April 10, 2003 

Placer County APCD 243- 1 Rules and Regulations

RULE 243 POLYESTER RESIN OPERATIONS 

Adopted 4-10-03 

CONTENTS 

100 GENERAL

101 PURPOSE 

102 APPLICABILITY 

103 EXEMPTIONS 

200 DEFINITIONS

201 APCO 

202 CAPTURE EFFICIENCY 

203 CATALYST 

204 CLEANING MATERIAL 

205 CLOSED CONTAINER 

206 CLOSED MOLD SYSTEM 

207 CONTROL DEVICE EFFICIENCY 

208 CROSS-LINKING 

209 CURE 

210 ELECTROSTATIC SPRAY 

211 EMISSION CONTROL SYSTEM 

212 ENCLOSED GUN CLEANER 

213 EXEMPT COMPOUND 

214 FIBERGLASS 

215 GEL COAT 

216 GRAMS OF VOC PER LITER OF MATERIAL 

217 HIGH VOLUME-LOW PRESSURE (HVLP) EQUIPMENT 

218 INHIBITOR 

219 LAY-UP 

220 LOW-VOC EMISSIONS RESIN SYSTEMS 

221 LOW VOLUME-LOW PRESSURE (LVLP) EQUIPMENT 

222 MATERIAL 

223 MONOMER 

224 MONOMER CONTENT 

225 NON-ATOMIZING APPLICATOR 

226 PLEASURE CRAFT 

227 PLEASURE CRAFT COATING 

228 POLYESTER RESIN MATERIALS 

229 POLYESTER RESIN OPERATIONS 

230 POLYMER 

231 POLYMERIZATION 

232 REPAIR 

233 RESIN 

234 SPECIALTY RESIN 

235 TOUCH-UP 

236 VAPOR SUPPRESSANT 

237 VOLATILE ORGANIC COMPOUND (VOC) 

238 WASTE MATERIALS 
April 10, 2003 

Rules and Regulations 243- 2 Placer County APCD

300 STANDARDS

301 SPRAY APPLICATION REQUIREMENTS 

302 PROCESS AND CONTROL REQUIREMENTS 

303 EMISSION CONTROL SYSTEM 

304 CLEANING MATERIAL REQUIREMENTS 

305 STORAGE AND DISPOSAL REQUIREMENTS 

306 COMPLIANCE DATES 

400 ADMINISTRATIVE REQUIREMENTS

401 PROHIBITION OF SPECIFICATION 

402 PROHIBITION OF SALE 

403 SALE OF SOLVENTS 

404 OPERATION AND MAINTENANCE PLAN 

500 MONITORING AND RECORDS

501 RECORDKEEPING 

502 RECORD RETENTION 

503 TEST METHODS 
April 10, 2003 

Placer County APCD 243- 3 Rules and Regulations

100 GENERAL 

101 PURPOSE: To reduce the emissions of Volatile Organic Compounds (VOC) from polyester 

resin operations at each stage of the polyester resin process. 

102 APPLICABILITY

102.1 Geographic: The provisions of this rule apply to all commercial and industrial stationary 

facilities performing polyester resin operations, including pleasure craft refinishing, 

anywhere in Placer County. 

102.2 Application: This rule applies to any person who: 

102.2.1 Manufactures, sells, offers for sale or supplies polyester resins for use in the 

District; or 

102.2.2 Uses polyester resins; or 

102.2.3 Uses a surface preparation solvent, a cleanup solvent or a stripper; or 

102.2.4 Solicits, requires the use of, or specifies the application of any polyester 

resins, surface preparation solvent, cleanup solvent, or stripper that does not 

comply with this rule. 

102.3 Severability: If a court of competent jurisdiction issues an order that any provision of 

this rule is invalid, it is the intent of the Board of Directors of the District that the other 

provisions of this rule remain in full force and effect, to the extent allowed by law. 

103 EXEMPTIONS 

103.1 Partial Exemption, Touch-Up and Repair: The provisions of Section 300 of this rule, 

Standards, shall not apply to touch-up and repair operations. 

103.2 Partial Exemption, Low Usage of Resin Materials: The provisions of this rule, except for 

Sections 501 and 502, shall not apply to any person operating a polyester operation 

where the volume of polyester resin materials used in any month is less than 20 gallons. 

103.3 Partial Exemption, Low Usage of Cleaning Materials: The provisions of Section 304 of 

this rule shall not apply to the cleaning of molds, spray equipment or other dispensing 

equipment tools used in gel coat or specialty resin operations that come in direct contact 

with polyester resin products, provided that the total volume of the cleaning materials 

used in any month does not exceed 16 gallons. 

103.4 Pleasure Craft Exemption: The provisions of this rule shall not apply to pleasure craft 

repair and maintenance operations that do not involve polyester resin materials. 

103.5 Exemption From Rule 219: The provisions of Rule 219, Organic Solvents, shall not 

apply to polyester resin operations as defined in Rule 243. 

200 DEFINITIONS 

201 APCO: Air Pollution Control Officer. 

202 CAPTURE EFFICIENCY: Expressed in percent, capture efficiency is the ratio of the weight of 

the VOC in the effluent stream entering a control device to the weight of the VOC emitted from 

polyester resin operations, both measured simultaneously in accordance with Subsection 503.3, 

and calculated by the following equation: 
April 10, 2003 

Rules and Regulations 243- 4 Placer County APCD

 Wc

Capture Efficiency = -------- X 100 

 We

Where: Wc = Weight of VOC entering the control device 

We = Weight of VOC discharged from the coating operations

203 CATALYST: A substance added to resin to initiate or promote polymerization. 

204 CLEANING MATERIAL: Any material containing a volatile organic compound (VOC) and used 

to clean hands, work areas, tools, molds, application equipment, and any other equipment 

related to a polyester resin operation. 

205 CLOSED CONTAINER: A container, which has a cover where the cover meets with the main 

body of the container without any visible gaps between the cover and the main body of the 

container. 

206 CLOSED MOLD SYSTEM: A method of forming objects from polyester resin material by 

placing the polyester resin material in a confining mold cavity and applying pressure and/or heat. 

207 CONTROL DEVICE EFFICIENCY: Expressed in percent, control device efficiency is the ratio of 

the weight of the VOC removed by the control device from the effluent stream entering the 

control device to the weight of VOC in the effluent stream entering the control device, both 

measured simultaneously in accordance with Subsection 503.4, and calculated by the following 

equation: 

(Wc – Wa) 

Control Device Efficiency = -------------- X 100 

 Wc

Where: Wc = Weight of VOC entering the control device 

 Wa = Weight of VOC discharged from the control device 

208 CROSS-LINKING: The process of chemically bonding two or more polymer chains together. 

209 CURE: To polymerize, e.g., to transform from a liquid to a solid or semi-solid state to achieve 

desired product physical characteristics, including hardness.

210 ELECTROSTATIC SPRAY: Equipment used to apply materials by charging atomized particles, 

which are deposited by electrostatic attraction. 

211 EMISSION CONTROL SYSTEM: A system for reducing emissions of VOC from polyester resin 

operations. It consists of (1) equipment, which captures the emissions from the polyester resin 

process and transports them to the control device, and (2) a VOC control device, which destroys 

the VOC or otherwise limits the emission of VOC to the atmosphere. The capture efficiency and 

the control device efficiency are calculated in accordance with Subsections 503.3 and 503.4, 

respectively. 

The Emission Control System Efficiency is calculated by the following equation: 

Capture Efficiency,% X Control Device Efficiency,% 

Efficiency,% = ------------------------------------------------------------------------ 

100 
April 10, 2003 

Placer County APCD 243- 5 Rules and Regulations

212 ENCLOSED GUN CLEANER: 

212.1 A device that is used for the cleaning of spray guns, pots, cups and hoses, that has an 

enclosed solvent container, is not open to the ambient air when in use and has a 

mechanism to force the cleanup material through the gun while the cleaner is in 

operation: 

or 

212.2 A device that is used for the cleaning of spray guns, pots, cups and hoses, that has a 

remote reservoir, uses non-atomized solvent flow to flush the spray equipment and 

collects and returns the discharged solvent to the remote reservoir. 

213 EXEMPT COMPOUND: Any organic compound, which is exempt from the category of Volatile 

Organic Compounds (VOC), and is listed in District Rule 102, Definitions. 

214 FIBERGLASS: A glass fiber, similar in appearance to wool or cotton fiber. 

215 GEL COAT: A polyester resin topcoat that provides a cosmetic enhancement and improves 

resistance to degradation from exposure to the environment. A gel coat may be either 

pigmented or clear. 

216 GRAMS OF VOC PER LITER OF MATERIAL: The weight (in grams) of VOC per liter of 

material shall be calculated using the following: 

 (WV - WW - WEC) 

 Weight of VOC per volume of material = --------------------------- 

WM

 Where: WV = Weight of all volatile compounds, in grams 

WW = Weight of water, in grams 

 WEC = Weight of compounds listed as exempt from the definition of VOC, per 

Section 237, in grams 

 WM = Volume of material, in liters 

217 HIGH VOLUME-LOW PRESSURE (HVLP) EQUIPMENT: Spray equipment used to apply 

coatings by means of a gun which operates between 0.1 and 10.0 psig air pressure, measured 

dynamically at the center of the air cap and at the air horns. 

218 INHIBITOR: A substance used to slow down or prevent a chemical reaction. 

219 LAY-UP: A hand application technique of composite materials using a bucket and a paint 

brush, a paint roller or other hand-held method of application. 

220 LOW VOC EMISSIONS RESIN SYSTEMS: Polyester resin materials, which contain vapor 

suppressants to reduce monomer evaporation loss. 

221 LOW VOLUME-LOW PRESSURE (LVLP) EQUIPMENT: Spray equipment used to apply 

coatings by means of a gun which operates between 0.1 and 10.0 psig air pressure, and air 

volume less than 15.5 cfm per spray gun and which operates at a maximum fluid delivery 

pressure of 50 psig.

222 MATERIAL: Any material containing VOC, including but not limited to, resin, pigmented gel 

coat, catalyst, stripper or cleaning solvent. 

223 MONOMER: A relatively low-molecular-weight organic compound that combines with itself, or 

other similar compounds, to become a cured thermosetting resin. 
April 10, 2003 

Rules and Regulations 243- 6 Placer County APCD

224 MONOMER CONTENT: The amount of monomer in a batch of polyester resin material, 

expressed as a percentage of the total weight of the batch. It shall be calculated by using the 

following three equations: 

224.1 Batch weight WBB = WR + WF + WP + WO

 Where: WR = Resin weight 

 WF = Filler weight 

 WP = Pigment weight 

 WO = Other additives weight 

 WSP

224.2 Monomer weight, WM = WR X----------- 

 100 

 Where: WR = Resin weight in batch 

 WSP = % Monomer in resin, per mfgr’s. specification. 

 WM

224.3 Monomer content, % = -----------X 100 

 WBB

225 NON-ATOMIZING APPLICATOR: Equipment used to apply materials by use of fluid pressure 

without forming an atomized spray. 

226 PLEASURE CRAFT: Boats or other water vessels, which are manufactured or operated 

primarily for recreational purposes, or leased, rented or chartered to a person or business for 

recreational purposes. 

227 PLEASURE CRAFT COATING: Any unsaturated polyester resin material applied by brush, 

spray, roller or other means to a pleasure craft.

228 POLYESTER RESIN MATERIALS: Include but are not limited to, unsaturated polyester resins 

such as isophthalic, orthophthalic, halogenated, bisphenol-A, vinyl ester, or furan resins; crosslinking agents, catalysts, gel coats, inhibitors, accelerators, promoters, and any other VOCcontaining materials in polyester operations.

229 POLYESTER RESIN OPERATIONS: The production or rework of products by mixing, pouring, 

hand lay-up, impregnating, injecting, forming, winding, spraying, and/or curing unsaturated 

polyester resin materials with fiberglass, fillers, or any other reinforcement materials, and 

associated cleanup. 

230 POLYMER: A chemical compound comprised of a large number of chemical units, which is 

formed by the chemical linking of monomers. 

231 POLYMERIZATION: A chemical process where liquid materials are transformed into a solid or 

semi-solid state to achieve desired product physical properties, including hardness. 

232 REPAIR: The part of the fabrication process that requires the addition of polyester resin 

material to one or more portions of a previously fabricated product in order to mend structural 

damage. 

233 RESIN: Any of a class of organic polymers of natural or synthetic origin used in reinforced 

products to surround and hold fibers or filler particles, and is solid or semi-solid in the cured 

state. 
April 10, 2003 

Placer County APCD 243- 7 Rules and Regulations

234 SPECIALTY RESIN: Any halogenated, furan, bisphenol-A, vinyl-ester, or isophthalic resin used 

to make products for exposure to one or more of the following extreme environmental 

conditions: acute or chronic exposure to corrosive agents, caustic agents, acidic agents or 

flame. 

235 TOUCH-UP: The part of the fabrication process that is necessary to cover minor imperfections. 

236 VAPOR SUPPRESSANT: A substance added to resin to minimize the outward diffusion of 

monomer vapor into the atmosphere.

237 VOLATILE ORGANIC COMPOUND (VOC): Any chemical compound, which meets the 

definition of VOC described in District Rule 102, Definitions. 

238 WASTE MATERIAL: Material including, but not limited to, scraps resulting from cutting or 

grinding operations, any paper or cloth used for cleaning operations, waste resins and any other 

spent cleaning materials. 

300 STANDARDS 

301 SPRAY APPLICATION REQUIREMENTS: Spray application of polyester resin materials shall 

be performed using one or more of the following application methods: 

301.1 Non-Atomizing Applicator; 

301.2 High volume-low pressure (HVLP) spray gun; 

301.3 Low volume-low pressure (LVLP) spray gun; 

301.5 Electrostatic spray; 

301.6 Any other equivalent method, which has been approved in writing by the APCO and the 

U. S. Environmental Protection Agency. 

302 PROCESS AND CONTROL REQUIREMENTS: Each polyester resin operation shall comply 

with one of the following process or control requirements: 

302.1 Low VOC Polyester Resin Materials: Use only materials with the following not-toexceed monomer content: (Monomer content is as applied, based upon the 

manufacturer’s specifications and is calculated per Section 224). 

302.1.1 Resins (except for specialty resins and gel coats): Not to exceed monomer 

content of 35% by weight, as applied. 

302.1.2 Pigmented Gel Coats: Not to exceed monomer content of 45% by weight, as 

applied. 

302.1.3 Specialty Resins and Clear Gel Coats: Not to exceed monomer content of 

50% by weight, as applied. 

302.2 Vapor Suppressant: Use polyester resin material containing a vapor suppressant which 

limits weight loss from VOC emissions to no more than 60 grams per square meter. 

302.3 Closed Mold: Use a closed mold system. 

303 EMISSION CONTROL SYSTEM: As an alternative to Section 302, the owner/operator of a 

polyester resin operations facility may install and operate an emission control system. The 

emission control system shall be an acceptable alternative if it meets all of the following 

requirements: 
April 10, 2003 

Rules and Regulations 243- 8 Placer County APCD

303.1 Permit: Owner or Operator shall apply for and receive a Permit-to-Operate from the 

APCO, pursuant to Rule 501, General Permitting Requirements. 

303.2 Efficiency: Owner or operator shall provide an overall system efficiency of not less than 

85% by weight, as determined per Subsections 503.3 and 503.4, and calculated per 

Section 211. 

303.3 Operation and Maintenance Plan: Plan shall comply with the provisions of Section 404. 

304 CLEANING MATERIAL REQUIREMENT: Unless used in an enclosed gun cleaner, the 

maximum allowable usage of cleaning materials that either exceed 1.7 pounds VOC per gallon, 

or have an initial boiling point less than 190°C, is four gallons per day. If the usage of these 

materials exceeds four gallons per day, a cleaning material reclamation system shall be used. 

Such a system shall operate at a minimum of 80% recovery efficiency. Solvent residues from 

on-site reclamation systems shall not contain more than 20 % VOC by weight, as determined 

per Subsection 503.7. 

305 STORAGE AND DISPOSAL REQUIREMENTS

305.1 Closed Containers: Closed containers shall be used for the storage of all polyester 

resin materials, cleaning materials, freshly-cured resin scraps and any other unused 

VOC-containing materials except when being accessed for use. 

305.2 Self-Closing Containers: Self-closing containers shall be used in such a manner to 

effectively control VOC emissions to the atmosphere for the disposal of all polyester 

resin materials, cleaning materials, waste materials and any unused VOC-containing 

materials. 

306 COMPLIANCE DATES

306.1 Any person subject to the requirements of this rule shall be in compliance by October 

13, 2003. 

306.2 Facilities operating prior to the date of adoption of this rule, and electing to install and 

operate an emission control system pursuant to the requirements of Section 303, shall 

have the control system installed and operating by October 13, 2004. 

400 ADMINISTRATIVE REQUIREMENTS 

401 PROHIBITION OF SPECIFICATION: No person shall require for use or specify the application 

of any gel coat or polyester resin subject to the provisions of this rule that does not meet the 

limits and requirements of this rule, where such applications result in a violation of this rule. The 

requirements of this Section shall apply to all written or oral contracts. 

402 PROHIBITION OF SALE: No person shall sell or offer for sale, any gel coat or polyester resin 

material subject to the provisions of this rule, that does not meet the limits and requirements of 

this rule where such applications result in a violation of this rule. 

403 SALE OF SOLVENTS: Any person who sells any solvent subject to this rule shall make 

available to the purchaser at the time of sale, the following information: 

403.1 The solvent type by name, code and manufacturer. 

403.2 The maximum VOC content of the cleanup solvent, as applied, expressed as grams 

VOC per liter of material as determined pursuant to Section 216. 

403.3 Recommendations regarding thinning, reducing or mixing with any solvent, as 

applicable. 
April 10, 2003 

Placer County APCD 243- 9 Rules and Regulations

404 OPERATION AND MAINTENANCE PLAN: A person using an emission control system 

pursuant to Section 303, as a means of alternate compliance with this rule, shall submit an 

Operation and Maintenance Plan for the emission control system to the APCO for approval. A 

person proposing to install a new emission control system as a means of alternate compliance 

with this rule shall submit in addition to an Operation and Maintenance Plan, an application for 

Authority to Construct, pursuant to Rule 501, General Permit Requirements. The Plan shall 

specify operating and maintenance procedures, which will demonstrate continuous operation of 

the emission control system during periods of emission-producing operations. The Plan shall 

also specify which records must be kept to document these operating and maintenance 

procedures. These records shall comply with the requirements of Sections 501 and 502. The 

Plan shall be implemented upon approval of the APCO. Non-approval by the APCO, with the 

deficiency noted, shall be sent to the applicant, in writing within thirty (30) days of receipt of the 

Plan. The applicant shall have thirty (30) additional days to correct and resubmit the Plan. 

500 MONITORING AND RECORDS 

501 RECORDKEEPING: Any person subject to this rule shall comply with the following 

requirements. 

501.1 Maintain current records, which provide all of the data necessary to demonstrate 

compliance with this rule, including the following information: 

501.1.1 List of all polyester resins, catalysts, solvents and cleaning materials in use. 

501.1.2 Daily usage quantities of the above materials. 

501.1.3 Weight percent of monomer (VOC) in each of the polyester resin materials. 

501.1.4 VOC content (grams/liter) for solvents and cleaning materials used. 

501.1.5 For approved vapor-suppressed resins, the weight loss (grams per square 

meter) during resin polymerization, the monomer weight percent and the gel 

time for each resin. 

501.1.6 The amount of each of the polyester resin materials and cleaning materials 

used during each day of operation. 

501.1.7 The volume of polyester resin materials and cleaning materials used for 

touch-up and repair each day of operation. 

501.1.8 Records of hours of operation and key operating parameters as per Section 

404 for any emission control system. 

502 RECORD RETENTION: All records required by this rule shall be retained and made available 

for inspection by the APCO for the previous 24 month period. 

503 TEST METHODS

503.1 VOC Content: Volatile Organic Compound content shall be determined in accordance 

with EPA Method 24 and calculated per Section 216 of this rule, as applicable. 

503.2 Resin VOC (Monomer) Weight Loss: The “Static Method for Determination of Volatile 

Emissions from Polyester and Vinyl Ester Resins” (Air Resources Board RACT/BARCT 

Guidance, 1991, which is based upon South Coast AQMD Rule 1162 as amended and 

published 7/17/90) shall be used for determining VOC emissions for resins as received 

from the manufacturer. Other applicable test methods may be used if they are approved 

by the APCO, California Air Resources Board and the U.S. Environmental Protection 

Agency

503.3 Emission Capture System Efficiency
April 10, 2003 

Rules and Regulations 243- 10 Placer County APCD

503.3.1 EPA Methods 204, 204A, 204B, 204C, 204D, 204E, and/or 204F, as 

appropriate. 

503.3.2 40 CFR 52.741, “VOC Measurement Techniques for Capture Efficiency”. 

503.4 Emission Control System Efficiency

503.4.1 EPA Method 25A, “Determination of Total Gaseous Organic Concentration 

Using a Flame Ionization Analyzer”. 

503.4.2 EPA Method 18, “Measurement of Gaseous Organic Compound Emissions by 

Gas Chromatography”. 

503.4.3 EPA Method 2 or 2C, as appropriate. 

503.5 VOC Content, Other

503.5.1 ASTM D 3960-81 - “VOC in Paints and Coatings”. 

503.5.2 ASTM D 1078-86 - “Liquid VOC Boiling Range”. 

503.6 Exempt Solvents

503.6.1 ASTM D 4457-85 (GC) or ARB 432 

503.7 VOC Content of Waste Materials

503.7.1 EPA Method 8240, “GC/MS Method for Volatile Organics” for liquid wastes. 

503.7.2 Air Resources Board Method 401, “Gravimetric Purge and Trap”