methods:
a. Coatings: The VOC content of coatings (less water and less non-precursor
organic compounds) as applied shall be determined by manufacturer's supplied
data or Method 24 of 40 CFR part 60, Appendix A. If there is a discrepancy
between the manufacturer's formulation data and the results of the Method 24
analysis, compliance shall be based on the results from the Method 24 analysis.
For waterborne (water-reducible) coatings, only manufacturer's supplied data can
be used to determine the VOC content of each formulation.
b. Control Equipment: Measurements of VOC emissions from control equipment
shall be conducted in accordance with EPA Methods 18, 25, and/or 25A, 40
CFR 60, Appendix A.
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Return to Table of Contents
APPENDIX 6:
RELEVANT ARIZONA REVISED STATUTES
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49-112. County regulation; standards
A. When authorized by law, a county may adopt a rule, ordinance or regulation that is more
stringent than or in addition to a provision of this title or rule adopted by the director or any board
or commission authorized to adopt rules pursuant to this title if all of the following requirements are
met:
1. The rule, ordinance or regulation is necessary to address a peculiar local condition.
2. There is credible evidence that the rule, ordinance or regulation is either:
(a) Necessary to prevent a significant threat to public health or the environment that results from a
peculiar local condition and is technically and economically feasible.
(b) Required under a federal statute or regulation, or authorized pursuant to an intergovernmental
agreement with the federal government to enforce federal statutes or regulations if the county rule,
ordinance or regulation is equivalent to federal statutes or regulations.
3. Any fee or tax adopted under the rule, ordinance or regulation does not exceed the reasonable
costs of the county to issue and administer the permit or plan approval program.
B. When authorized by law, a county may adopt rules, ordinances or regulations in lieu of a state
program that are as stringent as a provision of this title or rule adopted by the director or any board
or commission authorized to adopt rules pursuant to this title if the county demonstrates that the
cost of obtaining permits or other approvals from the county will approximately equal or be less
than the fee or cost of obtaining similar permits or approvals under this title or any rule adopted
pursuant to this title. If the state has not adopted a fee or tax for similar permits or approvals, the
county may adopt a fee when authorized by law in the rule, ordinance or regulation that does not
exceed the reasonable costs of the county to issue and administer that permit or plan approval
program.
C. A county that adopts rules, ordinances or regulations pursuant to subsection B of this section and
that at any time cannot comply with subsection B of this section shall prepare and file a notice of
noncompliance with the director. The county shall post a copy of the notice of noncompliance on
the county's website with a date stamp of the date of posting. If the county does not comply with
subsection B of this section within one year after posting of the notice on the county's website, the
director shall provide written notice to and assert regulatory jurisdiction over those persons and
entities subject to the affected county rules, ordinances or regulations.
D. Except as provided in chapter 3, article 3 of this title, before adopting or enforcing any rule,
ordinance or regulation pursuant to subsection A or B of this section, the county shall comply with
the following requirements:
1. Prepare a notice of proposed rulemaking to include the proposed rule, ordinance or
regulation. This notice shall demonstrate evidence of compliance with subsection A or B of this
section. The notice shall include the name, address and phone number of a person who can answer
questions about the proposed rule, ordinance or regulation and accept any written requests for the
county to conduct an oral proceeding. The county shall post the notice on the county's website with
a date stamp of the date of posting. The county shall publish the availability of the notice of the
proposed rule, ordinance or regulation in a newspaper of general circulation in the county. If there is
no newspaper of general circulation in the county, the county shall publish the notice in a newspaper
of general circulation in an adjoining county. If requested by the public, the county shall make
available a paper copy of the notice at a reasonable cost.
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2. For at least thirty days after the posting of the notice of the proposed rule, ordinance or
regulation, afford persons the opportunity to submit in writing comments, statements, arguments,
data and views on the proposed rule, ordinance or regulation.
3. Respond in writing to the comments submitted pursuant to paragraph 2 of this subsection and
post the county's response on the county's website. If requested by the public, the county shall make
paper copies of its comments available at a reasonable cost.
4. Schedule a public hearing on the proposed rule, ordinance or regulation if a written request for an
oral proceeding is submitted to the county during the thirty-day comment period. The county shall
post the notice of oral proceeding on a proposed rule, ordinance or regulation on the county's
website. The county shall post the notice of oral proceeding at least twenty days before the date of
the oral proceeding. The county shall publish notice of any public hearing required pursuant to this
paragraph in any newspaper as prescribed by this title or county ordinance. The county shall select a
time and location for the public hearing that affords a reasonable opportunity for the public to
participate.
E. A county is not required to comply with subsection D, paragraphs 2, 3 and 4 of this section
before it adopts or enforces a rule, ordinance or regulation if the rule, ordinance or regulation only
incorporates by reference an existing state or federal rule or law that provides greater regulatory
flexibility for regulated parties and otherwise satisfies the requirements prescribed in subsection B of
this section.
F. Until June 30, 1995, a person may file with the clerk of the board of supervisors for that county a
petition challenging a county rule, ordinance or regulation adopted before July 15, 1994 for
compliance with the criteria set forth in subsection A or B of this section. The petition shall contain
the grounds for challenging the specific county rule, ordinance or regulation. Within one year after
the petition is filed, the board of supervisors shall review the challenged rule, ordinance or regulation
and make a written demonstration of compliance with the criteria set forth in subsection A or B of
this section and challenged in the petition. Any rules, ordinances or regulations that have been
challenged and for which the board of supervisors has not made the written demonstration within
one year after the filing of the petition required by this section become unenforceable as of that date.
If a county has already made a written demonstration under section 49-479, subsection C, for a rule,
ordinance or regulation, the person filing the petition shall state the specific grounds in the petition
why that demonstration does not meet the requirements of this section.
G. A rule, ordinance or regulation adopted pursuant to subsection A of this section may not be
invalidated subsequent to its adoption on the grounds that the economic feasibility analysis is
insufficient or inaccurate if a county makes a good faith effort to comply with the economic
feasibility requirement of subsection A, paragraph 2, subdivision (a), of this section and has
explained in the written statement, made public pursuant to subsection D of this section, the
methodology used to satisfy the economic feasibility requirement.
H. This section shall not apply to any rule, ordinance or regulation adopted by a county pursuant to:
1. Title 36 for which the state has similar statutory or rule making authority in this title.
2. Section 49-391.
3. Chapter 3, article 8 of this title.
4. Chapter 4, article 3 of this title and section 49-765.
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5. Nonsubstantive rules relating to the application process that have a de minimis economic effect
on regulated parties.
49-474. County control boards
The board of supervisors of each county may authorize the board of health or health department of
their respective counties in cooperation with the department of environmental quality to:
1. Study the problem of air pollution in the county.
2. Study possible effects on adjoining counties.
3. Cooperate with chambers of commerce, industry, agriculture, public officials and all other
interested persons or organizations.
4. Hold public hearings if in their discretion such action is necessary.
5. The board of supervisors by resolution may establish an air pollution control district.
49-479. Rules; hearing
A. The board of supervisors shall adopt such rules as it determines are necessary and feasible to
control the release into the atmosphere of air contaminants originating within the territorial limits of
the county or multi-county air quality control region in order to control air pollution, which rules,
except as provided in subsection C shall contain standards at least equal to or more restrictive than
those adopted by the director. In fixing such standards, the board or region shall give consideration
but shall not be limited to:
1. The latest scientific knowledge useful in indicating the kind and extent of all identifiable effects on
health and welfare which may be expected from the presence of an air pollution agent, or
combination of agents in the ambient air, in varying quantities.
2. Atmosphere conditions and the types of air pollution agent or agents which, when present in the
atmosphere, may interact with another agent or agents to produce an adverse effect on public health
and welfare.
3. Securing, to the greatest degree practicable, the enjoyment of the natural attractions of the state
and the comfort and convenience of the inhabitants.
B. No rule may be enacted or amended except after the board of supervisors first holds a public
hearing after twenty days' notice of such hearing. The proposed rule, or any proposed amendment
of a rule, shall be made available to the public at the time of notice of such hearing.
C. A county may adopt or amend a rule, emission standard, or standard of performance that is as
stringent or more stringent than a rule, emission standard or standard of performance for similar
sources adopted by the director only if the county complies with the applicable provisions of section
49-112.
D. All rules enacted pursuant to this section shall be made available to the public at a reasonable
charge upon request.
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