SAN DIEGO AIR POLLUTION CONTROL DISTRICT 

RULE 66.1 MISCELLANEOUS SURFACE COATING OPERATIONS AND 

OTHER PROCESSES EMITTING VOLATILE ORGANIC 

COMPOUNDS (Adopted 2/24/10)

(a) APPLICABILITY 

(1) This rule is applicable to all surface coating, solvent cleaning or other 

operations or processes that may result in emissions of VOCs and are not subject to or 

exempt from, the following rules: 

67.0 - Architectural Coatings; 

67.2 - Dry Cleaning Equipment Using Petroleum Based Solvents; 

67.3 - Metal Parts and Products Coating Operations; 

67.4 - Metal Container, Metal Closure and Metal Coil Coating Operations; 

67.5 - Paper, Film and Fabric Coating Operations; 

67.6.1 - Cold Solvent Cleaning and Stripping Operations; 

67.6.2 - Vapor Degreasing Operations; 

67.9 - Aerospace Coating Operations; 

67.10 - Kelp Processing and Bio-Polymer Manufacturing Operations; 

67.11 - Wood Products Coating Operations; 

67.11.1 - Large Coating Operations for Wood Products; 

67.12 - Polyester Resin Operations; 

67.15 - Pharmaceutical and Cosmetic Manufacturing Operations; 

67.16 - Graphic Arts Operations; 

67.18 - Marine Coating Operations; 

67.19 - Coatings and Printing Inks Manufacturing Operations; 

67.20 - Motor Vehicle and Mobile Equipment Refinishing Operations; 

67.21 - Adhesive Materials Application Operations; 

67.24 - Bakery Ovens; 

61.1 through 61.8 – Vapor Recovery Rules; 

68 through 69.4.1 – Rules Regulating Combustion Sources. 

(2) Section (g) of this rule is applicable to any manufacturer, seller or supplier of 

any coating, coating component, solvent cleaning material, or any other VOC containing 

material that is used in an operation that may be subject to this rule.

(b) EXEMPTIONS 

(1) This rule shall not apply to the following: 

(i) Surface coatings, surface preparation or solvent cleaning materials applied 

using hand-held non-refillable aerosol spray containers. 

(ii) Any surface coating operation where 20 gallons or less of surface coatings 

are applied per consecutive 12-month period. To claim applicability of this 

exemption monthly coating usage records shall be maintained on site for three years 

and made available to the District upon request. 

Regulation IV -1- Rule 66.1 
(iii) Any surface coating or other VOC emitting operation where the total VOC 

emissions, excluding emissions from cleaning or surface preparation materials, are 

150 lbs or less per consecutive 12-month period. To claim applicability of this 

exemption all records necessary to calculate VOC emissions shall be maintained on 

site for three years and made available to the District upon request. 

 (iv) The use of pesticides, including insecticides, rodenticides or herbicides. 

(v) Research and development operations or testing for quality control or 

quality assurance purposes. 

(vi) Operations involved in the manufacture of biotechnology pharmaceutical 

and bio-agricultural products that are exempt from the District permit to operate 

requirements by Rule 11, Section (d). 

(vii) Laboratory operations located at secondary schools, colleges, or 

universities and used exclusively for instruction.

(viii) Touch-up operations.

(ix) Stripping of cured inks, coatings and adhesives. 

(x) Digital printing operations. 

 (xi) Any solvent cleaning, including wipe cleaning, or surface preparation of 

electrical or electronic components, medical devices, laser optics or precision optics 

components. 

(2) Subsection (d)(2) and Section (f) shall not apply to 

(i) Any solvent cleaning, including wipe cleaning, of aerospace components 

not associated with a surface coating operation and provided that the cleaning 

material complies with the requirements of Rule 67.9, Subsection (d)(4). 

(ii) Any solvent cleaning, including wipe cleaning, performed in conjunction 

with welding of 5XXX series aluminum structures for Navy ships and in accordance 

with quality assurance standards for such structures. 

(iii) Any cleaning or surface preparation operation, including wipe cleaning, 

necessary to achieve the required purity of surfaces for precision welding or thermal 

spray operations used in the manufacture of gas turbine engines, provided that the 

combined total amount of such cleaning materials used for these operations at the 

stationary source does not exceed 50 gallons per consecutive 12-months. 

 

Regulation IV -2- Rule 66.1 
(iv) Any cleaning or surface preparation operation, including wipe cleaning, 

where not more than 20 gallons of cleaning materials are used per consecutive 12-

months, provided that the total amount of non-compliant cleaning materials used at 

the stationary source does not exceed 20 gallons per consecutive 12-months; or 

(v) Any cleaning or surface preparation operation, including wipe cleaning, 

where the VOC emissions from cleaning materials do not exceed 150 lbs per 

consecutive 12-months, provided that the total VOC emissions from non-compliant 

cleaning materials used at the stationary source do not exceed 150 lbs per consecutive 

12-months. 

To claim the applicability of the exemptions in Subsection (b)(2), all records of 

monthly purchase or usage of cleaning materials, their VOC content, vapor pressure, or any 

other data necessary to calculate VOC emissions, as applicable, shall be maintained on site 

for three years and made available to the District upon request. 

(c) DEFINITIONS 

For the purpose of this rule the following definitions shall apply: 

(1) "Aerospace Component" means any raw material, partial or completed 

fabricated part, assembly of parts or completed unit of any aircraft, helicopter, missile or 

space vehicle, including mockups, test panels and prototypes. 

(2) "Air-Dried Coating" means any coating that is not heated above 90o

C (194oF) 

for the purpose of curing or drying. 

(3) "Baked Coating" means any coating that is cured or dried in an oven where 

the oven air temperature exceeds 90o

C (194oF). 

 (4) "Coating" means a material which can be applied as a thin layer to a substrate, 

and which either dries or cures to form a continuous solid film or impregnates a substrate 

for protective, decorative, or functional purposes. Such materials include, but are not 

limited to, paints, varnishes, sealers, lacquers, and stains but exclude adhesives. 

(5) “Digital Printing Operation” means an operation that uses a printing device 

guided by a computer-driven machine to transfer an electronic image to a substrate through 

the use of inks, toners, or other graphic materials. Digital printing operations also include 

associated surface preparation, solvent cleaning, and the cleaning of application equipment. 

 

 (6) "Dip Coat" means a coating application method accomplished by dipping an 

object into the coating material. 

 

 (7) "Electrical Components" means internal components such as wires, windings, 

stators, rotors, magnets, contacts, relays, energizers, and connections in an apparatus that 

generate or transmit electrical energy including, but not limited to, generators, 

transformers, and electric motors. 

Regulation IV -3- Rule 66.1 
 (8) "Electronic Components" means components or assemblies of components 

including, but not limited to, circuit card assemblies, printed wire assemblies, printed 

circuit boards, soldered joints, ground wires, bus bars, and other electrical fixtures, except 

for the cabinet in which the components are to be housed. 

(9) "Electrostatic Spray" means a coating application method accomplished by 

charging atomized paint particles for deposition by electrostatic attraction. 

(10) “Exempt Compound” means the same as defined in Rule 2. 

 

 (11) "Existing Operation or Process" means a surface coating operation or other 

process emitting VOCs for which a complete application for an Authority to Construct in 

San Diego County was submitted before February 24, 2010. Wipe cleaning operations that 

are exempt from permit requirements per Rule 11 before February 24, 2010, are considered 

existing operations. 

 (12) "Flow Coat" means a coating application method accomplished by flowing a 

stream of coating over an object. 

(13) "Hand Application Method" means a coating application method accomplished by applying a coating by manually held, non-mechanically operated equipment. 

Such equipment includes, but is not limited to, paintbrushes, hand rollers, rags and sponges. 

 (14) "High-Volume Low-Pressure (HVLP) Spray" means a coating application 

method which uses pressurized air at a permanent pressure between 0.1 and 10.0 psig, not 

to exceed 10.0 psig, measured at the air cap of the coating application system. 

 

 (15) "Low-Solids Coating" means a coating containing one pound of solids or less 

per gallon of material, as supplied. 

 (16) "Medical Device" means an instrument, apparatus, implement, machine, 

contrivance, implant, in vitro reagent or other similar article including any component or 

accessory, that is intended for use in the diagnosis of disease or other conditions or in the 

cure, mitigation, treatment, or prevention of disease, or is intended to affect the structure or 

any function of the body. 

 (17) "New Operation or Process" means a surface coating operation or other 

process emitting VOCs for which a complete application for an Authority to Construct in 

San Diego County was submitted on or after February 24, 2010. 

(18) "Organic Solvent" means any substance containing an organic compound or 

combination of organic compounds which is liquid at atmospheric pressure and ambient 

temperature and which is used as a reactant, diluent, thinner, dissolver, viscosity reducer, or 

cleaning agent, or for other similar purposes. 

 

Regulation IV -4- Rule 66.1 
 (19) "Operation" means any process that includes one or more pieces of equipment 

linked by the process flow and resulting in a product that cannot be made if any piece of 

equipment is removed or not functioning. 

 

 (20) "Precision Optics Components" means the components used to create high 

resolution images in optical devices. 

 

(21) "Research and Development Operation" means a small scale operation for the 

purpose of creating new or improved processes or products, that is conducted by technically 

trained personnel under the supervision of a research director, and is not used in the 

manufacture of products for sale or exchange for commercial profit, other than the firstarticle deliverable product.

 

(22) "Roll Coat" means a coating application method accomplished by rolling a 

coating onto a flat surface using a roll applicator. 

(23) "Solvent" means any organic solvent. 

(24) "Source" means any article, machine, equipment, contrivance, operation or a 

group of such articles, machines, equipment, contrivances or operations that emits or may 

emit volatile organic compounds. 

(25) "Solvent Cleaning" means the removal of uncured adhesives, inks, coatings, 

and other contaminants such as dirt, soil, and grease from parts, products, tools, machinery, 

equipment or general work area. 

(26) "Surface Preparation" means the cleaning of surfaces by utilizing cleaning 

materials containing VOCs prior to coating, further treatment, sale or intended use. 

(27) "Surface Coating" or "Surface Coating Operation" means all steps involved 

in the application, drying and curing of coatings. 

 

(28) "Touch-up Operation" means the portion of a surface coating operation which 

is incidental to the main coating process but necessary to cover minor imperfections or 

minor mechanical damage incurred prior to intended use. 

(29) "Volatile Organic Compound (VOC)" means the same as defined in Rule 2. 

(30) "VOC Content per Volume of Coatings, Less Water and Exempt Compounds"

means the weight of VOC per combined volume of VOC and coating solids and is calculated 

by the equation provided in Rule 2. 

(31) "VOC Content per Volume of Cleaning Material or Low-Solids Coating”

means the weight of VOC per volume of cleaning material or low-solids coating and is 

calculated by the equation provided in Rule 2. 

Regulation IV -5- Rule 66.1 
(32) "Wipe Cleaning" means a method of surface preparation or solvent cleaning 

that is not conducted in a container but performed by physically rubbing the surface with a 

material such as a rag, paper, sponge or cotton swab moistened with a cleaning material. 

(d) STANDARDS 

(1) Surface Coating and Other Operations 

A person shall not conduct any surface coating or other operation, excluding 

surface preparation and solvent cleaning operations, that may result in emissions of 

volatile organic compounds unless one of the following requirements is satisfied: 

(i) VOC emissions from such operation are less than 5 tons per calendar year, 

excluding emissions from cleaning operations; or 

(ii) VOC emissions are reduced by air pollution control equipment in 

compliance with all the applicable requirements of Section (e); or 

(iii) a surface coating operation is conducted by using air-dried coatings with a 

VOC content not higher than 420 grams/liter (3.5 lbs/gal) of coating, less water and 

exempt compounds, as applied, or by using baked coatings with a VOC content not 

higher than 360 grams/liter (3.0 lbs/gal) of coating, less water and exempt 

compounds, as applied. 

(2) Surface Preparation and Solvent Cleaning Operations 

A person shall not conduct a surface preparation or solvent cleaning operation, 

including wipe cleaning but excluding cleaning of coating application equipment, unless 

the VOC content of cleaning material is 50 grams/liter (0.42 lbs/gal), or less as used, or the 

total VOC vapor pressure of cleaning material is 8 mm Hg at 20o

C (68oF) or less. 

(3) Application Equipment for Surface Coating Operations. 

(i) Coating Application Methods. 

No surface coatings shall be applied unless one of the following application 

methods is used: 

(A) Hand application method, or 

(B) Dip coat, or 

(C) Roll coat, or 

(D) Flow coat, or 

(E) Electrostatic spray, or 

Regulation IV -6- Rule 66.1 
(F) High-volume low-pressure (HVLP) spray. Facilities using HVLP 

spray shall have available on site pressure gauges in proper operating conditions 

to measure air pressure at the air cup, or have manufacturer’s information 

regarding the correlation between the air cap pressure and the handle inlet 

pressure, or 

G) Other coating application methods that are demonstrated to have a 

transfer efficiency equal at a minimum to one of the above application methods, 

and which are used in such a manner that the parameters under which they were 

tested are permanent features of the method. Such coating application methods 

shall be approved in writing by the Air Pollution Control Officer prior to use. 

 

(ii) Cleaning of Coating Application Equipment 

A person shall not use VOC containing materials for the cleaning of coating 

application equipment used in operations subject to this rule unless: 

(A) The cleaning material contains 50 grams or less of VOC per liter of 

material; or 

(B) The cleaning material is flushed or rinsed through the application 

equipment in a contained manner that will minimize evaporation into the 

atmosphere; or 

(C) The application equipment or equipment parts are cleaned in a 

container which is open only when being accessed for adding, cleaning, or 

removing application equipment or its parts and provided that the cleaned 

equipment or its parts are drained to the container until dripping ceases; or 

(D) A system is used that totally encloses the component parts being 

cleaned during the washing, rinsing, and draining processes. 

(e) CONTROL EQUIPMENT 

(1) In lieu of complying with the provisions of Section (d) of this rule, an 

owner/operator may use an air pollution control system which: 

(i) Has been installed in accordance with an Authority to Construct; and 

(ii) Has a combined emissions capture and control device efficiency of at least 

85% by weight. 

Regulation IV -7- Rule 66.1 
(2) A person electing to use control equipment pursuant to Subsection (e)(1) shall 

submit to the Air Pollution Control Officer for approval an Operation and Maintenance 

plan for the proposed emission control device and emission collection system and receive 

approval prior to operation of the control equipment. Thereafter, the plan can be modified, 

with Air Pollution Control Officer approval, as necessary to ensure compliance. Such plan 

shall: 

(i) Identify all key system operating parameters. Key system operating 

parameters are those necessary to ensure compliance with Subsection (e)(1)(ii), such 

as temperature, pressure and/or flow rate; and 

(ii) Include proposed inspection schedules, anticipated ongoing maintenance, 

and proposed recordkeeping practices regarding the key system operating parameters. 

(3) Upon approval by the Air Pollution Control Officer, a person subject to the 

requirements of Section (e) shall implement the Operation and Maintenance plan and shall 

comply thereafter with the provisions of the approved plan. 

(f) RECORDKEEPING REQUIREMENTS 

(1) Any person conducting operations subject to this rule shall maintain a current 

list of each coating, solvent, or other VOC containing material in use, which provides the 

VOC content and all other data necessary to evaluate compliance, including but not limited 

to: 

(i) Manufacturer name and identification for each material containing VOCs; 

and 

(ii) For coatings, other than low-solid coatings, the VOC content expressed in 

grams per liter (lbs/gal), less water and exempt compounds, as applied and mix ratio 

of components, if applicable; and 

(iii) Actual oven drying temperature, if applicable; and 

(iv) For surface preparation and cleaning materials or for low-solid coatings, 

the VOC content expressed in grams per liter (lbs/gal) of cleaning material or lowsolids coating as used, and density and mix ratio of components, if applicable; and 

(v) For other materials containing VOCs, other than surface coatings, surface 

preparation or cleaning materials, the VOC concentration per weight or volume of 

material. 

(2) In addition, any person conducting operations subject to this rule shall: 

(i) Maintain monthly records of the amount of each coating used; and 

Regulation IV -8- Rule 66.1 
(ii) Maintain monthly inventory, purchasing or dispensing records for each 

surface preparation and cleaning material or other VOC containing materials used. 

(3) In addition, any person using control equipment pursuant to Section (e) of this 

rule shall maintain daily records of key system operating parameters as approved in the 

Operation and Maintenance plan pursuant to Subsection (e)(2). Such records shall be 

sufficient to document continuous compliance with Subsection (e)(1)(ii) during periods of 

emission producing activities. 

(4) All records shall be retained onsite for at least three years and made available to 

the District upon request. 

(g) MANUFACTURER AND SUPPLIER INFORMATION 

Any person, who manufactures, sells, offers for sale, or supplies to users in San Diego 

County any coating, coating component, solvent cleaning material, or any other VOC containing 

material that is used in an operation that may be subject to this rule shall provide the following 

information to customers: 

(1) The manufacturer’s name and identification of each coating or coating 

component, surface preparation material, equipment cleaning material or any other material 

containing VOCs; and 

(2) The VOC content of coatings, as supplied, expressed in grams per liter or 

pounds per gallon, less water and exempt compounds; and 

(3) The VOC content of low-solid coatings, as supplied, surface preparation or 

solvent cleaning materials or any other materials containing VOCs in grams per liter or 

pounds per gallon; and 

(4) Any other necessary information enabling a user to comply with the 

requirements of Section (d) of this rule. 

(h) TEST METHODS 

When more than one test method or set of test methods are specified in this Section, a 

violation of any requirement of this rule established by any one of the specified test methods or 

set of test methods shall constitute a violation of the rule. 

(1) The VOC content of coatings containing more than 50 grams of VOC per liter 

of material shall be determined by the Environmental Protection Agency (EPA) Reference 

Method 24 (Determination of Volatile Matter Content, Water Content, Density, Volume 

Solids, and Weight Solids of Surface Coatings, 40 CFR Part 60, Appendix A) or by the 

South Coast Air Quality Management District Method 304 (Determination of Volatile 

Organic Compounds in Various Materials) as they exist on February 24, 2010. 

Regulation IV -9- Rule 66.1 
(2) The VOC content of solvents or coatings containing 50 grams of VOC per liter 

of material or less shall be determined by the South Coast Air Quality Management District 

(SCAQMD) Method 313 (Determination of Volatile Organic Compounds by Gas 

Chromatography/Mass Spectrometry), SCAQMD Method 308 (Quantification of 

Compounds by Gas Chromatography) as they exist on February 24, 2010, or any other 

alternative test methods approved by EPA, California Air Resources Board, and the Air 

Pollution Control Officer. 

(3) The content of methyl acetate, acetone and parachlorobenzotrifluoride 

shall be determined in accordance with the ASTM Test Method D6133-02 (2008) 

(Standard Test Method for Acetone, p-Chlorobenzotrifluoride, Methyl Acetate or t-Butyl 

Acetate Content of Solventborne and Waterborne Paints, Coatings, Resins, and Raw 

Materials by Direct Injection Into a Gas Chromatograph), or its most current version. 

 

 (4) Calculation of total VOC vapor pressure for materials subject to Subsection 

(d)(2) of this rule shall be conducted in accordance with the District's "Procedures for 

Estimating the Vapor Pressure of VOC Mixtures." If the vapor pressure of the liquid 

mixture, as calculated by this procedure, exceeds the limits specified in Subsection (d)(2), 

the vapor pressure shall be determined in accordance with ASTM Standard Test Method 

D2879-97(2007) (Standard Test Method for Vapor Pressure-Temperature Relationship and 

Initial Decomposition Temperature of Liquids by Isoteniscope), or its most current version. 

(5) Measurements of transfer efficiency pursuant to Subsection (d)(3)(i)(G) of this 

rule shall be conducted in accordance with the SCAQMD "Spray Equipment Transfer 

Efficiency Test Procedure for Equipment User," as it exists on February 24, 2010. 

The equivalency of coating application equipment pursuant to Subsection (d)(3)(i)(G) shall 

be determined by the SCAQMD “Guidelines for Demonstrating Equivalency with District 

Approved Transfer Efficient Spray Guns” as they exist on February 24, 2010. 

(6) The overall control efficiency of air pollution control equipment operated 

pursuant to Subsection (e)(1)(ii) shall be determined by multiplying the capture efficiency 

of the emission collection system by the control efficiency of the air pollution control 

device. The control efficiency of the air pollution control device shall be determined using 

EPA Test Methods 25A and/or 18 (40 CFR Part 60, Appendix A) and in accordance with a 

protocol approved by the Air Pollution Control Officer. 

(7) Capture efficiency shall be determined according to EPA Test Method 204 and 

technical document, “Guidelines for Determining Capture Efficiency,” dated January 9, 

1995. Subsequent to the initial compliance demonstration period, appropriate key system 

operating parameters as approved by the Air Pollution Control Officer may be used as 

indicators of the performance of the emission control system. 

(i) COMPLIANCE SCHEDULE 

(1) All new operations or processes subject to this rule shall comply with all 

applicable requirements upon initial startup. 

Regulation IV -10- Rule 66.1 
(2) All existing operations or processes subject to this rule shall comply with all 

applicable requirements no later than February 24, 2011. 

(3) The owner or operator of an existing operation that chooses to comply with the 

rule by installing air pollution control equipment pursuant to Section (e) of this rule shall: 

(i) By August 24, 2010, submit to the Air Pollution Control Officer an 

application for an Authority to Construct and a Permit to Operate an air pollution 

control system as specified in Section (e). 

(ii) By August 24, 2011, comply with all applicable rule requirements. 

Regulation IV -11- Rule 66.1