GUIDANCE DOCUMENT FOR CORRECTING 

VOC RULE DEFICIENCIES 

U.S. ENVIRONMENTAL PROTECTION AGENCY 

REGION IX 

CALIFORNIA AIR RESOURCES BOARD 

APRIL 1991 

 Guidance Document for Correcting 

VOC Rule Deficiencies 

Table of Contents 

Introduction................................................ 1 

Alternative Controls and 

Alternative Methods of Compliance...................... 2 

Capture Efficiency ....

..........7 

Capture Efficiency 7 

Compliance Periods / Averaging Times 10 

Compliant Coating and Graphic Arts 

material Emission Limitation Units 13 

Director's Discretion 17 

Recordkeeping Requirements 24 

Source Applicability and Exemptions 27 

Test Methods 30 

Transfer Efficiency ......

VOC Definition. 

................................ 33 

................................... 

Appendix A: List of All CTG Categories 

Appendix B: Capture Efficiency Model Rule 

. 3 6 

 Introduction 

The purpose of this document is to enhance the ability of districts to develop rules that meet State and Federal criteria. This document does not impose any new requirements 

on districts. Rather, it provides examples and additional explanation of policy and enforceability issues highlighted in EPA's guidance document, Issues Relating to VOC 

Regulation Cutpoints, Deficiencies, and Deviations (the Bluebook). Because guidance concerning RACT levels of stringency is available in the Control Techniques Guidelines 
(CTG) and summarized in the Bluebook, we will not provide a detailed discussion of RACT requirements herein. A listing of all CTGs is found in Appendix A. 

This document should be used to review rules that are already adopted as well as consulted during the rule development process. If after reading this document, you need 

additional clarification, please contact: 

The State Implementation Plan Section 

Air and Toxics Division 

U.S. EPA, Region 9 

(415) 744-1185 

1 

Alternative Controls and Alternative Methods of Compliance

The use of alternative controls for meeting emission limits is fairly common in California volatile organic compound regulations. While alternative controls can provide the 

source with different options for meeting regulatory requirements, they can present enforcement problems for the Agencies involved in their oversight. Examples include: 

equivalency provisions, alternative emission control plans (AECPs), cross-line averaging, and any other type of bubble. 

Alternative Controls are generally acceptable to EPA if the rule contains clearly defined enforceable language (e.g., calculations, test methods, etc.) such that an EPA inspector 

can readily determine compliance. However, provisions which allow averaging of emissions from coating lines or other emission sources must also follow the guidance 

provided in EPA's Emission Trading Policy Statement' (ETPS). lations which contain director's discxeti-on--- (DD),-jor the approval and use-.--of--altern@v-eare not 

acceptablq__as State,i@@m'entation Plan (SIP) revisions 

unless the rule -- clarifies tbL&t-such __ap ovals ubmitted 

p@ __Will be s 

to EPA as a sourcp-specific- e-visi-on-or ,_the rule contains 

ion tn h,- @e@ - (i.e., not requiring 

case EPA approval for the alternative means) and meets @h a-l- _prin@ f@plicability and other requ,iremen_,s as 

described--in- P5 (51 ederal 50; December 4, 

1986). For other exemples of director's discretion, please refer 

to the director's discretion discussion. 

Variances are another alternative method of compliance which are distinct from the methods described above. Because variances must meet special administrative 

requirements, they are discussed separately at the end of this section. 

Examples

1. Equivalence or equivalency. Equivalency allows a source to comply by demonstrating an equivalent emission reduction, usually through the use of control 

equipment. However, these provisions can be deficient if the methodology for determining equivalence is not clearly specified, capture efficiency is not considered, and/or 

APCO discretion is included in the determination. 

-------------------- 

1. With regard to bubbles (and other similar emission trades), the final Emissions Trading Policy remains generally in effect. There may, however, be certain 

circumstances where current bubble requirements should be modified or reinterpreted in light of the changed circumstances brought about by the Clean Air Act Amendments of 

1990. We will attempt to keep states/districts appraised of any changes as they arise. 

2 

 Unapprovable provision: 

A person shall not apply any coating with a VOC content in excess of the specified limits, expressed as grams of VOC per liter of coating applied, excluding water and 

exempt solvents, unless emissions to the atmosphere are controlled to an equivalent level by air pollution abatement equipment with an abatement device efficiency of 

at least 85 percent. 

In order for an inspector to determine equivalence, the rule should specify the test methods and calculations used for determining whether actual emissions would be below the 

emissions expected from compliant coatings. [In addition, the-rule must consider capture efficiency (CE) along with the abatement device efficiency. For further discussion of 

CE requirements, please refer to the section on CE.] 

Approvable provision: 

A person shall not apply any coating with a VOC content in excess of the specified limits, expressed as grams VOC per liter (lbs/gal) of coating applied, excluding water 

and exempt solvents, unless emissions to the atmosphere are controlled to an equivalent level by air pollution abatement equipment with a combined capture and 

control efficiency of 80 percent or greater as needed to achieve an equivalent level of control. Calculations and test methods for determining compliance are described 

under Section XXXX. 

This language is approvable because it considers both capture and control efficiency and specifies the calculations and test methods for determining equivalence. 

2. Alternative Emission Control Plans (AECPs). AECPs (aka, Equivalency, Compensating Reduction, or Bubble) are provisions which allow a source to achieve 

equivale - t @mission reductions by using emission reduction credits generated at a source(s) within a facility to offset noncompliant emissions from another operations within 
the facility. These provisions can be deficient if some or all of the following deficiencies are found in he rule: director's discr-etio-n,__emi - ss ion.averaging beyond a-24hour 

peri6d-,-mC6@6-d--olog-y for determining compliance not stated in the ru

,ile_- ET-P-S--.-g-uid ance-- 1 owe ' d ' . For can coating operao@ns, refer to "Compliance With VOC Emission Limitations for Can Coating Operations" (45 Federal 

Register 80824). 

Unapprovable provision: 

The requirements of Section XXXX shall not apply to any coating, cleaning, or stripping line which complies with an alternative emission control plan which has been 

approved by the APCO and which satisfies the following requirements: 

1. Emissions of VOCS, on.a daily weighted average, shall be no greater than that amount which would result if the affected coating line or lines complied with all 

applicable requirements of this rule ... 

(This example contains only a portion of the actual requirements. Additional requirements such as recordkeeping, a complete list of coatings and coating lines, limitations on 

sources of credit, etc., are not included with this example.) 

The previous language is unapprovable because the provision may hinder EPA's ability to determine compliance. The APCO (or director's) discretion gives the APCO the 

authority to approve this provision independent of the SIP process. Please see the director's discretion section of this document for further information. The provision is not 

consistent with the ETPS requirements, and it lacks enforceable criteria and test methods for an inspector to determine compliance. 

Approvable provision: 

The requirements of Section XXXX shall not apply to any coating, cleaning, or stripping line which complies with an alternative emission control plan (AECP) which has 

been approved by the APCO and which satisfies all of the following 

requirements: 

1. AECP approvals shall be submitted to the Environmental Protection Agency as a source-specific State Implementation Plan (SIP) revision. For purposes of 

federal enforceability, an AECP is not effective until it is submitted to and approved by the EPA as a revision of the SIP pursuant to Section 110 of the Clean Air Act, 42 U.S.C. 

7410. 

2. Emissions of VOCs shall be no greater than that amount which would result if the affected coating line or lines complied with all applicable requirements of this 

rule. 

3. In order to calculate emission reductions, each AECP must establish the source's baseline emissions, which are the product of the average Emission Rate, 

Capacity Utilization, and Hours of Operation for the previous two years of operation (unless another period is demonstrated to be more representative). 

4. Emission reductions used as part of the AECP must be 

surplus, enforceable, permanent, and quantifiable. 

5. Calculations and test methods for determining compliance shall be contained in the AECP ... 

 (This example contains only a portion of the actual requirements. Additional requirements such as recordkeeping, a complete list of coatings and coating lines, limitations on 

sources of credit, etc., are not included with this example.) 

3. Cross-line Averaging. Cross-line averaging is a provision which allows a source to achieve equivalent emission reductions by averaging emissions across 

coating lines or averaging emissions from different coating limits (e.g., topcoat and primer) within a coating line. Cross-line averaging provisions may also include the 

deficiencies described above under AECPS, but it is discussed separately in this document because of the allowance for daily weighted averaging. 

Unapprovable provision: 

The requirements of Section XXXX shall not apply to any coating line or lines which use cross-line averag2Lng as a method of compliance. The method must be 

approved by the APCO and satisfy the following requirements: 

1. Emissions of VOCS, on a daily weighted average, shall be no greater than that amount which would result if the affected coating line or lines complied with all 

applicable requirements of this rule ... 

(This example contains only a portion of the actual requirements. Additional requirements such as recordkeeping, a complete list of coatings and coating lines, limitations on 

sources of credit, etc., are not included with this example.) 

This language is unapprovable because the provision might hinder EPA's effort to determine compliance. The APCO (or director's) discretion could be construed to give the 

APCO the sole authority to approve these provisions independent of the SIP process. Please see the director's discretion section of this document for further information. The 

provision is not consistent with the ETPS requirements, and it lacks enforceable criteria and test methods for an inspector to determine compliance. 
Although cross-line averaging is generally unacceptable, it may be approved for sources as described under Example #2. An EPA accepted emissions averaging method 

would be to allow compliance using a daily weighted average, which allows a source to average emissions on a daily basis, if the averaging is accomplished within the same 

coating line and within the same coating category. 

5 

 Approvable provision using a dai.ly weighted average. 

The requirements of Section XXXX shall not apply to any 

coating line which complies with the following requirements: 

1. Emissions of VoCs, determined using a daily weighted average, shall not be greater than that amount which would result if the coating line complied with the 

requirements of 

this rule. 

2. In order for two or more coatings to qualify for inclusion in a daily weighted average calculation, the coatings 

must be used on the same coating line and/or operation, the 

coatings must be regulated under the same emission limit (e.g., both at 3.5 lbs of VOC/gal less water and exempt compounds), and the coatings must be applied on the same 

day. 

3. Calculations and test methods for determining compliance are described under Section XXXX ... 

(This example contains only a portion of the actual requirements. Additional requirements such as recordkeeping, a complete list of coatings and coating lines, limitations on 

sources of credit, etc., are not included with this example.) 

4. Variances. The granting of a variance (aka, variance order, waiver, or conditional permit) by a district or state does not permanently change or amend the 

underlying SIP requirement. The variance have in the past deferred the final compliance date (with respect to state or local rules) for an individual source or temporarily 

changed the regulation as it applies to an individual source. 

To protect a source from a potential federal enforcement action, the variance must be submitted by the state to EPA as a sourcespecific SIP revision and approved by EPA as 

part of the applicable SIP. All SIP submissions seeking approval of a variance(s) must be accompanied by documentation sufficient to clearly show that the operation of the 

source under the terms of the variance will not interfere with attainment and maintenance of the relevant national ambient air quality standard. A variance ailowing an increase 

in emissions of any nonattainment pollutant or precursor is not approvable, unless the variance includes offsetting emission reductions which result in no net increase in 

emissions of the pollutant(s). 

For additional discussion on variances, see the September 14, 1989 letter, "Variances and Other Hearing Board Orders as SIP Revisions or Delayed Compliance Orders Under 

Federal Law," sent by James D. Boyd, Executive Officer of the California Air Resources Boardi to all Air Pollution Control Officers. 

6 

 Capture Efficiency 

Capture efficiency is a measure of the percentage of volatile organic compounds (VOC) delivered to a control device. Rules are often developed which specify the destruction 

efficiency from control devices but do not specify what percentage of the total VOCs involved are actually delivered to the device. For example, if a control device is limited in a 

rule to controlling 90% of the VOC delivered to it, but only 50% of the VoCs are delivered, then the overall capture and destruction efficiency would be only 45% (90% X 50%), 

and 55% of the VOC would be escaping. Thus, the specification of both the capture efficiency and the control device efficiency is critical to the stringency of rules that regulate 

VOCs through the use of add-on control equipment. 

capture efficiency determinations were emphasized by Appendix D of EPA's Post-87 Policy (52 FR 45105-019). On August 1, 1990, EPA provided the states and districts with 

a copy of EPA's capture efficiency measurement protocols (dated April 16, 1990) and on August 28, 1990, EPA transmitted a model capture efficiency rule. A copy of the 

model rule can be found in Appendix B. The protocols have been tested by EPA in coil coating and graphic arts facilities, but are considered to be applicable to most coating 

and degreasing operations. 

There are three options which the district can use to eliminate capture efficiency deficiencies. 1) Adoption of a capture efficiency method using the EPA model method as the 

recommended option. By doing so, all terms are defined, test schedules can be included (such as annually or after a modification), the monitoring parameters are specified, 

EPA test methods are referenced and reporting requirements are defined. The capture efficiency rule can then be referenced in other rules. 2) The rule can reference that the 

EPA capture efficiency method published in 55 FR 26865, June 29, 1990,.(which is the EPA model method) be used. 3) The district also has the option of developing their own 

test method which must then be approved by EPA. 

The following are actual examples of rule language where control equipment is described. Those examples which are unapprovable by the EPA are followed by revisions 

which would be approvable. 
Examples _ 

1. A provision where the capture efficiency is not specified. 

Unapprovable provision: 

"Install and operate an emissions control system which is designed and operated for the maximum collection of fugitive emissions from.... materials and has a control 

device with an efficiency of 90% or more and is approved by the Control Officer." . 

7 

 This provision is not approvable for two reasons: 1) the amount of VOC collection is not specified or quantified and 2), the provision does not specify the capture efficiency test 

method to be used. (Note: a separate section of this rule defines an EPA approved test method for determining the control device efficiency.) 

Approvable.provision: 

"Install and operate an emissions control system which is designed and operated for the collection of 85% or more of all VOC emissions from.... materials and has a 

control device with an efficiency of 90% or more. The control system must be approved by the Control Officer. The method used to determine the capture efficiency 

shall be conducted by the EPA capture efficiency test method (Rule XXX)." 

As an alternative, the test method in 55 FR 26865, 29 June, 1990 

could be referenced as the capture efficiency test method to use. 

2. A provision where the capture efficiency is given, but the 

test method is not. 

unapprovable provision: 

11... by using an emission control system for reducing emissions of VOC, consisting of collection and control devices which are approved by the Executive Officer or 

his designee and which satisfy the following conditions: 

A) The control device shall reduce emissions from an emission collection system by at least 95% by weight, and 

B) the owner/operator shall demonstrate that the emission collection system collects at least 85% by weight of the emissions generated, and 

C) The VOC content.... 11 

In a separate section of this rule relating to test methods, the method for the determination of the VOC reduction by the control device was given but the method for determining 

the amount of VOCs captured was not. Thus, the overall control of VOC emissions cannot be determined and this provision, while an improvement over Example 1, is not 

approvable. 

Approvable provision: 

Include in the testmethods section the following: 

"The method used to demonstrate that the emission collection system achieves the liraits specified in Subsection X shall be the EPA method cited in 55 FR 26865, 

June 29, 1990.11 

8 

 An alternative approvable provision would be to reference an EPA approved district method or rule for measuring capture efficiency. 

3. Example of an approvable provision in which separate or combined capture and control efficiencies are given.

"All open-top vapor degreasers shall be equipped with a freeboard ratio of 0.75 or greater and at least one of the following control devices: 

(i) a freeboard chiller such that the coldest point of the chilled air blanket, measured along the vertical axis at the center above the solvent 

cleaner, is 400 F or less, or; 
(ii) a hood or enclosure to collect emissions, including emissions from lip exhausts, vented to a control device. The hood or enclosure shall 

collect and transfer at least 90% of all emissions from the degreasing 

unit to the control device. The efficiency of the vapor collection system shall be determined by the EPA test method cited in 55 FR 26865, 29 

June 1990. The control device, such as a carbon adsorber or incinerator, shall be at least 95 efficient in reducing emissions vented from the 

collection system. The efficiency of the control device shall be determined using EPA Reference Method 25, or; 

(iii) a capture and control system as described in (ii) above with an overall capture and control efficiency of at least 85%." 

This provision is approvable because it addresses both control and capture efficiency and the methods to determine them. Part iii sets a limit on the combined system and 

allows for some variation in capture and control efficiencies in order to achieve that limit. 

9 

Compliance Periods / Averaging Times

Emission limitations, compliance test methods, and recordkeeping requirements must be based on time periods consistent with the time frame associated with the national 

ambient air quality standard (NAAQS) for the applicable pollutant. For example, exceedence of (or compliance with) the NAAQS for ozone is based on one hour ozone levels 

recorded over a 24 hour period. Therefore, voc emission limitations and records relating to usage of materials containing VOC need to be kept on no greater than a daily basis. 

 Allowing any of the above to exceed the time frameof the shortest applicable NAAQS would hinder efforts to attain 

that NAAQS. 

Compliance test method averaging times may be shorter than the emission limitation or recordkeeping time period because of excessive costs involved with extended testing. 

For similar reason@, test methods at artificially high temperatures (compared to curing and setting temperatures) are prescribed to assure the completeness of the emission 

measurement, ih lieu of cooler but longer test measurements. Usage records for materials containing VOCs must be kept for periods no longer than that of the emission 

limitation. 

When a time period is not specified, either in the limit, in the compliance test, or in the recordkeeping, instantaneous and continuous compliance and recordkeeping will be 

assumed by EPA to be required. As an analogy, the 55 mile per hour speed limit is enforced on an instantaneous or continuous basis and not as an hourly average because 

no compliance period is stated. 

Under very limited situations of uniform application and production over an extended period of time, averaging ti-mes of 24-hours may be recreated after the fact from 

production run data and coating usage data. Production units (and rejects) must be counted on a daily basis and documented, and uniform quantities of VOC must be applied 

to identical production units over the extended period of time. 

Emission limitations with extended averaging over longer than 24-hours are permitted, by EPA, in rules for VOC under very limited conditions, and only only where daily limits 

are infeasible. (See memorandum from John R. O'Connor, Acting Director, Office of Air Quality Planning and Standards, to Air and Waste management and Air management 

Division Directors, Regions I-X, Subject: Averaging Times for Compliance with VOC Emission Limits - SIP Revision Policy, January 20, 1984, and at Appendix D of the EPA 

Emissions Trading Policy Statement.) The following conditions apply: 

10 

 (1) real reductions in actual emissions consistent with RACT control levels, reflecting'typical (rather than potential or allowable) production rates and operating hours, 

supported with historical data; including limited non-production or equipment down-time credit based on historical data; 

(2) averaging over no longer than 30 days; 

(3) demonstration that long term averaging will not jeopardize either ambient standard attainment or reasonable further progress in the area (this must be accompanied by a showing that the maximum daily increase in emissions 

associated with the long term averaging which is consistent with the approved ozone SIP for the area); and 

(4) sources in areas lacking approved SIP's and showing measured violations,,cannot be considered for long term averages until the SIP has been revised 

demonstrating that attainment and maintenance of RFP (reflecting the maximum daily emiss4@ons from the source with long-term averaging). 

Example

1. Extended averaging time 

Unapprovable Provision 

An alternative control method may be utilized for can end sealing compounds used on cans for fatty foods, in lieu of the limits specified in Section (c). 

The utilization of any combination of emission control device, process and can coatings is allowed, provided the total emissions of VOCs over any one operating day do not 

exceed the average emissions per operating day (over a specified historical period), that would have occurred if can coatings with VOC content equal to the limits specified in 

Section (c) had been used over the historical period, assuming the use of EPA accepted methods. 
In utilizing this interim alternative, emissions may increase up to 110% of the above limit for any particular operating day, provided that average emissions over operating d-ays 

in any calendar week do not exceed the specified daily limits. 

This example uses a daily emission limit based on a historical daily average, which is acceptable. However, the last paragraph renders this provision unapprovable 

because it allows sources to exceed the daily limit by averaging emissions over a period of a week. 

11 

 Approvable Provision 

An alternative control method may be utilized for can end sealing compounds used on cans for fatty foods from January 1, 1986 through July 1, 1987, in lieu of the 

limits specified in Section (c). 

The utilization of any combination of emission control device, process and can coatings is allowed, provided the total emissions of VoCs over any one operating day do not 

exceed the average emissions per operating day over the five year period prior to January 1, 1985, that would have occurred if can coatings with VOC content equal to the 

limits specified in section (c) had been used over the five year 'period, assuming the use of EPA accepted methods 

This determination must be made over a 24 hour period based 

on actual hours of operation. 

12 

 compliant Coating and Graphic Atts Material Emission Limitation 

Units 

Compliant coating and ink limitations must be at least as stringent as the VOC RACT emission rate limits contained in the EPA Control Techniques Guideline (CTG) 

documents, after any/all thinning or dilution with VOC, water, or exempt compounds. To effect this end, the emission rate limitations generally must be expressed in units of 

weight of volatile compounds, less water and exempt compounds (i.e., VOC) per unit volume of VOC and solids, (e.g., grams of VOC/liter of coating) as applied. Exceptions, 

additions and alternatives to the general form of the emission limitation are discussed below. 

If the rule allows compliance to be demonstrated through emission trades between lines or between coatings with different rule limitations, or through the use of add-on 

controls, then the rule must also limit the weight of VOC per unit volume of solids (or weight of VOC per weight of solids for graphic arts). Another acceptable alternative would 

be for the rule to provide for a conversion to a solids basis. The EPA's guidance document, Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations 

(Bluebook) provides an example at its Attachment 3. 

An alternative limitation on the VOC content of graphic arts materials, comparable to carbon adsorption or incineration, is provided in the CTG as, the solvent portion of the ink 

may consist of no-more than 25 volume percent VOC and no less than 75 percent by volume exempt compounds and water. EPA has also approved a generic alternative 

RACT definition for graphic arts, 0.5 pounds of VOC per pound of solids. (See memorandum from Daryl Tyler, EPA/OAQPS, to Director, Air Division, Regions I-X, Subject: 

Alternative Compliance for Graphic Arts RACT, September 9, 

1987.) 

EPA cannot approve limitations which do not exclude water and exempt compounds, which are on other than an "as applied" basis, or which allow averaging across coating 

lines, across coatings with different limitations, or across add-on control devices, without the inclusion other provisions to prevent circumvention or differences due to the 

averaging of different density materials. 

A different equation is sometimes used for coatings which contain zero or sicall amounts of solids (clean-up solvents, wash primers, stains, oils, graphic arts fountain solutions, 

and certain adhesives and adhesive primers). In such products, the amount of coating needed to cover a unit of surface area does not depend on the solids content, as in 

other coatings. However, this form of limitation is not approvable under EPA policy for low solids coatings. 

13 

 certain multicomponent coatings and nonheatset inks polymerize (form solid materials through the crosslinking of molecules) during the curing process. Some of the VOC is 

retained as solids in porous substrates or in the coating. The current Reference Method 24 (RM-24) drives off (captures and measures) these VOC's 

prior to the polymerization. 

Currently EPA recommends that RM-24 with minor modifications be used for multi-component coatings. (See memorandum from John Seitz, Director, Stationary Source 

compliance Division, to Air Compliance Branch Chief, Regions I-X, Subject: Applicability of Environmental Protection Agency (EPA) Method 24 to Multicomponent Coatings, 

June 11, 1990.) These modifications are that (1) all components of the coating are weighed in the proper proportion into the analysis container and mixed together just prior to 

analysis and (2) the mixture is allowed to stand for at least 1 hour, but no more than 24 hours, prior to being oven dried at 110 

degrees C for 1 hour. 
EPA recommends that districts add the above language tc adequately measure the VOC in multicomponent and any other polymerization reaction coatings and inks. The 

second step merely ensures that the catalytic reaction which must occur between the components of the coating has begun or, in some cases, is completed before the coating 

is heated. 

One District has taken this recommendation one step further and applied it to the form of the emission limitation for all coatings and inks which may have components which 

need to become solidified during the curing process. Such general application of the two-step measurement process through reference to separate curing and analysis 

emissions is consistent with EPA policy. 

EPA is investigating potential policy changes relating to low solids coatings and reactive diluents. However, it would be premature to recommend changes based on some 

Districts' perceived resolution of these issues. 

Examples

1. Calculation of compliant coating emission limits Approvable Provision: 

Compliant coating emission limits shall be expressed in units of grams of VOC per liter of coating or ink, less water and exempt compounds, as applied, and shall be 

calculated by the following equation: 

(Ws - Ww - Wec)/(Vm - Vw - Vec) 

14 

 where: 

Ws = weight of volatile compounds evolved analysis, 

in grams 

Ww = weight of water evolved during analysis, in grams 

Wec = weight of exempt compounds evolved during analysis, 

in grams 

weight of volatile compounds evolved analysis, 

in grams 

volume of coating and/or ink, including any thinners 

and diluents applied, in liters 

Vw = volume of water evolved during analysis, in liters 

Vec = volume of exempt compounds evolved during analysis, 

in liters 

2. Calculations for low and zero solids coatings and graphic arts 

materials. 

Unapprovable Provision: 

Calculations for low solids coatings shall be made according 

to the following fomula: 

(Ws - Ww - Wec)/(Vm) 

where: 

Ws = weight of volatile compounds in grams 

Ww = weight of water in grams 

We, = weight of exempt compounds in grams Vm = volume of material in liters. 

Compliant coating emission limits must be expressed in units of grams of VOC per liter of coating or ink, less water and exempt compounds, as applied, and may not be 

calculated by the equation above. 
Approvable Provision: 

The equation listed at 1, above is approvable for low solids

coatings. EPA policy does not address zero solids coatings.

15 

 3. Calculation for Reactive Diluent 

Unapprovable Provision 

The amount of reactive diluent (defined such that VOC remaining in the substrate is excluded) shall be determined by a test method yet to be developed. 

EPA does not recognize a VOC test method that requires testing of 

coatings, inks, etc. on different substrates. 

Approvable Provision: 

Calculations for reactive diluents shall be made according 

to the following fomula: 

(Ws - ww - w ec)/(Vm - Vw - Vec) 

where: 

W, = weight of volatile comp 

w 

w 

v 

ec 

ec 

weight of volatile compounds evolved during 

curing and analysis, in grams 

weight of water evolved during curing and 

analysis, in grams 

weight of exempt compounds evolved during 

curing and analysis, in grams 

volume of material prior to reaction, in liters 

volume of water evolved during curing and 

analysis, in liters 

volume of exempt compounds evolved during 

curing and analysis, in liters 
Compliant coating emission limits must be expressed in units of grams of VOC per liter of coating or ink, less water and exempt compounds, as applied. The Reference Method 

should describe in detail the procedure to be followed. 

16 

Director's Discretion

"Director's Discretion" refers to provisions in rules or regulations which allow a representative of a State or local agency to approve alternatives to the basic provisions of-the 

State or district regulation without further regulatory process. When the director exercises his judgement, the rule is altered from its adopted, approved form without notification, 

evaluation, or approval from the next levels of government (e.g. when done on a local level, the state and EPA have no voice in the approval of 

the alternative). 

EPA cannot approve certain types of director's discretion provisions because, in some cases, judgements made under such provisions may alter the stringency of the federallyapproved SIP. Excess emissions from sources can occur with certain types of director's discretion provisions related to test methods, control requirements, exemptions, etc. 

EPA can approve certain types of director's discretion provisions that only involve minor changes or adaptations to the basic regulation that do not have the potential to change 

the stringency of the federally-approved SIP. 

Please refer to other sections in this guidance document regarding specific requirements for test methods, alternative controls, recordkeeping, etc. 

Examples

The following are examples of approvable director's discretion 

provisions: - 

1. Inclusion of replicable procedures to determine equivalency of 

alternative controls. 

A person shall not refinish Group I vehicles, their parts and components, or Group II vehicles and mobile equipment where color match is required, using any coating with a 

VOC content in excess of the following limits, expressed as grams of VOC per liter (or pounds per gallon) of coating applied, excluding water and exempt solvents, unless 

emissions to the atmosphere are controlled to an equivalent level by air pollution abatement equipment with an overall control efficiency (capture and control) of at least 85% 

and which has been approved in writing by the APCO: (This assumes that a test method is specified in the rule to calculate the 85% and equivalency) . 

17 

 In this example, test methods provide the replicable procedure to calculate the 85% efficiency. The rule must also specify the method used to determine equivalency. Any 

inspector visiting the facility should be able to use the test methods specified in the rule to determine compliance. 

2. Inclusion of replicable procedures by which monitoring requirements may be changed.

The monitoring schedule of paragraphs 1 to 3 of this section 

may be modified as follows: 

(a) After completion of the required annual and quarterly inspections for a period of at least two years, the operator of a refinery may request in writing to the Air 

Pollution Control Board that the monitoring schedule be revised based on the percent of valves leaking. The percent of valves leaking shall be determined by div@Lding the 

sum of valves leaking during current monitoring and valves for which repair has been delayed, by the total number of valves subject to the requirements. This request shall 

include all data that have been developed to justify the following modifications in the monitoring schedule: 

(i) after two consecutive quarterly leak detection periods with the percent of valves leaking equal to or less than 2.0%, an owner or operator may begin to skip one of 

the quarterly leak detection periods for the valves in gas/vapor 

and light liquid service; 

(ii) after five consecutive quarterly leak detection periods with the percent of valves leaking equal to or less than 2.0%, an owner or operator may begin to skip three 

of the quarterly leak detection periods for the valves in gas/vapor and light liquid service. 

(b) If the Executive Officer determines that there is an excessive number of leaks in any given process area, he may require an increase in the frequency of 

monitoring for that process area of the refinery. 

(Test methods are specified in a separate paragraph of this rule.) 

The above example provides replicable procedures to be used by the Air Pollution Control Board to make the determination that the monitoring schedule be revised. It also 

provides replicable procedures for the Executive Officer to make the determination that an increase in the frequency of monitoring is needed. 

3. Inclusion of language to preserve enforceability of federally 

approved limits. 

For purposes of federal enforceability of this article, the EPA is not subject to approval determinations made by the Executive Officer under Sections XX 

and XX. Upon the request of a person who has been granted an exemption under Section XX or XX, an exemption meeting the requirements of the 
Clean Air Act shall be submitted by the Executive Of18 

 ficer to the Envirormental Protection Agency for inclusion in the applicable implementation plan approved or promulgated by the EPA pursuant to Section 110 of the Clean Air 

Act, 42 U.S.C. Section 7410. 

In this example, found in the California State Consumer Products rule, EPA is not bound by any approval determinations made by the Executive Officer, unless and until EPA 

approves the determination as part of the SIP. 

The following are examples of unapprovable director's discretion 

provisions along with their corrections:

1. Discretion in exemptions and recordkeeping requirements: 

Unapprovable provision: 

The requirements of this Section shall not apply to any person who complies with an alternate recordkeeping plan that provides for an enforceable daily record which 

has been approved by the APCO in writing. 

This example has the potential to allow an APCO to exempt a source on the basis of an alternate recordkeeping plan. The APCO has the ability to approve any type of daily 

recordkeeping in order to exempt the source from the requirements of the rule. 

Approvable provision: 

The requirements of this Section shall not apply to any person who complies with an alternative recordkeeping plan, provided that the plan has been submitted to and 

approved by . ARB and EPA. 

In order to be approvable, without the submission of a source specific SIP revision, the rule must state specifically what type of alternative recordkeeping will be allowed. If the 

type of recordkeeping is not stated in the rule, EPA would require a source specific SIP revision to be submitted. The rule also must specify that the application of director's 

discretion would have no impact on the federally-approved SIP. 

2. Discretion in methods of compliance: 

Unapprovable provision: 

For cold solvent cleaning, one of the following control devices (must be used): 

(a) a freeboard such that the freeboard ratio is equal to or greater than 0.75, 

(b) a water cover if the solvent is insoluble in heavier than water, or 

19 

 (c) any other system of equivalent control approved by the 

Executive Officer. 

The above example allows a cold solvent cleaning device to be in compliance if it has one of the control systems described in (a) or (b), or has a system considered equivalent 

by the EO. The rule does not state what types of other equivalent control devices could be used or provide replicable criteria for choosing 

an equivalent control device. 

Approvabl,e provision: 

For cold solvent cleaning, one of the following control 

devices (must be used): 

(a) a freeboard such that the freeboard ratio is equal to or 

greater than 0.75, or 

(b) a water cover if the solvent is insoluble in heavier 

than water, or 

(c) a hood or enclosure to collect all emissions, including 

emissions from lip exhausts, vented to a control device. 

In order to be approvable, the rule should specify all the control systems, as shown above, and include applicable test methods and capture/control efficiencies. If the 

State/District wishes to provide for equivalent means of control, then a description of the equivalent control system being proposed must be submitted to ARB and EPA for 

approval as part of the SIP. An example of that type of language is as follows: 
(d) any other system of equivalent control approved by the Executive Officer and submitted to and approved by ARB and EPA. 

3. Discretion in emission limits: 

Unapprovable provision: 

Within seven months of each compliance date specified by Subsection (d)(5)(ii), the Air Pollution Control Officer (APCO) shall evaluate the VOC reduction efficiency 

actually achieved in practice by equipment used to meet the requirements of Subsection (d)(5)(ii). If the required VOC reduction efficiency cannot be met on an 

ongoing basis, after all reasonable efforts to achieve compliance have been made, the APCO s-hall advise the Air Pollution Control Board and make a recommendation 

to revise this rule to reflect the maximum VOC reduction efficiency that can reasonably be met on an ongoing basis. In the case of such inability to meet the required 

VOC reduction efficiency, the requirements of Subsection (d)(5)(ii) shall be deemed to have been met for the period from the date of final compliance specified in Subsection (d)(5)(ii) until such time as the Air Pollution Control Board acts on the recommendation of the APCO.

20 

 The above example allows the Air Pollution Control Officer the flexibility to alter an emission limit for a particular source and find that source in compliance because it cannot 

meet the requirements of Subsection (d)(5)(ii). This example also provides for the wholesale relaxation of the rule if a source cannot comply with it. The term "reasonable 

efforts" must also be defined in the rule. 

Approvable Provision: 

Within seven months of each compliance date specified by Subsection (d)(5)(ii), the Air Pollution Control Officer shall evaluate the VOC reduction efficiency actually 

achieved in practice by equipment used to meet the requirements of Subsection (d)(5)(ii). If the required VOC reduction efficiency cannot be met on an ongoing basis, 

after all reasonable efforts to achieve compliance have beefi made, the so@rce shall apply to the local District for an alternate emission control plan (AECP). Upon 

approval of the AECP by the APCO, the AECP shall be submitted to and approved by ARB and EPA. 

If the source is unable to continually meet the required VOC reduction efficiency stated in the rule, then an official change, in the form of a source specific SIP revision, is 

required. If a source specific SIP revision were not submitted, the APCO would have the authority to relax the requirements of an officially adopted and approved rule. For 

additional information, see the Section on Alternate Controls. 

4. Discretion in test methods: 

Unapprovable provision: 

The purpose of this rule is to determine essentially all the volatile organic compounds present in the coating as used. The volatile organic content of the coating 

material per volume of coating material, less water, shall be determined by using EPA Reference Method 24 or by any other method approved by the Executive Officer. 

The above example allows an unspecified test method to be used to determine compliance. This provision could allow a district to use a test method which has not yet 

undergone EPA review. If the Executive Officer approved another test method, EPA could be bound by the Executive officer's approval even if EPA disagreed with the 

Exequtive Officer's approval. Since approval of other test methods constitute a modification of the SIP, EPA must be kept in the approval process. (A discussion of other test 

method requirements can be found in the Test Methods section of this document.) 

21 

 A test method not stated in the rule, but selected by the Executive officer, could potentially allow a test method considered to be inappropriate by EPA to be used for 

compliance determinations. 

Approvable provision: 

The purpose of this rule is to determine essentially all the volatile organic compounds present in the coating as used. The volatile organic content of the coating 

material per volume of coating material, less water and exempt compounds, shall be determined by using EPA Reference Method 24. The use of an alternative test 

method may be approved by the APCO, provided the alternative is submitted to EPA as a source specific SIP revision. 

The above example states specifically which test method will be used to determine the amount of volatile organic compounds present in the coating as used. Since the method 

is listed, there is no question as to which method can be used to determine compliance. (This example is also discussed in the Section on Test Methods.) 

5. specification of application methods with director's discretion. 

Unapprovable provision: 

"Application Methods. Effective twelve months from the date of adoption for all coatings, a person shall not apply any coating to any Group I or II vehicles or mobile 

equipment or their parts and components unless one of the following methods is used: 

(1) Electrostatic application equipment, operated in accordance with the manufacturer's recommendations; 
(2) High Volume Low Pressure (HVLP) spray equipment, operated in accordance with the manufacturer's recommendations; 

(3) Any other coating application method which has been demonstrated to the satisfaction of the Executive Officer and for which written approval of the Executive 

Officer has been obtained.-' 

The problem with this provision is in section (3). If this provision were approved by EPA, EPA might be subject to an equipment approval decision made by the Executive 

Officer even if EPA did not agree with the Executive Officer's decision. Thus, the provision is unapprovable because of its potential to modify the SIP without prior EPA 

approval. 

Approvable provisions: 

There are two possible fixes for this unapprovable provision: 

22 

 1. Remove section (3) and amend the rule as new high transfer efficiency processes are presented and verified to the district.

2. Require the source to get ARB and EPA approval as well as the Executive officer approval in section (3). Thus, section (3) might be written as follows: 

(3) Any other coating application equipment which has been demonstrated to the satisfaction of the Executive Officer and the Administrator of EPA, and approved by 

the Executive Officer, the ARB, and the EPA as a SIP revision. 

23 

UnanDrovable provision: 

Effective 60 days after adoption, a person shall not operate any perchloroethylene dry cleaning facility unless any solvent liquid or solvent vapor leaks are repaired immediately. 

The above provision is unapprovable because it does not require the source to maintain records regarding leaking components and repair and maintenance of leaks. 

Approvable provision: 

Effective 60 days after adoption, a person shall not operate any perchloroethylene dry cleaning facility unless any solvent liquid or solvent vapor leaks are repaired 

immediately. 

A daily inspection log shall be maintained. This log shall 

include the following: 

a. Leak(s) found - liquid or vapor - date and time; 

b. Identification of leaking component; and 

C. Leak(s) repaired - date and time. 

The above provision is approvable because it requires the source to maintain specific records so that identification and the repair of leaks can be verified by the daily 

maintenance records. 

2. Exemptions. 

Unapprovable provision: 

The Control Officer shall exempt the following facilities from the provisions of Section X, upon receipt of a petition and verification of qualification. The owner or 

operator of an exempt facility shall petition annually for renewal of the exemption. 

a. Facilities using less than 1200 liters (320 gallons) per year of perchloroethylene. 

In the above section recordkeeping requirements are needed to record the usage of perchloroethylene in order for the source to prove eligibility for the exemption specified 

above. 

Approvable provision: 

XX. Recordkeeping 
1. Any person subject to this Rule shall maintain records on a daily basis showing the amount of perchloroethylene consumed in the dry cleaning process. 

25 

 2. Such records shall be retained and available for inspection for the previous 24 month period. 

3. A daily inspection log shall be maintained. 

In the above section daily recordkeeping might be needed for 

other purposes besides proving the exemption. 

For further guidance, districts can refer to EPA's guidance document entitled "Recordkeeping Guidance Document for Surface Coating operations and the Graphic Arts 

Industry." 

2 6 

 Una-nrovable provision: 

Effective 60 days after adoption, a person shall not operate any perchloroethylene dry cleaning facility unless any solvent liquid or solvent vapor leaks are repaired 

immediately. 

The above provision is unapprovable because it does not require the source to maintain records regarding leaking components and repair and maintenance of leaks. 

Approvable provision: 

Effective 60 days after adoption, a person shall not operate any perchloroethylene dry cleaning facility unless any solvent liquid or solvent vapor leaks are repaired 

immediately. 

A daily inspection log shall be maintained. This log shall 

include the following: 

a. Leak(s) found - liquid or vapor - date and time; 

b. Identification of leaking component; and 

C. Leak(s) repaired - date and time. 

The above provision is approvable because it requires the source to maintain specific records so that identification and the repair of leaks can be verified by the daily 

maintenance records. 

2. Exemptions. 

Unapprovable provision: 

The Control officer shall exempt the following facilities from the provisions of Section X, upon receipt of a petition and verification of qualification. The owner or 

operator of an exempt facility shall petition annually for renewal of the exemption. 

a. Facilities using less than 1200 liters (320 gallons) per year of perchloroethylene. 

In the above section recordkeeping requirements are needed to record the usage of perchloroethylene in order for the source to prove eligibility for the exemption specified 

above. 

Approvable provision: 

XX. Recordkeeping 

1. Any person subject to this Rule shall maintain records on a daily basis showing the amount of perchloroethylene consumed in the dry cleaning process. 

25 

 source Applicability and Exemptions

Rules often contain provisions which only apply to larger sources or which exempt smaller sources. Such provisions must be consistent with Control Techniques Guideline 
(CTG) requirements and any EPA policy requirements. Appendix A lists the CTGs issued by EPA and a more detailed summary of each CTG's requirements can be found in 

Attachment 1 of EPA's guidance document, Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations (Bluebook). Applicability requirements or exemptions 

in district rules must be consistent with-CTG requirements and EPA policy requirements. 

Applicability requirements and exemption allowances depend upon the source category. This section is not meant to provide a complete description of what must be covered 

by each sour6e category. Instead, it will present examples of both unapprovable and approvable provisions and a discussion of the issues surrounding the examples. 

Examples

1. CTG sources exempted from RACT requirements. 

Unapprovable provision: 

The objective of this rule is to limit emissions'of vocs from organic liquid loading facilities. For the purposes of this rule, organic liquid loading facilities are those 

facilities which load more than 20,000 gallons of organic liquids with a true vapor pressure of at least 1.5 psia at loading conditions in any one day. 

The above provision indicates that the rule applies only to organic liquid loading facilities that load more than 20,000 gallons of organic liquids per day, defined as bulk terminals 

per EPA's definition of such facilities. However, EPA also requires control of emissions at bulk plants, defined as those facilities which load less than or equal to 20,000 gallons 

of organic liquids per day. As specified in EPA's CTG for Bulk Gasoline Plants, EPA-450/2-77-035, EPA will allow an exemption for facilities which load less than 4,000 gallons 

of organic liquids per day from emission control requirements. Except for this throughput exemption, however, all other existing bulk plant facilities must employ emission 

controls per EPA's bulk plant CTG. The above provision can be made approvable by additionally requiring that facilities which load between 4,000 and 20,000 gallons per day 

of organic liquids be subject to the requirements as listed in the Bulk Plant CTG. 

27 

 3. Exemption not consistent with EPA policy. 

Unapprovable provision: 

(j) Exemptions 

(1) The provisions of subparagraph (b)(1) of this rule 

shall not apply to coatings with separate formulations that are used in volumes of less than 20 gallons per year provided that the total usage by a facility is less than 

200 gallons of such formulations applied annually. 

EPA policy (G.T. Helms memo titled "Exemption for Low-Use Coatings, 10 August 1990) allows an exemption of up to 55'gallons of such formulations per year per facility, 

irrespective of the amount allowed for each separate formulation. The above provision effectively exempts up to 145 gallons more of separate coating formulations per facility 

per year than the requirements of EPA's policy. The provision would be approvable if the 200 gallons total annual limit per facility were changed to 55 gallons. 

Approvable provison: 

(j) Exemptions 

(1) The provisions of subparagraph (b)(1) of this rule 

shall not apply to coatings with separate formulations that are used in volumes of less than 20 gallons per year provided that the total by a facility is less than 55 gallons 

of such formulations applied annually; or 

(1) The provisions of subparagraph (b)(1) of this rule shall not apply to coatings with separate formulations provided that the total by a facility is less than 55 gallons 

of such formulations applied annually. 

29 

Test Methods

EPA's guidance document, ISSUES RELATING TO VOC REGULATION CUT . POINTS, DEFICIENCIES, AND DEVIATIONS, Clarification to Appendix D of November 24, 

1987 Federal Register (Bluebook) states that the most current VOC EPA test methods should be used and that all test methods must be specified in the SIP. The Bluebook 

contains a list of recommended test methods and procedures that can be used for Group I, II and III CTG categories. 

In general, district rules should specify EPA Reference Methods for determining compliance wherever a test method is required. 

These methods are listed in 

Reference ethods.' In some Method 

exists, other EPA-approved test methods nay be used. EPA approval of test methods is critical to ensure consistency and accuracy in compliance determinations. In no 

instance will a test method be approved for use in a SIP unless it has been reviewed and approved by EPA. A list of EPA-approved test methods developed by the American 

Society for Testing and Materials (ASTM) is given at the end of 40 CFR Part 60 under the heading, Material Approved for Incorporation by Reference. Some test methods 

developed by the California Air Resources Board (CARB) have also been approved by EPA. 

Several districts within California have chosen to develop and use their own test methods for determining compliance, claiming that their methods are either cheaper, more 

efficient or more stringent than comparable EPA Reference Methods. EPA recognizes that some district test methods may, in fact, be an improvement over EPA methods. 

However, all test methods must still be evaluated and approved by EPA before the rule containing the test method can be approved into the SIP. 
Several examples are given below of provisions taken from actual district rules which are not approvable by EPA because they fail to meet EPA requirements regarding test 

methods. Following each example is a discussion of the problem and suggested a approvable provision. 

Examples

1. No test-method given. 

Unapprovable provision: 

Gas Ti @t - is defined as a concentration of VOC, measured 1 cm from any source and expressed as methane, less than or equal to 10,000 ppm above background. 

3 0 

 While defined correctly, this provision is unapprovable because it does not specify a test method with which to measure the VOC concentration above background. This 

provision can be made approvable by including an EPA approved test method for making the 

compliance determination. 

Approvable provision: 

Gas Tiqht - is defined as a concentration of VOC, measured 1 cm from any source and expressed as methane, less than or equal to 10,000 ppm above background, as 

determined by EPA Reference Method 21. 

2. Use of a non EPA-approved test method. 

Unapprovable provision: 

For purposes of applicability, the true vapor pressure shall be determined by ASTM Method D323-89 - Vapor Pressure of Petroleum Products (Reid Method). 

ASTM test methods are identified by a method number preceded by a letter of the alphabet (in this case D323) followed by a two digit number indicating the date the test 

method was developed or last reviewed". The test method referenced in the above provision was last reviewed in 1989. A check of the list of EPA approved ASTM methods at 

the end of 40 CFR Part 60, however, indicates that only an earlier version of ASTM method D323 has been approved by EPA: D323-82. Without review and approval by EPA 

of the 1989 version of ASTM D323, the above provision is unapprovable. This provision can be made approvable by referencing the EPA approved version of the ASTM 

method instead of the unapproved revised version of the method, or by submitting the 1989 version of the ASTM method with the revised rule for EPA review and approval into the SIP. 

Approvable provision: 

For purposes of applicability, the true vapor pressure shall be deteridined by ASTM Method D323-82 - Vapor Pressure of Petroleum Products (Reid Method). 

If a district chooses to use a non EPA-approved test method, a copy of the method should be sent to EPA for review along with a copy of the rule to which it applies. Since the 

review process for a test method will likely take longer than that for a rule, the method and corresponding rule should be sent to EPA at the earliest possible date. The district 

should include documenta-------------------- 

2. ASTM reviews all methods periodically and will change the date of the method to reflect the latest review, whether or not the method has been-altered. 

3 1 

 tion demonstrating that the method is accurate, provides repeatable results, is appropriate for the rule provision in question, and, if applicable, produces results consistent and 

equivalent to those obtained with any existing EPA Reference Method that it is replacing. Copies of test methods and documentation should be sent to: 

Chief, State Implementation Plans Section 

U.S. EPA, Region 9 

75 Hawthorne Street (A-2-3) 

San Francisco, CA 94105 

3. More than one test method listed. 

Unapprovable provision: 

All gasoline delivery vehicle tanks shall be maintained in a gas-tight condition. The gas-tight condition of the tanks shall be determined by either EPA Reference 

Method 27 or ARB 

Method 2-5. 

In some cases a District may choose to list more than one EPAapproved test method for determining compliance. Even though both test methods listed above are EPAapproved, they may not produce the same results. Thus, it is possible that one method may indicate a violation while the other indicates compliance with the rule provisions. 

To avoid such discrepancies, the district should only reference one of the two methods in the rule. Since both methods have been approved, either would be acceptable for 

determining compliance. In the event that a District insists on listing both methods, the rule must also state that a violation determined by either test method shall constitute a 

violation of the rule. . 
Approvable provision: 

All gasoline delivery vehicle tanks shall be maintained in a vapor-tight condition. The gas-tight condition of the tanks shall be determined by either EPA Reference 

Method 27 or ARB Method 2-5. A violation determined by either tes . t method shall constitute a violation of the rule. 

32 

Transfer Efficiency (TE)

Transfer efficiency requirements are often found in coating 

regulations and can be defined as the following ratio: 

Amount of solids adhering to substrate 

TE = -------------------------------------- 

Total amount of solids used 

As the TE for a coating operation increases, the total amount of coating used should decrease, and thus, less volatile organic compounds (VOCS) should be emitted into the 

atmosphere. This is a very simple concept; however, the implementation and measurement of TE requirements has lead to many problematic situations. 

EPA's guidance document, Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations (a.k.a. the "Blu--book"), contains a discussion on TE. Most of the TE 

issues found in the Bluebook concern district rules which allowed sources to generate emissions credits by changing application equipment. In the past, TE emissions credits 

were used to bring sources into compliance. Unfortunately, the credits were often based upon invalid baseline TE's and table value TE's (e.g., NSPS table values) which were 

not appropriate. In order to receive credit for using a more transfer efficient process, a source must use the correct baseline TE and a valid test method to determine the actual 

TE for the more transfer efficient process, and the criteria for determining the baseline and test method must be 

specified by the rule. 

The main problem in determining the actual TE for a coating rule is that there are currently no EPA approved TE test methods except for Automobile and Light-Duty Truck Manufacturin g facilities. TE Test methods 

must be custom designed for the 

situation that is being tested and must consider all the parameters of the operation (e.g., substrate size, substrate shape, application equipment, etc.). A change in any of the 

operation's parameters can invalidate the TE determined by a method. Past efforts have attempted to assign specific TE percentages to different types of application 

equipment based upon test results performed on panels. However, results from such tests could rarely be used due to the vast variety of shapes, sizes and other operating 

conditions found from facility to facility. - 

Because of all the problems associated with TE requirements and developing TE test methods, the California Technical Review Group (TRG) created a sub-committee to study 

the problem and recommend some solutions. Based upon the TRG recommendation (January 30, 1989 letter from Eric P. Skelton to APCO's),,many recent regulations simply 

specify the type of application equipment that must 

33 

 be used and no longer require a TE percentage. However, there is 

often still a TE percentage requirement for equipment other than 

the specified equipment. 

The following examples of language extracted from both actual and proposed regulations are directly associated with some of the issues discussed above. Each of the 

examples are followed by a brief discussion of problems found with the example and potential remedies. (It should also be noted that the invalid TE credits were generated for 

rules which were silent concerning TE requirements, and thus, there are no such examples presented below.) 

Example

1. Requiring that unspecified application equipment is 65% transfer efficient based upon approved procedures. 

Unapprovable provision: 

"Transfer Efficiency 

On or after January 1, 1991, a person or facility shall not apply coatings unless the coating is applied with properly operating equipment, according to operating 

procedure specified by the equipment manufacturer or the Deputy Executive Officer/Operations, and by the use of one of the following methods: 

(A) Electrostatic application, or 

(B) Flow coater, or 

(C) Roll coater, or 

(D) Dip coater, or 

(E) High-Volume Low-Pressure (HVLP) spray, or 

(F) Hand Application Methods, or 

(G) Such other.alternative application methods as are demonstrated to the Deputy ExecL,-tive Officer/operations, using District approved procedures to be capable of 
achieving at least 65 percent transfer efficiency and for which written approval of the Deputy Executive Officer/Operations has been obtained." 

This provision is unapprovable for the following reasons: 

(1) It allows Executive Officer approval without EPA approval. 

(2) It contains a 65% requirement based upon district procedures which have never been evaluated or approved by EPA. 

Approvable provision(s): 

There are three possible fixes for this provision: - 

1. Remove section (G) and amend the rule as new high transfer efficiency processes are presented and verified to the district. 

34 

 2. Require the source to get EPA approval as well as the 

Deputy Executive Officer/Operations, approval in section 

(G).

3. Include a reference to an EPA approvable district test method. Thus, section (G) might include the following language: 11... Such other alternative application 

methods which have been demonstrated to-be achieving at least 65 percent transfer efficiency using District Procedure XX.I. 

With this language, the district mus@.also submit District Procedure XX and the approvability of this portion of the rule would depend on EPA's evaluation of District Procedure 

XX. 

35 

VOC DefinitiOn

EPA's guidance document, Issues Relating to VOC Regulation Cutpoints, Deficiencies, and Deviations (a.k.a. the "Bluebook") provides a model VOC definition. Since the 

publication of the Bluebook (May 25, 1988), four additional compounds have been added to the list of exempt compounds. Thus, the following compounds are considered nonreactive by EPA and are not controlled as VOCS: 

-1. Methan@ 

'2. Ethane' 

3. Methyl Chloroform (111,1-Trichlororethane) 

4. Trichlorotrifluoroethane (CFC-113) 

5. Methylene Chloride 

6. Trichlorofluoromethane (CFC-11) 

7. Dichlorodifluoromethane (CFC-lz) 

-8. Chlorodifluororethane (CFC-22) 

9. Trifluoromethane (CFC-23) 

10. Dichlorotetrafluoroethane (CF-114) 

11. Chloropentafluoroethane (CFC-115) 

12. Dichlorotrifluoroethane (HCFC-123) 

13. Tetrafluoroethane (HFC-134a) 

14. Dichlorofluoroethane (HCFC-141b) 

15. Chlorodifluoroethane (HCFC-142b) 

The last four compounds (12-15) in the above list have been added to the list since the publication of the Blue Book. Many districts have exempted these compounds in their 

definition of VOCS. However, some distriqts want to control compounds that are considered exempt or non-reactive by EPA and have not specfically exempted all the above 

compounds from their VOC definition. EPA finds this more stringent approach acceptable as long as the districts do not claim the control of these compounds as emission 

reductions in their Ozone State Implementation Plans (SIP), as credits under the Emissions Trading Policy, or for determining compliance with emission limits. 

-------------------- 

3. The California Air Resources Board considers ethane as a reactive VOC and will not approve rules which exempt ethane. EPA will accept a VOC definition 

which does not exempt ethane if emission reduction credits associated with the control of ethane are not claimed-in the district's ozone SIP. 

36 

Examples

1. Examples of VOC definitions with specified exempt compounds. 

Approvable definition: 

Any organic compound which participates in atmospheric photochemical reactions. This includes any organic compound other than the following compounds: 

methane, ethane, methylene chloride, methyl chloroform (1,1,1trichloroethane), CFC-113 (trichlorotrifluoroethane), CFC-11 (trichlorofluoromethane), CFC-12 

(dichlorodifluoromethane), CFC-22 (chlorodifluoromethane), CFC-23 (trifluoromethane), CFC-114 (dichlorotetrafluoroethane), CFC-115 (chloropentafluoroethane), 

HCFC-123 (dichlorotrifluoroethane), HFC134a (tetrafluoroethane), HCFC-141b (dichlorofluoroethane), and HCFC-142b (chlorodifluoroethane). These compounds 
have been determined to have negligible photochemical reactivity. For purposes of determining compliance with emission limits, VOC will be measured by the 

approved test methods. Where such a method also inadvertently measures compounds with negligible photochemical reactivity, an owner or operator may exclude 

these negligibly reactive compounds when determining compliance with an emissions standard. 

This definition is based upon the model definition found in EPA's 

Bluebook. 

Unapprovable definition: 

"Volatile Organic Compound: Any organic compound (excluding methane, carbon monoxide, carbon dioxide, carbonic acid A metallic carbides or carbonates and 

ammonium carbonate) which would be emitted during use, application, curing or drying of a solvent or surface coating. For the purpose of calculating the VOC content 

of a coating, any water or the following non-precursor organic compounds shall not be considered to be part of the coating: 

methylene chloride 

1,1,1-trichloroethane 

trichlorofluoromethane (CFC-11)

dichlorodifluoromethane (CFC-12)

trichlorotrifluoroethane (CFC-113)

dichlorotetrafluoroethane (CFC-114)

chloropentafluoroethane (CFC-115)"

-------------------- 

4. These compounds are not specifically exempted by EPA as they are considered inorganic compounds; however, district VOC definitions which specifically exempt 

these compounds will not be unapprovable based upon this exemption. 

37 

 This definition is unapprovable because is not consistent with EPA's VOC definition and list of non-'reactive compounds; however, it would be approvable if the district did not 

claim any emission reduction credits resulting from the decreased use of exempt compounds which are not listed above, but are considered exempt by EPA. 

Approvable definition: 

Volatile Organic Compound: Any organic compound which would be emitted during use, application, curing or drying of a solvent or surface coating. For the purpose of 

calculating the VOC content of a coating, any water or the following non-precursor organic compounds shall not be considered to be part of the coating. However, the 

District will not claim emission reduction credits from the control of any compound determined to be negligably phutochemically reactive by EPA: 

methylene chloride 

1,1,1-trichloroethane 

trichlorofluoromethane (CFC-11)

dichlorodifluoromethane (CFC-12) 

trichlorotrifluoroethane (CFC-113)

dichlorotetrafluoroethane (CFC-114) 

chloropentafluoroethane (CFC-115) 

2. VOC definition exempting compounds not specifically exempted 

per EPA's VOC definition. 

Unapprovable provision: 

"PHOTOCHEMICALLY REACTIVE SOLVENT means any solvent with an aggregate or more than 20 percent of its total volume composed of the chemical compounds 

classified below or which exceeds any of the following individual percentage composition limitations, referred to the total volume of solvent: 

(a) A combination of hydrocarbons, alcohols, aldehydes, ethers esters or ketones having an olefinic or cycloolefinic type of unsaturation except 

perchloroethylene: 5 percent; 

(b) A combination of aromatic compounds with eight or more carbon atoms to the molecule except ethylbenzene, 

methyl benzoate and phenyl acetate: 8 percent; 

(c) A combination of ethylbenzene, ketones having branched hydrocarbon structures, trichloroethylene or toluene: 

20 percent. 

Whenever any organic solvent or any constituent of an organic solvent may be classified from its chemical structure into more than one of the above groups of organic 

compounds, it shall be considered as a member of the most reactive chemical group, that is, that group having the least allowable percent of the total volume of 

solvents." 
38 

 The exemption of perchloroethylene as a photochemically reactive solvent is inconsistent with EPA's VOC definition. Furthermore, this definition potentially allows a source to 

dilute a solvent to a point where the solvent may no longer be considered photochemically reactive. There is no easy way to fix this definition. EPA would recommend that this 

definition be replaced with one of the VOC definitions found in Example 1 above. 

3. VOC definition based upon vapor pressure. 

Unapprovable definition: 

Volatile Organic Compound (VOC). VOC means any organic compound (excluding methane, carbon monoxide, carbon dioxide, carbonic acid, metallic carbides or 

carbonates and ammonium carbonate) that has a vapor pressure greater than 0.1 mm of Hg at standard conditions. 

EPA's Bluebook states specifically that use of a vapor pressure cutoff to define VOC is inconsistent with EPA reactivity policy. Such a definition would exempt compounds of low 

volatility which, under certain conditions, would volatilize and, therefore, would participate in photochemical reactions. Again, EPA would recommend that this definition be replaced 

with one of the VOC definitions found in Example 1 above. 

39 

 APPENDIX A 

LIST OF ALL CTG CATEGORIES 

 Existing CTGS: 

1. Design criteria for Stage I Vapor Control Systems, Gasoline Service Stations, U.S. EPA, OAQPS, November 1975. 

Control Methods for Surface Coating Operations (EPA450/2-76-028). 

Surface Coatings of Cans, Coils, Paper, Fabric, Automobiles and Light-Duty Trucks (EPA-450/2-77-008). 

4. Solvent Metal Cleaning/Degreasing Operations (EPA450/2-77-022). 

5. Refinery Vacuum Producing Systems, Wastewater Separators and Process Unit Turnarounds (EPA-450/2-77- 

025). 

6. Hydrocarbons from Tank Truck Gasoline Loading Terminals (EPA-450/2-77-026). 

.:7@ Surface Coatings of Metal Furniture (EPA-450/2-77-032). 

Surface Coatings of Insulation of Magnetic Wire (EPA450/2-77-033). 

Surface Coatings of Large Appliances (EPA-450/2-77-034). 

10. Bulk Gasoline Plants (EPA-450/2-77-035). 

11. Storage of Petroleum Liquids in Fixed Roof Tanks (EPA450/2-77-036). 

12. Use of Cutback Asphalt (EPA-450/2-77-037). 

Surface Coating of Miscellaneous Metal Parts and Products (EPA-450/2-78-015). 

14. Stationary Sources (EPA-450/2-78-022). 

15. Manufacture of Synthesized Pharmaceutical Products (EPA-450/2-78-029) - 

16. Manufacture of Pneumatic Rubber Tires (EPA-450/2-78- 

030). 

@l . Factory Surface Coating of Flat Wood Paneling (EPA4 50/2-78-032) . 

18. Graphic Arts - Rotogravure and Flexography (EPA-450/278-033). 

19. Leaks from Petroleum Refinery Equipment (EPA-450/2-78- 

036). 

20. Petroleum Liquid Storage in External Floating Roof Tanks (EPA-450/2-78-047). 

21. Perchloroethylene Dry Cleaning Systems (EPA-450/2-78- 

050). 

22. Leaks from Gasoline Tank Trucks and Vapor Collection Systems (EPA-450/2-78-051). 

23. Vplatile Organic Liquid Storage in Floating and Fixed Roof Tanks, DRAFT, August 1981. 

24. Large Petroleum Dry Cleaners (EPA-450/3-82-009). 

25. Fugitive Emission Sources (EPA-450/3-82-010). 

26. Synthetic Organic Chemical Polymer and Resin Manufacturing Equipment (EPA-450/3-83-006). 

27. Equipment Leaks from Natural Gas/Gasoline Processing Plants (EPA-450/2-83-007). 

28. Manufacture of High-Density Polyethylene, 

Polypropylene, and Polystyrene Resins (EPA-450/3-83- 

008). . 

29. Synthetic Organic chemical Manufacturing Industry (SOCMI) (EPA-450/3-84-015). 

 

CTGs in progress: 
l@ Adhesives 

2. Aerospace 

3. Autobody Refinishing 

4. Clean-up Solvents 

5. Consumer Products 

6. Marine Vessel Building and Repair 

7. Marine Vessel Loading and Unloading 

8. Petroleum and Industrial Wastewater 

9. Plastic Parts (Coatings-Business Machines) 

10 .Plastic Parts (Coatings-Other) 

ii. SOCMI Batch Processes 

12. SOCMI Distillation Operations 

13. SOCMI Reactor Processes 

14. Treatment, Storage & Disposal Facilities 

15. Web Offset Lithography 

 APPENDIX B 

CAPTURE EFFICIENCY MODEL RULE