# Control Techniques Guidelines for

Miscellaneous Industrial AdhesivesThis page intentionally left blankEPA-453/R-08-005 September 2008



# Control Techniques Guidelines for

Miscellaneous Industrial Adhesives

U.S. Environmental Protection Agency Office of Air Quality Planning and Standards Sector Policies and Programs Division Research Triangle Park, NCThis page intentionally left blanki 

### TABLE OF CONTENTS

I. Introduction....................................

................................................... ...................................... 1 II. Background and Overview ........................

................................................... .......................... 2 III. Applicability .................................

................................................... ................................... 3 IV. Process Description and Sources of VOC Emission s.................................................. ....... 4 A. Process Description.............................

................................................... ............................. 5 1. Surface Preparation.............................

................................................... ......................... 5 2. Adhesive Application............................

................................................... ....................... 5 3. Cleaning Activities.............................

................................................... .......................... 7

B. Sources of VOC Emissions........................

................................................... ...................... 7

1. Adhesives.......................................

................................................... .............................. 8 2. Cleaning Materials..............................

................................................... ......................... 8 V. Available Controls and Regulatory Approaches....

................................................... .............. 9

A. Available Controls for VOC Emissions from Adhesi ves ................................................ ... 9

1. Pollution Prevention Measures ...................

................................................... ................. 9 2. Emission Capture and Add-on Control Systems .....

................................................... .. 10

B. Available Controls for VOC Emissions from Cleani ng Materials ................................... 13

1. Product Substitution/Reformulation ..............

................................................... ............ 13

2. Work Practice Procedures........................

................................................... .................. 13 C. Existing Federal, State, and Local Recommendatio ns or Regulations ............................. 14 1. Existing State and Local VOC Requirements.......

................................................... ..... 14 VI. Recommended Control Options....................

................................................... ................. 15

A. Adhesive and Adhesive Primer Emission Limits ....

................................................... ...... 17 B. Adhesive Application Methods....................

................................................... .................. 19 C. Add-on Controls for Adhesive Application Operati ons ................................................ ... 19

D. Work Practices for Adhesive-Related Activities ..

................................................... ......... 19 E. Work Practices for Cleaning Materials...........

................................................... ............... 20 VII. Cost Effectiveness of Recommended Control Opti ons ................................................ .... 20

VIII. References...................................

................................................... ................................... 21



### LIST OF APPENDICES

Appendix A - Definitions Appendix B - Summary of State and Local Requirement s for VOC Emissions from Adhesives

and Adhesive Primers Appendix C - Summary of State and Local Requirement s for Application Method and

Efficiencyii This page intentionally left blank.1

I. Introduction

Clean Air Act (CAA) section 172(c)( 1) provides tha t state implementation plans (SIPs) for nonattainment areas must include “reasonably av ailable control measures” (RACM), including “reasonably available control technology” (RACT), for sources of emissions. Section 182(b)(2)(A) provides that for certain nonattainmen t areas, States must revise their SIPs to include RACT for each category of volatile organic compound (VOC) sources covered by a control techniques guidelines (CTG) document issued between November 15, 1990 and the date

of attainment.

The United States Environmental Protection Agency ( EPA) defines RACT as “the lowest emission limitation that a particular source is cap able of meeting by the application of control technology that is reasonably available considering technological and economic feasibility.” 44 FR 53761 (September 17, 1979). In subsequent Feder al Register notices, EPA has addressed how States can meet the RACT requirements of the CA A.

Clean Air Act section 183(e) directs EPA to list fo r regulation those categories of products that account for at least 80 percent of th e VOC emissions, on a reactivity-adjusted basis, from consumer and commercial products in areas that violate the NAAQS for ozone (i.e., ozone nonattainment areas). EPA issued the list on March 23, 1995, and has revised the list periodically. See 60 FR 15264 (March 23, 1995); se e also 71 FR 28320 (May 16, 2006), 70 FR 69759 (Nov. 17, 2005); 64 FR 13422 (March 18, 1999 ). Miscellaneous Industrial Adhesives are included on the current section 183(e) list.

This CTG is intended to provide State and local air pollution control authorities information that should assist them in determining RACT for VOCs from miscellaneous industrial adhesive application processes. In deve loping this CTG, EPA, among other things,

evaluated the sources of VOC emissions from miscell aneous industrial adhesives application processes and the available control approaches for addressing these emissions, including the costs of such approaches. Based on available infor mation and data, EPA provides

recommendations for RACT for miscellaneous industri al adhesives.

States can use the recommendations in this CTG to i nform their own determination as to

what constitutes RACT for VOCs for miscellaneous in dustrial adhesive application processes in their particular nonattainment areas. The informat ion contained in this document is provided only as guidance. This guidance does not change, o r substitute for, requirements specified in applicable sections of the CAA or EPA’s regulations ; nor is it a regulation itself. This document does not impose any legally binding requirements on any entity. It provides only recommendations for State and local air pollution c ontrol agencies to consider in determining RACT. State and local pollution control agencies a re free to implement other technically-sound approaches that are consistent with the CAA and EPA ’s implementing regulations.

The recommendations contained in this CTG are based on data and information currently available to EPA. These general recommendations ma y not apply to a particular situation based upon the circumstances of a specific source. Regar dless of whether a State chooses to implement the recommendations contained herein through State rules, or to issue State rules that adopt2

different approaches for RACT for VOCs from miscell aneous industrial adhesives, States must submit their RACT rules to EPA for review and appro val as part of the SIP process.

EPA will evaluate the rules and determine, through notice and comment rulemaking in the SIP approval process, whether the submitted rul es meet the RACT requirements of the CAA and EPA’s regulations. To the extent a State adopt s any of the recommendations in this guidance into its State RACT rules, interested part ies can raise questions and objections about the substance of this guidance and the appropriaten ess of the application of this guidance to a particular situation during the development of the State rules and EPA’s SIP approval process.

Clean Air Act section 182(b)(2) requires that a CTG issued between November 15, 1990, and the date of attainment include the date by whic h States subject to section 182(b) must submit SIP revisions in response to the CTG. Accordingly, EPA is providing in this CTG a one-year period for the required submittal. Pursuant to sec tion 182(b)(2), States required to submit rules consistent with section 182(b) must submit their SI P revisions within one year of the date of

issuance of the final CTG for miscellaneous industr ial adhesives.

II. Background and Overview

There are no previous EPA actions that affect misce llaneous industrial adhesive application operations.

In 1998, the California Air Resources Board (ARB) i ssued a guidance document that includes ARB’s determination of Reasonably Availabl e Control Technology (RACT) and Best Available Retrofit Control Technology (BARCT) for A dhesives and Sealants 1 . The 1998 ARB document presented RACT and BARCT for controlling V OC emissions from the commercial and industrial application of adhesives and sealant s. The ARB RACT determination prescribes

VOC emission limits for various industrial adhesive s and sealants and was developed based on eight existing California air pollution control dis trict rules for adhesives and sealants that were in effect in 1998. Those eight districts included Bay Area (BAAQMD), El Dorado County (EDCAPCD), Placer County (PCAPCD), Sacramento Metro politan (SMAQMD), South Coast (SCAQMD), Ventura County (VCAPCD), Yolo-Solano (YSA QMD), and San Diego County (SDCAPCD).

Since the development of the ARB RACT determination , five additional California air pollution control districts have adopted rules base d on the ARB RACT standards, resulting in a total of 13 air pollution control districts in Cali fornia having established rules for adhesives.

In 2007, the Ozone Transport Commission issued its Model Rule for Adhesives and

Sealants. 2 The model rule was based almost entirely on the 19 98 California ARB RACT determination. The model rule is designed for adop tion by member states in 2009. To date, only Maryland has adopted an adhesives rule based on the OTC model rule. Connecticut, Delaware, District of Columbia, Maine, Massachusetts, New Ham pshire, New Jersey, New York, Pennsylvania, Rhode Island, Vermont, and Virginia a re all either currently in various stages of formal rule adoption or are developing a proposed r ule.

At least eight California Districts and Maryland re gulate cleaning materials used in adhesive application processes. These regulations require a combination of work practice, equipment standards, and limits on the VOC content, boiling point, or composite vapor pressure3

of the solvent. Some California District rules all ow the use of add-on controls as an alternative to the VOC content/boiling point/vapor pressure lim its for cleaning materials.

EPA developed the recommended approaches contained in this document after reviewing the existing State and local VOC emission reduction approaches.

The remainder of this document is divided into six sections. Section III describes the scope of sources to which the control recommendatio ns in this CTG could apply. Section IV describes the miscellaneous industrial adhesives, i ncluding the types of adhesive materials and the application processes, and identifies the sourc es of VOC emissions from those processes. Section V describes the available control approache s for addressing VOC emissions from this product category and summarizes State and local app roaches for addressing such emissions. Section VI provides our recommendations for RACT fo r miscellaneous industrial adhesives application processes. Section VII discusses the c ost-effectiveness of the recommended control approaches. Section VIII contains a list of refere nces.

III. Applicability

This CTG provides control recommendations for reduc ing VOC emissions from miscellaneous industrial adhesives and adhesive pri mer application processes. Please see section IV of this CTG for a description of the miscellaneo us industrial adhesives category under section 183(e) of the CAA. This section addresses EPA's re commendations as to the scope of entities to

which the RACT recommendations in this CTG should a pply. As explained above, this document is a guidance document and provides inform ation for States to consider in determining RACT. When State and local pollution control agenc ies develop RACT rules, they may elect to adopt control approaches that differ from those des cribed in this document and/or promulgate applicability criteria that differ from those recom mended here.

In terms of applicability, we recommend that the co ntrol approaches discussed in section VI of this CTG apply to each miscellaneous industri al adhesive application process 1 at a facility

where the total actual VOC emissions from all misce llaneous industrial adhesive application processes, including related cleaning activities, a t that facility are equal to or exceed 6.8 kg/day (15 lb/day), or an equivalent level such as 3 tons per 12-month rolling period, before

consideration of controls. We do not recommend the se control approaches for facilities that emit below this level because of the very small VOC emis sion reductions that can be achieved. The recommended threshold level is equivalent to the ev aporation of approximately two gallons of solvent per day. Such a level is considered to be an incidental level of solvent usage that could be expected even in facilities that use very low-so lvent adhesives, such as radiation cured adhesives (these adhesives will be discussed in mor e detail in section IV.B.1 of this document). Furthermore, based on the 2002 NEI data and the 200 4 ozone nonattainment designations, facilities emitting below the recommended threshold level collectively emit less than 6 percent of the total reported VOC emissions from miscellaneous industrial adhesive application processes in ozone nonattainment areas. For these reasons, w e did not extend our recommendations in this CTG to these low-emitting facilities. For purposes of determining whether a facility meets our

1 An application process consists of a series of one or more adhesive applicators and any associated dr ying area and/or oven wherein an adhesive is applied, dried, and/or cured. An application process ends at the p oint where the adhesive is dried or cured, or prior to any subsequ ent application of a different adhesive. It is not necessary for an application process to have an oven or flash-off ar ea.4

recommended applicability threshold, aggregate emis sions, before consideration of control, from all miscellaneous industrial adhesive application p rocesses (including related cleaning activities) at a given facility are included.

In developing their RACT rules, State and local age ncies should consider carefully the

facts and circumstances of the affected sources in their States. As noted above, States can adopt the above recommended 6.8 kg/day (15 lb/day) actual VOC emissions or an equivalent applicability threshold, or they can develop other applicability criteria that they determine are appropriate considering the facts and circumstances of the sources in their particular

nonattainment areas. EPA will review the State RAC T rules in the context of the SIP revision

process.

The 2002 National Emission Inventory (NEI) was used as the source of emissions data and other information concerning facilities operati ng miscellaneous industrial adhesive application processes.

In developing this CTG, the 2002 NEI database was q ueried for facilities likely performing miscellaneous industrial adhesive applic ation based on Source Classification Code (SCC) 40200701, 40200706, 40200707, 40200710, 40200 711, and 40200712. This activity resulted in 1,048 facilities with miscellaneous ind ustrial adhesive application processes in the 2002 NEI, and VOC emissions totaled an estimated 8, 660 Mg/yr (9,546 tpy) from adhesive application processes. Of the 1,048 facilities ide ntified in the 2002 NEI, 720 facilities were

located in ozone nonattainment areas and 180 of the facilities located in ozone nonattainment areas emit more than the 6.8 kg/day (15 lb/day) VOC applicability threshold described above. These 180 facilities emitted an estimated 4,428 Mg (4,881 tons) of VOC in 2002 from adhesive application processes.

IV. Process Description and Sources of VOC Emission s

The miscellaneous industrial adhesives product cate gory includes adhesives (including adhesive primers used in conjunction with certain t ypes of adhesives) used at industrial manufacturing and repair facilities for a wide vari ety of products and equipment that operate adhesives application processes.

The miscellaneous industrial adhesives product cate gory does not include adhesives that are addressed by CTGs already issued for categories listed under CAA Section 183(e) or by

earlier CTGs. These include the CTGs issued under Section 183(e) for aerospace coatings; metal furniture coatings; large appliance coatings; flat wood paneling coatings; paper, film, and foil coatings; offset lithographic printing and letterpr ess printing; and flexible package printing. Coil coating, fabric coating, and rubber tire manufactur ing were not listed under CAA Section 183(e), however, they were the subject of earlier CTGs whic h address adhesives used in those processes.

Motor vehicle adhesives, glass bonding primers, and weatherstrip adhesives that are used at a facility that is not an automobile or light-du ty truck assembly coatings facility, are addressed

in this CTG for miscellaneous industrial adhesives. Please see section VI of this CTG for our

VOC control recommendations for these motor vehicle materials. The VOC control

recommendations for these motor vehicle materials i n the CTG for miscellaneous industrial

adhesives are the same as the VOC control recommend ations for similar materials used at5

automobile and light-duty truck assembly coating fa cilities, which are addressed in the final automobile and light-duty truck assembly coatings C TG.

A. Process Description

Adhesives are used for joining surfaces in assembly and construction of a large variety of products. Adhesives allow for faster assembly spee ds, less labor input, and more ability for joining dissimilar materials than other fastening m ethods. Although there are a wide variety of adhesives formulated from a multitude of synthetic and natural raw materials, all adhesives can be generally classified as solution/waterborne, sol vent-borne, solventless or solid (e.g., hot melt adhesives), pressure sensitive, hot-melt, or reacti ve (e.g., epoxy adhesives and ultraviolet-curable adhesives). Adhesives can also be generally classi fied according to whether they are structural

or nonstructural. Structural adhesives are commonl y used in industrial assembly processes and are designed to maintain product structural integri ty.

1. Surface Preparation

The vast majority of adhesives require the applicat ion of a primer to the substrate before the adhesive is applied. Adhesive primers are usua lly applied in very thin films, and serve to wet the substrate surface and provide improved bonding capability for the adhesive. Adhesive primers are commonly solvent-borne materials 3

.
2. Adhesive Application

Adhesive application is accomplished by applying an adhesive to a substrate, followed by curing or drying the adhesive. The adhesive itself may be in the form of an aerosol applied by spraying, or liquid applied by spraying, rolling, o r dipping.

There are several different types of applicators th at may be used to apply adhesives, and are generally similar or identical to surface coati ng application techniques. The most common types of applicators include: air atomized spray, e lectrostatic spray, high volume/low pressure (HVLP) spray, dip coating, flow coating, brush or r oll coating, electrocoating, and hand application.

Spray application operations are typically performe d in a spray booth by manual or automated (e.g., robotic) means to capture overspra y, remove solvent vapors from the workplace, and to keep the application operation from being co ntaminated by dirt from other operations. In some instances, productivity is maximized by using automated application followed by manual touchup. Typically, overspray is collected within the booth on either dry filter media or a waterwash booth. Air flow in a booth equipped with dry filter media generally passes from the spray applicator, over the substrate, and through a dry filter bank. Waterwash booths are less commonly used than dry filter booths. In a waterwa sh booth, air is drawn through a continuous curtain of moving water and overspray is removed by contact with the water. In booths equipped with dry filters and in waterwash booths, the overs pray can be collected on a series of baffles in front of the dry filters or waterwash, and, in some cases, the collected overspray can be reused. This recycling method substantially reduces both ai r emissions and waste (including spent dry filters) generated by the adhesive application oper ation.6

Several different types of application technologies are used to apply adhesives, and the selection of the application technology can signifi cantly affect the amount of adhesive used and the resulting VOC emissions from the application pr ocess.

Conventional air spray application uses compressed air at high pressure ( e.g., 30 to 90 pounds per square inch, psi) to pull the adhesive f rom a reservoir and atomize the adhesive as it is expelled from the spray gun tip. The mixture of air and atomized adhesive then deposits the adhesive on the substrate. Because of the high pre ssure of air used, most of the adhesive does not land on the substrate and is carried away from the substrate as overspray and is wasted. The

fraction of adhesive solids that reaches the substr ate is termed transfer efficiency, and conventional air spray has a relatively low transfe r efficiency compared to other application methods. Therefore, many application processes hav e adopted other types of spray application to use adhesives more efficiently.

Airless Spray. With airless spray, a pump forces the adhesive thro ugh an atomizing nozzle at high pressure (1,000 to 6,000 psi). Airl ess spray is ideal for rapid coverage of large areas and when a heavy film build is required. The size of airless spray adhesive droplets is larger, the spray cloud is less turbulent, and the transfer efficiency is typically superior to conventional air spray.

Air-Assisted Airless Spray . An air-assisted airless system combines the bene fits of conventional air spray and airless spray. The syst em consists of an airless spray gun with a compressed air jet at the gun tip to atomize the ad hesive. It uses lower fluid pressures than airless spray and lower air pressures than conventi onal air spray (e.g., 5 to 20 psi versus 30 to 90 psi). This fluid/air pressure combination deliv ers a less turbulent spray than conventional air systems and applies a more uniform finish than airl ess systems. However, the amount of time needed to apply adhesives is greater because of the lower fluid and air pressure.

Electrostatic Spray . In electrostatic spray application, the adhesive and substrate are oppositely charged. The substrate is grounded and attracts the negatively charged adhesive particles. Electrostatic spray systems are reporte d to have the highest transfer efficiency of any of the spray application techniques because of mini mal overspray, which also results in lower

adhesive loss and lower VOC emissions.

HVLP systems use lower air pressures (generally not more than 1 0 psi at the spray cap) and greater volumes than conventional air atomized spray systems. Specialized nozzles provide better air and fluid flow at the lower air pressure , and shape the air/spray pattern and guide the atomized adhesive particles to the substrate. The lower air pressures result in greater transfer efficiency compared to conventional air atomized sp ray systems.

Dip coating

is another available method for applying liquid ad hesives. It is typically used for large complicated parts where it would be difficult to use other methods. The substrates are manually or automatically dipped into a tank co ntaining the adhesive. The substrates are then withdrawn from the tank and any excess adhesiv e is allowed to drain, thus achieving very high transfer efficiencies. Typical systems have s ome means of recirculation of the tank contents, filters to remove paint sediment and soli d contaminants, and means for controlling the viscosity of the fluid. Because the tank opening e xposes a large surface area of liquid adhesive,7

solvent losses occur from the tank. To maintain th e desired adhesive viscosity in the tank, these losses are compensated by adding thinner (water or solvent, depending on the adhesive used).

Flow coating

is similar to dip coating and involves conveying t he substrate over an enclosed sink, where the adhesive is applied at low pressure as the item passes under a series of

nozzles. Excess adhesive drains back into the sink , is filtered, and pumped back into a holding tank. A typical flow coater tank is enclosed and i s smaller than the equivalent dip coating tank. As a result, less adhesive is used and less solvent is evaporated than in dip tank operations. This application method results in an increase in produc tion rate.

Roll coating, brush coating, and hand application are often used for high viscosity adhesives and for application onto small surface ar eas.

Electrocoating (electrodeposition) is a specialized form of dip coating where opposit e electric charges are applied to the waterborne adhe sive and the substrate. The adhesive is deposited on the part by means of electrical attrac tion, which produces a more uniform application on the substrate than traditional dip a pplication.

After each of the adhesive application operations d escribed above, the applied adhesive is usually air dried or cured. For liquid spray and d ip coating operations, the substrate is typically first slowly moved through a flash-off area after t he adhesive is applied. The adhesive is either then allowed a specified drying time to allow tacki fication before bonding, or the substrate is immediately bonded.

3. Cleaning Activities

Cleaning activities other than surface preparation and priming also occur at facilities operating miscellaneous industrial adhesive applica tion processes. Cleaning materials are used during these activities to remove adhesive residue or other unwanted materials from equipment related to application operations, as well as the c leaning of spray guns, transfer lines (e.g., tubing or piping), tanks, and the interior of spray booths . These cleaning materials are typically mixtures of VOC-containing solvents.

B. Sources of VOC Emissions

The VOC emissions from miscellaneous industrial adh esives result from evaporation of the solvents contained in many of the primers, adhe sives and cleaning materials during adhesive application and drying processes, as well as during surface preparation and cleaning processes associated with adhesives application. The primary VOC emissions from miscellaneous industrial adhesives occur during application and f lash-off.

A lesser amount of emissions occur from mixing and as the adhesive dries. Essentially all of the remaining VOC in the organic solvent con tained in the adhesives is emitted during the drying process. The VOC emissions from mixing of a dhesives occur from displacement of

VOC-laden air in containers used to mix adhesives c ontaining solvents (thinners) prior to adhesive application. The displacement of VOC-lade n air can also occur during filling of containers and can be caused by changes in temperat ure, changes in barometric pressure, or agitation during mixing.8

The following discussion describes these primary em ission sources (adhesives and cleaning materials).

1. Adhesives

The VOC emissions from adhesive application occur w hen solvent evaporates from the adhesive as it is being applied to the substrate. The transfer efficiency (the percent of adhesive solids deposited on the substrate) of an applicatio n method affects the amount of VOC emitted during application. The more efficient an applicat ion method is in transferring adhesives to the substrates, the lower the volume of adhesives (and therefore solvents) needed per given amount of production; thus resulting in lower VOC emission s.

Conventional air atomized spray equipment utilizes high atomizing air pressure with typical transfer efficiencies of 25 to 40 percent. The transfer efficiency of a dip coater is very high (approximately 90 percent); however, some VOC is emitted from the liquid coating bath due to its large exposed surface area. For liquid adhesives, electrostatic spray coating is more efficient than conventional air atomized spray, wit h transfer efficiency typically ranging from 60 to 90 percent.

After adhesives are applied by any of the typical a pplication methods, the adhesive is usually allowed a drying period. Immediately after application, a fraction of the solvents in the

adhesives flash-off. The amount of VOC emissions f rom flash-off depends on the type of adhesive used, how quickly the substrate moves thro ugh the flash-off area, and the distance between the application area and the drying area.

In spray application operations, the majority of VO C emissions occur in the spray booth. For liquid spray applications, it is estimated that 65-80 percent of the volatiles are emitted during the application and flash-off operations, and the r emaining 20-35 percent from the drying/curing operation.

The trend in controlling VOC emissions from solvent -borne adhesives is not to control through a specific control technology, but rather t o replace them with low VOC adhesives, some of which can perform as well as solvent-borne adhes ives. Since the late 1970’s, adhesive

formulations that eliminate or reduce the amount of solvent in the formulations have been increasing, thus reducing VOC emissions per unit am ount of adhesive used.

Various types of low solvent adhesive include waterborne, hot-melt, solventless twocomponent, and radiation-cured adhesives. Hot-melt adhesives are the most widely used of these alternative processes.

2. Cleaning Materials

Cleaning materials are another source of VOC emitte d by miscellaneous industrial adhesive application processes. The VOC are emitte d when solvents evaporate from the cleaning materials during use.

Cleaning materials with low-VOC composite vapor pre ssure and/or low-VOC content generate less VOC emissions than materials with hig her VOC vapor pressure and/or content. The VOC composite vapor pressure of a cleaning mate rial is a weighted average of the vapor9

pressures of the VOC components of that cleaning ma terial. The vapor pressure of each VOC component is weighted by the mole fraction of that VOC component in the whole cleaning material, including non-VOC components such as wate r or exempt compounds. 2 Water and exempt compounds thereby reduce the VOC composite v apor pressure of cleaning materials in which they are present.

Although use of lower vapor pressure cleaning mater ials may reduce VOC emissions, these materials may not be feasible with the broad range of adhesives used in miscellaneous industrial adhesive application processes. Similar ly, cleaning materials with low VOC content would generate less VOC emissions than materials wi th high VOC content, but may not be feasible with the broad range of adhesives used in miscellaneous industrial adhesive application

processes.

V. Available Controls and Regulatory Approaches

As previously mentioned, there are two main sources of VOC emissions from miscellaneous industrial adhesive application proce sses: (1) evaporation of VOC from the adhesives and adhesive primers; and (2) evaporation of VOC from the cleaning materials. This section summarizes the available control options fo r reducing these VOC emissions and existing State, and local VOC recommendations or requirement s that address these emissions.

A. Available Controls for VOC Emissions from Adhesi ves

There are two general emission control techniques f or reducing VOC emissions from miscellaneous industrial adhesive application proce sses: pollution prevention measures, and emission capture and add-on control systems. Pollu tion prevention is the most prevalent control technique being used by facilities operating miscel laneous industrial adhesive application processes. Add-on control systems are available to industry, but few facilities utilize this control technique. Provided below is a summary of these co ntrol techniques.

1. Pollution Prevention Measures

Pollution prevention measures that are applicable t o miscellaneous industrial adhesive application processes, including product substituti on/reformulation, work practice procedures, and equipment substitution, may be used to decrease VOC emissions from adhesive application operations. Lower VOC content adhesives, higher so lids adhesives and waterborne adhesives, may be used to reduce VOC emissions by reducing or eliminating the organic solvent present in the adhesive. Work practice procedures may also re sult in VOC emission reductions during the application process by reducing waste. The use of efficient application equipment can reduce VOC emission by increasing the adhesive transfer ef ficiency (i.e., the percentage of adhesive solids used that is deposited onto the substrate) a nd reducing the amount of adhesive used and wasted as overspray.

2 Exempt compounds are those classified by EPA as ha ving negligible photochemical reactivity as listed in 40 CFR 51.100(s). Exempt compounds are not considered to be VOC.10

Product Substitution/Reformulation

One pollution prevention measure is to substitute h igher-solvent adhesives with adhesives containing little or no solvents. As previously di scussed, these adhesives include waterborne adhesives, higher solids adhesives, and reactive ad hesives. Manufacturers have developed and are continuing to develop waterborne and reactive f ormulations that replace conventional organic solvent-borne adhesives. These adhesives are gener ally available. Conversion to waterborne adhesives (for example) can lower VOC emissions gre atly, and many miscellaneous industrial adhesive application processes are capable of conve rting to these adhesives. However, the currently available low-VOC adhesives or adhesives with no solvents do not meet the performance requirements of some industrial manufac turing applications and therefore are not viable options for these operations.

Work Practices

Work practice procedures are physical actions inten ded to affect emission reductions. Because work practice procedures are specifically t ailored to an industry, they may vary from a few manual operations to a complex program.

Waste is generated during adhesive material prepara tion, application, and equipment cleaning. If waste is reduced, overall VOC emissio ns from application processes will be reduced

because less VOC adhesive material will be needed f or production. Adhesive waste may be reduced by effectively controlling material prepara tion, maximizing the amount of adhesive transferred to the substrate through the use of app lication methods with higher transfer efficiencies and improved spray technique, and usin g proper equipment maintenance procedures.

Equipment Substitution

The use of the more effective application equipment also reduces VOC emissions. Conventional air atomized spray application systems utilize high atomizing air pressure with typical transfer efficiencies of 25 to 40 percent.

More modern technologies, such electrostatic and HV LP spray equipment, can achieve much higher transfer efficiencies. The increase in transfer efficiency translates to a decrease in usage of materials containing VOC.

In electrostatic spraying, the adhesive is charged and the substrate is grounded, thereby attracting the atomized adhesive to the substrate. Transfer efficiencies of up to 90 percent may be achieved depending on the product shape, size, a nd substrate.

HVLP systems use reduced air pressure to atomize ad hesives and the reduced air reduces turbulence at the part surface and increases transf er efficiency. HVLP spray systems can achieve transfer efficiencies of up to 65 percent u nder optimal conditions of part size and shape, and with good operator technique.

2. Emission Capture and Add-on Control Systems

In addition to pollution prevention measures, VOC e missions from miscellaneous industrial adhesive application processes can be re duced by the use of capture systems, in11

conjunction with add-on control systems that either destroy or recover the VOC in the exhaust streams. As stated previously, although capture sy stems and add-on control devices are available to facilities operating miscellaneous industrial ad hesive application processes, they are generally not used when low VOC adhesives and alternative app lication methods can be used to reduce VOC emissions. The majority of VOC emissions from miscellaneous industrial adhesive application processes occur in the spray booth. Sp ray booths typically exhaust a high volume of air to dilute the concentration of VOC for safety r easons to reduce potential worker exposure to solvent vapors and to reduce the flammability of th e air-vapor mixture. Although VOC emissions in spray booth exhaust can be controlled with add-on controls, it is generally not cost effective to do so because of the large volume of a ir that must be treated and the low

concentration of VOC.

Capture Systems

Capture systems, such as hoods and enclosures, coll ect solvent-laden air from process vents (e.g., spray booth vents) and/or fugitive emi ssions (e.g., flash-off area) and direct the captured air to a control device. The majority of VOC emissions from miscellaneous industrial adhesive application processes occur in the spray b ooth. These emissions can be ducted from the spray booth directly to the control device. In add ition, hoods, floor air sweeps or enclosures can be used to collect fugitive emissions from solvents that evaporate in flash-off areas and route

them to a control device.

The design of the capture system can greatly contri bute to the overall VOC control efficiency. An efficient capture system maximizes the capture of emissions and minimizes the capture of dilution air. Spray booth design and ai r management can reduce the volume of

exhaust air and maximize the VOC concentration of t he exhaust air which can reduce the cost of control. Facilities may combine several captured V OC-laden streams and duct them to a single

control device Add-on Control Systems Add-on controls reduce the amount of VOC emissions by either destruction or recovery with or without recy cling of VOC emission in the exhaust streams. Two categories of add-on control devices can be use d by miscellaneous industrial adhesive application facilities: combustion (thermal or cata lytic oxidation) and recovery (adsorption and absorption). While many control devices can be use d to reduce VOC emissions, the following summary covers those control devices known to be us ed with adhesive application processes: oxidation, adsorption, and absorption. In addition , there are other control measures known to reduce VOC emissions, but are not currently being w idely used in facilities operating miscellaneous industrial adhesive application proce sses. These alternative control technologies

are also discussed below.

Oxidation destroys VOC emissions in an exhaust stream by exp osing the stream to an oxidizing atmosphere at high temperatures. Oxidize rs may be of thermal or catalytic design and combust VOC-containing exhaust streams. Catalytic oxidizers are similar to thermal oxidizers but employ a catalyst to aid in the oxidation react ion. As a result, catalytic oxidizers operate at lower combustion temperatures relative to that requ ired in thermal oxidizers. Both types of oxidizers generally utilize either regenerative or recuperative techniques to preheat inlet gas in order to decrease energy costs associated with high oxidation temperatures. They may also use primary or secondary heat recovery to reduce energy consumption. In general, oxidizers may achieve destruction efficiencies of greater than 95 percent as applied to adhesive application operations with high and constant concentrations of VOC.12

Adsorption occurs when the unbalanced molecular forces on the surface of solids (the adsorbant) attract and retain gases and particulate matter that come in contact with the solid. Several materials are widely used as the adsorbent, such as activated carbon, organic resin polymer, and inorganic materials. Each has substan tial surface area per unit volume. Carbon adsorbers are most commonly used in adhesive applic ation processes.

In a carbon adsorber, activated carbon is used as t he adsorbent in a regenerable fixed bed. In a typical carbon adsorber, VOC-laden air is pass ed through a fixed bed of granular activated carbon. Adsorber beds are typically operated in pa rallel to avoid interruption of VOC control. In this arrangement, when the adsorption capacity o f one bed is exhausted, it can be removed from service and a second adsorber bed can be put i nto service, ensuring that a control device is operating at all times. The spent carbon bed in th e first adsorber bed is then regenerated and can be put into service again.

Carbon adsorption systems can achieve control devic e efficiencies greater than 95 percent. In contrast to combustion, carbon adsorpt ion does not destroy the VOC it removes from

the air stream. Carbon adsorbers used in miscellan eous industrial adhesive application processes are thermally regenerated, usually by passing steam through the carbon beds. The VOC are removed from the carbon (desorbed) and transferred to the steam. The VOC-containing steam is then condensed, and the VOC solvent is separated fr om the water. The recovered solvent can then be decanted for sale or reuse. Regeneration c an also be achieved with hot air. Hot-air regeneration can be quite attractive when dealing w ith water soluble solvents. Carbon adsorption is most amenable to coatings that use a single solv ent; if solvent mixtures are collected by adsorbers, they usually are distilled for reuse.

There are two options for disposing recovered solve nts that cannot be reused. The first is to sell the material back to the solvent supplier o r an independent firm that specializes in reclaiming contaminated solvents. The other option is to use the recovered solvent as a fuel in coating ovens or in boilers. However, many coating ovens and boilers are gas-fired and would require burner modifications to burn solvent. Carb on adsorption is generally economically attractive only if the recovered solvent can be reu sed directly.

Carbon adsorbers are most suitable for solvents tha t are immiscible with water, such as toluene and xylene, but are not recommended for wat er-soluble VOC, such as methyl ethyl ketone and methyl isobutyl ketone. In the case whe re a water-soluble VOC is present, the water vapor will be adsorbed and desorbed along with the VOC vapor, and the VOC may require subsequent purification if it is to be reused.

The presence of solid particles or polymerizable su bstances in the inlet air stream to a carbon adsorber may require pretreatment of the inl et air. In addition, adsorption is usually used for adhesive application exhaust streams at ambient temperature up to approximately 38°C (100°F). Therefore, cooling and dehumidification m ay also be required as pretreatment in some cases. Adding equipment, such as a dehumidificatio n system, increases the costs associated with the use of a carbon adsorption system.

Absorption is the process by which a gas stream is contacted with a liquid so that one or more of the components of the gas stream will disso lve in the liquid. Water is the most common absorbent, but organic solvents may also be used. Removal efficiency can be enhanced by the13

addition of reactive chemical additives to the abso rbent to increase solubility of the absorbed pollutant or change the equilibrium.

Alternative control technologies, such as condensat ion, biodegradation, and UV oxidation are applicable for control of VOC emissions from ad hesives. However, EPA is not aware of any miscellaneous industrial adhesive application facil ities currently using these types of control technologies.

B. Available Controls for VOC Emissions from Cleani ng Materials

Pollution prevention is the most common emission co ntrol technique for reducing VOC emissions from cleaning materials. The pollution p revention measures applicable to miscellaneous industrial adhesive application proce sses include product substitution or reformulation, and work practice procedures. Clean ing materials with low or no VOC content or low-VOC composite vapor pressure may be used to red uce or eliminate VOC emissions from using these materials. Work practice procedures ma y also reduce VOC emission during cleaning operations by reducing the amount of VOC that can e vaporate due to exposure to air.

No add-on control technologies are being used speci fically for reducing VOC emissions from cleaning operations associated with miscellane ous industrial adhesive application processes. However, if cleaning operations are per formed within a capture system that is ducted to an add-on control system, such as a hood routed to a thermal oxidizer, the VOC emissions from the cleaning operations would be reduced by de struction in the thermal oxidizer.

1. Product Substitution/Reformulation

Reducing the composite VOC vapor pressure or VOC co ntent of the cleaning material used, either by substitution or reformulation, is o ne pollution prevention measure that is used to reduce VOC emissions from cleaning operations. How ever, little information is available regarding the types of low-VOC or VOC-free cleaning materials that could be used in miscellaneous industrial adhesive application proce sses and whether they are feasible for the broad types of adhesives used.

2. Work Practice Procedures

Work practice procedures are commonly used in indus try to reduce VOC emissions from cleaning operations. The following work practice p rocedures are used to reduce VOC emissions from miscellaneous industrial adhesive application processes:

C Cover mixing and storage vessels for VOC-containing cleaning materials, and cleaning waste materials except when adding, removi ng, or mixing contents.

C Use closed containers or pipes to store and convey VOC-containing cleaning and cleaning waste materials.

C Minimize spills of VOC-containing cleaning and clea ning waste materials.

C Minimize VOC emissions during cleaning operations.14

C. Existing Federal, State, and Local Recommendatio ns or Regulations

The following discussion is a summary of State and local regulations that address VOC emissions from miscellaneous industrial adhesive ap plication processes. In addition, Appendices B and C summarize the State and local provisions fo r adhesive VOC content limits and application equipment requirements. There are no pr evious EPA actions that address

miscellaneous industrial adhesives.

1. Existing State and Local VOC Requirements

In 1998, the California Air Resources Board (ARB) i ssued a guidance document that included ARB’s determination of Reasonably Availabl e Control Technology (RACT) and Best Available Retrofit Control Technology (BARCT) for A dhesives and Sealants. This document presented RACT and BARCT for controlling VOC emissi ons from the commercial and industrial application of adhesives and sealants. The ARB RAC T determination prescribes VOC emission

limits for various industrial adhesives and sealant s and was developed based on eight existing California air pollution control district rules for adhesives and sealants that were in effect in 1998. Those eight districts included Bay Area Air Quality Management District (AQMD), El Dorado County Air Pollution Control District (APCD) , Placer County APCD, Sacramento Metropolitan AQMD, South Coast AQMD, Ventura County APCD, Yolo-Solano AQMD, and San Diego County APCD.

The ARB based the majority of its RACT determinatio n on limits already in effect in South Coast AQMD, Bay Area AQMD, and Ventura County APCD, and concluded that the VOC limits for adhesives and sealants presented in its RACT determination were achievable and cost-effective. Furthermore, the ARB stated in its RACT determination that most of the adhesive and sealant products being sold in 1998 were alread y compliant with the VOC limits that were

determined to be RACT.

Since the development of the ARB RACT determination , 5 additional California air pollution control districts have adopted rules base d on the ARB RACT standards.

In 2007, the Ozone Transport Commission issued a Mo del Rule for Adhesives and Sealants. The Model Rule was based almost entirely on the 1998 CARB RACT determination. The Model Rule is for adoption by member states in 2009. To date, only Maryland has adopted

an adhesives rule based on the OTC model rule. Mai ne and New Jersey are either currently considering adopting or are in the process of adopt ing the model rule.

Some states regulate VOC emissions from adhesives a s part of their regulations for specific surface coating operations.

A total of 13 air pollution control districts in Ca lifornia have established rules specifically

for adhesives. The various district adhesives rule s do not all contain the same categories and limits as the ARB RACT guidance. Among these distr icts, the South Coast AQMD has generally adopted the most stringent VOC content li mits for the adhesives categories included in SCAQMD Rule 1168 and in other districts with simila r categories. If add-on controls are used, South Coast Rule 1168 requires that the control sys tem capture at least 80 percent of the VOC

emissions.15

Several California air districts require the use of specific types of high-efficiency adhesive application methods to further reduce VOC emissions. For example, in addition to limiting the VOC contents in the adhesives, South C oast Rule 1168 requires the use of one of the following types of application equipment: electrost atic application; flow coating; dip coating; roll coating; hand application; high-volume, low-pr essure (HVLP) spray; or an alternative method that is demonstrated to be capable of achiev ing a transfer efficiency equal to or better than HVLP spray. Alternative methods must be appro ved by the District based on actual transfer efficiency measurements in a side-by-side compariso n of the alternative method and an HVLP spray gun. At least seven other District’s rules t hat regulate emissions from adhesives are similar to South Coast Rule 1168 in that they also require that sources use methods that achieve high transfer efficiency.

At least eight Districts in California and Maryland regulate cleaning materials used in adhesive application processes. These regulations require a combination of work practice and equipment standards and limits on the VOC content, boiling point, or composite vapor pressure

of the solvent. Some District rules allow the use of add-on controls as an alternative to the VOC content/boiling point/vapor pressure limits for cle aning materials. The work practice and equipment standards that have been adopted by Calif ornia Districts include, for example, using closed containers for storing solvent and solvent c ontaining wipes and rags, using enclosed and automated spray gun washing equipment, and prohibit ing atomized spraying of solvent during spray gun cleaning. However, the cleaning material VOC content/boiling point/vapor pressure limits, overall control efficiency requirements, an d work practices vary by District.

VI. Recommended Control Options

Based on a review of the current State and local re quirements discussed above, we are recommending various options, such as the use of lo w VOC content adhesives, specified application methods and control devices, for contro lling the VOC emissions from the adhesives used by facilities operating miscellaneous industri al adhesive application processes. We are also recommending work practices to further reduce VOC e missions from adhesives as well as to minimize emissions from cleaning materials used in miscellaneous industrial adhesive application processes.

To provide flexibility to facilities, we are recomm ending various options for controlling

VOC emissions from miscellaneous industrial adhesiv es. We recommend specific VOC emission limits based on application processes (i.e ., the types of adhesives and substrates). We recommend two options for achieving the recommended emission limits: (1) through the use of low-VOC content adhesives and specified application methods with good adhesive transfer efficiency; or (2) through the use of a combination of low-VOC adhesives, specified application methods, and add-on controls. As an alternative to the emission limits, we recommend an overall control efficiency of 85 percent. This al ternative provides facilities the operational flexibility to use high efficiency add-on controls instead of low-VOC content adhesives and specified application methods, especially when the use of high VOC adhesives is necessary or desirable for product efficacy. We expect the 85 p ercent control efficiency recommendation to result in VOC emission reduction that is equivalent to or exceed the reduction from our

recommended emission limits. Both the emission lim its and the control efficiency

recommendations reflect what we have concluded to b e reasonably available VOC control16

measures for miscellaneous industrial adhesives bas ed on our review of Maryland’s adhesives rule, the OTC model rule, and the various Californi a air district rules.

As mentioned above, we are recommending the use of adhesive application methods with good adhesives transfer efficiency in conjunction w ith the use of low-VOC content adhesives. Specifically, we recommend the following applicatio n methods: electrostatic spray, HVLP spray, flow coat, roll coat, dip coat (including electrode position), airless spray, air-assisted airless spray, or other coating application method capable of achieving good transfer efficiency.

We are recommending that the VOC emission limits an d 85% control efficiency described above not be applied to the following typ es of adhesives and adhesives primer application processes:

C Adhesives or adhesive primers being tested or evalu ated in any research and development, quality assurance, or analytical labor atory.

C Adhesives or adhesive primers used in the assembly, repair, or manufacture of aerospace or undersea-based weapon systems.

C Adhesives or adhesive primers used in medical equip ment manufacturing operations.

C Cyanoacrylate adhesive application processes.

C Aerosol adhesive and aerosol adhesive primer applic ation processes. 3

C Processes using polyester bonding putties to assemb le fiberglass parts at fiberglass boat manufacturing facilities and at other reinforc ed plastic composite manufacturing facilities.

C Processes using adhesives and adhesive primers that are supplied to the

manufacturer in containers with a net volume of 16 ounces or less, or a net weight of one pound or less.

We recommend, however, that the work practices reco mmended in this CTG be implemented to reduce VOC emissions during these ty pes of adhesives and adhesives primer application processes.

Our recommended emission limits are based on the OT C Model Rule for Adhesives and Sealants. As previously mentioned, the emission li mits in the OTC rule were California ARB RACT standards, which were based on numerous Califo rnia District rules and adopted by other California District rules. Furthermore, the OTC mo del rule is intended for adoption by States. In light of the above, we consider the limits in th e OTC model rule to be representative of what

sources in nonattainment areas nationwide can achie ve technically and economically and have therefore adopted these VOC limits as our recommend ations in the CTG.

3 Aerosol adhesives are regulated under EPA’s VOC Em ission Standards for Consumer Products at 40 CFR 59 subpart C. Aerosol adhesive primers are regulated as “primers” under EPA’s VOC Emission Standards for Aerosol Coatings at 40 CFR 59 subpart E.17

The recommended VOC emission limits can be met by a veraging the VOC content of materials used on a single application unit for eac h day (i.e., daily within-application unit averaging). We do not recommend the use of cross-a pplication unit averaging (i.e., averaging across multiple application units) to meet the VOC emission limits recommended in the CTG. However, we have previously provided guidance on cr oss-line averaging. 4 The guidance is directed to State and local agencies that elect to adopt a discretionary economic incentive program (EIP) and includes guidance on the use of c ross-line averaging.

For cleaning materials, we are recommending work pr actices for use with all three of the control options to reduce VOC emissions. We are no t recommending the application of add-on controls in conjunction with these work practices f or the same reasons stated above for adhesive application. The use of add-on controls to reduce emissions from cleaning operations at miscellaneous industrial adhesive application facil ities would be a costly alternative because the area to be controlled is quite large and a large vo lume of air would be captured and directed to a control device. We are also not recommending the us e of a VOC content or VOC composite vapor pressure limit for cleaning materials. We do not have information available regarding current VOC content or VOC composite vapor pressure usage to determine a RACT limit for cleaning materials used in miscellaneous industrial adhesive application processes.

The following discussion summarizes our specific re commendations, including the recommended VOC emission limits, application method s, add-on controls, and work practices during miscellaneous industrial adhesive applicatio n and related cleaning processes.

A. Adhesive and Adhesive Primer Emission Limits

We are recommending separate sets of emission limit s for general adhesive application processes, specialty adhesive application processes , and adhesive primer application processes.

Provided in Table 1 are the recommended emission li mits expressed in terms of mass of VOC per volume of adhesive or adhesive primer (excluding wa ter and exempt compounds, as applied). We are recommending that all VOC-containing materials used by each miscellaneous industrial adhesive application process be included when deter mining the emission rate of the application

process.

We also recommend that the VOC content of adhesives , other than reactive adhesives, used at facilities operating miscellaneous industri al adhesive application processes be determined using EPA Method 24. We recommend that the procedu re for reactive adhesives in Appendix A of the NESHAP for surface coating of plastic parts (40 CFR part 63, subpart PPPP) be used to

determine the VOC content of reactive adhesives. I n addition, we recommend that manufacturer’s formulation data be accepted as an a lternative to these methods. If there is a disagreement between manufacturer's formulation dat a and the results of a subsequent test, we

recommend that States use the test method results u nless the facility can make a demonstration to

the States' satisfaction that the manufacturer's fo rmulation data are correct.

General adhesive application processes are those pr ocesses that are not specifically identified in Table 1 below as specialty adhesives application processes. Table 1 below includes

4 Improving Air Quality with Economic Incentive Prog rams. U.S. Environmental Protection Agency. Research Triangle Park, NC. EPA-452/R-01-001. Jan uary 2001.18

recommended VOC emission limits for general adhesiv es application processes based on the substrates that are being bonded during these proce sses. For general adhesive application processes using an adhesive to bond dissimilar subs trates, we recommend that the highest VOC emission limit apply. Appendix A contains definiti ons of each of the application processes

identified in Table 1 below.

Table 1. Recommended VOC Emission Limits for Gener al and Specialty Adhesive Application Processes

Recommended VOC Emission Limit 1,2 General Adhesive Application Processes (g/l) (lb/gal)
Reinforced Plastic Composite 200 1.7 Flexible vinyl 250 2.1

Metal 30 0.3 Porous Material (Except Wood) 120 1.0

Rubber 250 2.1

Wood 30 0.3

Other Substrates 250 2.1

Recommended VOC Emission Limit 1 Specialty Adhesive Application Processes (g/l) (lb/gal)

Ceramic Tile Installation 130 1.1

Contact Adhesive 250 2.1

Cove Base Installation 150 1.3 Floor Covering Installation (Indoor) 150 1.3 Floor Covering Installation (Outdoor) 250 2.1 Floor Covering Installation (Perimeter Bonded Sheet Vinyl) 660 5.5 Metal to Urethane/Rubber Molding or Casting 850 7.1

Motor Vehicle Adhesive 250 2.1 Motor Vehicle Weatherstrip Adhesive 750 6.3 Multipurpose Construction 200 1.7 Plastic Solvent Welding (ABS) 400 3.3 Plastic Solvent Welding (Except ABS) 500 4.2 Sheet Rubber Lining Installation 850 7.1 Single-Ply Roof Membrane Installation/Repair (Excep t EPDM) 250 2.1 Structural Glazing 100 0.8 Thin Metal Laminating 780 6.5 Tire Repair 100 0.8 Waterproof Resorcinol Glue 170 1.4

Recommended VOC Emission Limit 1 Adhesive Primer Application Processes (g/l) (lb/gal) Motor Vehicle Glass Bonding Primer 900 7.5 Plastic Solvent Welding Adhesive Primer 650 5.4 Single-Ply Roof Membrane Adhesive Primer 250 2.1

Other Adhesive Primer 250 2.1

1 Emission limits are mass of VOC per volume of adhe sive or adhesive primer excluding water and exempt compounds, as applied.

2 If an adhesive is used to bond dissimilar substrat es together, then the applicable substrate category with the highest VOC emission limit is recommended as the li mit for such application.19

B. Adhesive Application Methods

In addition to the VOC emission limits in Section A , we recommend that one of the following application methods be used in conjunctio n with using low-VOC adhesives or adhesive primers:

C Electrostatic spray.

C HVLP spray.

C Flow coat.

C Roll coat or hand application, including non-spray application methods similar to hand or mechanically powered caulking gun, brush, o r direct hand application.

C Dip coat (including electrodeposition).

C Airless spray.

C Air-assisted airless spray.

C Other adhesive application method capable of achiev ing a transfer efficiency equivalent to or better than that achieved by HVLP spraying.

C. Add-on Controls for Adhesive Application Operati ons

Should product performance requirements or other ne eds dictate the use of higher-VOC

materials than those that would meet the recommende d emission limits, a facility could choose to use add-on control equipment with an overall contro l efficiency of 85 percent. Alternatively, a facility could use a combination of adhesives and a dd-on control equipment on an application unit to meet the recommended mass of VOC per volume of adhesive or adhesive primer limits. Add-on devices include, for example, oxidizers, ads orbers, absorbers, and concentrators. Addon devices coupled with capture systems to collect the VOC being released at the affected facilities can achieve an overall control efficiency of 85 per cent. This control option, like the options noted above, applies to all adhesives and adhesive primers applied in miscellaneous adhesive application processes.

D. Work Practices for Adhesive-Related Activities

In addition to the control options above, this CTG recommends work practices to further

reduce VOC emissions from miscellaneous industrial adhesive application-related activities. Although VOC reductions achieved by implementing th e recommended work practices may not be quantifiable, they are beneficial to the overall goal of reducing VOC emissions. We recommend work practices for storage, mixing operat ions, and handling operations for adhesives, thinners, and adhesive-related waste mat erials. We recommend these practices for use with all three of the control options described above.

Specifically, we recommend the following work pract ices: (1) store all VOC-containing adhesives, adhesive primers, and process-related wa ste materials in closed containers; (2) ensure that mixing and storage containers used for VOC-con taining adhesives, adhesive primers, and20

process-related waste materials are kept closed at all times except when depositing or removing these materials; (3) minimize spills of VOC-contain ing adhesives, adhesive primers, and process-related waste materials; and (4) convey VOC -containing adhesives, adhesive primers, and process-related waste materials from one locati on to another in closed containers or pipes.

E. Work Practices for Cleaning Materials

This CTG recommends work practices to reduce VOC em issions from cleaning materials used in miscellaneous industrial adhesive applicati on processes. These cleaning materials

include both materials used to clean surfaces befor e adhesive or adhesive primer application (surface preparation) and to clean application equi pment. Although VOC reductions achieved by implementing the recommended work practices may not be quantifiable, they are beneficial to the overall goal of reducing VOC emissions. We rec ommend work practices for storage, mixing operations, and handling operations for cleaning ma terials. We recommend these practices for use with all three of the control options described above

Specifically, we recommend that, at a minimum, the work practices include the following: (1) store all VOC-containing cleaning ma terials and used shop towels in closed containers; (2) ensure that storage containers used for VOC-containing cleaning materials are kept closed at all times except when depositing or removing these materials; (3) minimize spills of VOC-containing cleaning materials; (4) convey VOC-c ontaining cleaning materials from one location to another in closed containers or pipes; and (5) minimize VOC emission from cleaning of application, storage, mixing, and conveying equi pment by ensuring that equipment cleaning is performed without atomizing the cleaning solvent an d all spent solvent is captured in closed

containers.

VII. Cost Effectiveness of Recommended Control Opti ons

We used the 2002 National Emissions Inventory (NEI) database to estimate the number of facilities operating miscellaneous industrial ad hesive application processes. Based on the 2002 NEI, we estimated that there are a total of 1, 048 such facilities in the U.S. Using the 2004 ozone nonattainment designations, we estimated that a total of 720 of these facilities are in ozone

nonattainment areas. Based on the NEI VOC emission s data, 180 of the 720 facilities in ozone nonattainment areas emitted at or above the 6.8 kg/ day (15 lb/day) recommended VOC emissions applicability threshold from miscellaneou s industrial adhesive application processes. These 180 facilities emitted a total of about 4,428 Mg/yr of VOC (4,881 tpy), or an average of about 25 Mg/yr (27 tpy) of VOC per facility.

As previously mentioned, we are recommending in thi s CTG the VOC limits in the OTC

rule. We also mentioned earlier that the emission limits in the OTC rule were the California ARB RACT standards, which were based on eight Calif ornia Districts’ adhesives rules (including the Ventura County APCD regulation) and have been adopted by other California Districts and Maryland. The ARB based its cost eff ectiveness estimate on an analysis performed by Ventura County APCD in 1993 4 for a facility that manufactures commercial furnit ure. We therefore use the cost analyses by Ventura County A PCD and the California ARB scaled to 2007

dollars to estimate the cost effectiveness of our r ecommendations in this CTG. These cost

estimates are relevant to this CTG’s recommended le vels of control because they are based on21

the use of similar control measures (i.e., product substitution/reformulation and work practices) for miscellaneous industrial adhesive application proce sses.

In our analysis of the impacts of implementing the recommended levels of control in this CTG, we have assumed that all miscellaneous industr ial adhesive application facilities will

choose to utilize the low-VOC adhesive materials al ternative. We made this assumption for two reasons. First, since facilities are meeting equiv alent State and local limits, we believe that lowVOC adhesives that can meet the recommended control levels in this CTG are already available at a cost that is not significantly greater than th e cost of adhesives with higher VOC contents. Secondly, the use of add-on controls to reduce emis sions from typical adhesive application processes is a more costly alternative.

According to the 1993 Ventura County APCD Rule 74.2 0 Staff Report and the 1998 California ARB RACT determination, the annualized c ost for a facility to convert to waterborne adhesives was estimated to be $2,300 (1993$). Usin g the producer price index for adhesive manufacturing and scaling the 1993 annualized cost to 2007, we estimate the annualized cost to be $3,356. We believe that this estimate also repr esents the cost of implementing this CTG’s recommended VOC limits because the Ventura County A PCD regulation and the ARB RACT

determination is based on similar control measures. We assume that facilities in California and Maryland are already implementing the recommended m easures in this CTG. For the facilities we identified as emitting more than 6.8 kg/day (15 lb/day) in ozone nonattainment areas outside of California and Maryland, we estimate the total a nnual cost to be $603,997, based on the use of

low-VOC content adhesives. We estimate that the re commendations in this CTG will reduce

VOC emissions from miscellaneous industrial adhesiv es application processes by about 64 percent. This is a reduction of 2,070 Mg/yr (2,281 tpy of VOC) from these facilities. Therefore, we estimate the cost effectiveness to be $292 per M g ($265 per ton) of VOC emission reduction.

We believe that the work practice recommendations i n this CTG will result in a net cost savings. Implementing work practices reduces the a mount of cleaning materials used by reducing the amount that evaporates and is wasted. Similarly, we also believe that the recommendation to use the specified adhesive applic ation methods will also result in net cost savings. Increasing the transfer efficiency of adh esive application to reduce VOC emissions will also reduce adhesive consumption and costs. Howeve r, these cost savings cannot be accurately

estimated.

VIII. References

1. State of California Air Resources Board. Determination of Reasonably Available Control Technology and Best Available Retrofit Control Tech nology for Adhesives and Sealants

. December 1998.

2. Ozone Transport Commission. Model Rule for Adhesives and Sealants . Available at http://www.otcair.org/projects_details.asp?FID=99&f view=stationary#

3. State of California Air Resources Board. Determination of Reasonably Available Control Technology and Best Available Retrofit Control Tech nology for Adhesives and Sealants

. December 1998.22

4. Ventura County Air Pollution Control District. Staff Report Rule 74.20, Adhesives and

Sealants . June 8, 1993.

### Appendix A

DefinitionsThis page intentionally left blankA-1 

### Definitions

Acrylonitrile-butadiene-styrene or ABS welding means any process to weld acrylonitrile-butadiene-styrene pipe.

Adhesive means any chemical substance that is applied for t he purpose of bonding two surfaces together other than by mechanical means.

Adhesive primer means any product intended by the manufacturer for application to a substrate, prior to the application of an adhesive, to provide a bonding surface.

Aerosol adhesive or adhesive primer means an adhesive or adhesive primer packaged as an aerosol product in which the spray mechanism is permanently housed in a non-refillable can designed for handheld application without the n eed for ancillary hoses or spray equipment.

Ceramic tile installation adhesive means any adhesive intended by the manufacturer fo r use in the installation of ceramic tiles.

Chlorinated polyvinyl chloride plastic or CPVC plastic welding means a polymer of the vinyl chloride monomer that contains 67% chlori ne and is normally identified with a CPVC marking.

Chlorinated polyvinyl chloride welding or CPVC welding means an adhesive labeled for welding of chlorinated polyvinyl chloride plast ic.

Contact bond adhesive means an adhesive that: (i) is designed for applic ation to both surfaces to be bonded together, and (ii) is allowed to dry before the two surfaces are placed in contact with each other, and (iii) forms an immedia te bond that is impossible, or difficult, to reposition after both adhesive-coated surfaces are placed in contact with each other, and (iv) does not need sustained pressure or clamping of surfaces after the adhesive-coated surfaces have been brought together using sufficient momentary pressur e to establish full contact between both

surfaces. Contact adhesive does not include rubber cements that are primarily intended for use on paper substrates. Contact adhesive also does not include vulcanizing fluids that are designed and labeled for tire repair only.

Cove base means a flooring trim unit, generally made of viny l or rubber, having a concave radius on one edge and a convex radius on t he opposite edge that is used in forming a junction between the bottom wall course and the flo or or to form an inside corner.

Cove base installation adhesive means any adhesive intended by the manufacturer to be

used for the installation of cove base or wall base on a wall or vertical surface at floor level.

Cyanoacrylate adhesive means any adhesive with a cyanoacrylate content of at least 95 percent by weight.A-2

EPDM roof membrane means a prefabricated single sheet of elastomeric material composed of ethylene propylenediene monomer and tha t is field applied to a building roof using one layer or membrane material.

Flexible vinyl means non-rigid polyvinyl chloride plastic with at 5 percent by weight plasticizer content.

Indoor floor covering installation adhesive means any adhesive intended by the

manufacturer for use in the installation of wood fl ooring, carpet, resilient tile, vinyl tile, vinyl backed carpet, resilient sheet and roll or artifici al grass. Adhesives used to install ceramic tile and perimeter bonded sheet flooring with vinyl back ing onto a non-porous substrate, such as flexible vinyl, are excluded from this category.

Laminate means a product made by bonding together two or mor e layers of material.

Metal to urethane/rubber molding or casting adhesiv e means any adhesive intended by the manufacturer to bond metal to high density o r elastomeric urethane or molded rubber materials, in heater molding or casting processes, to fabricate products such as rollers for computer printers or other paper handling equipment

.

Motor vehicle adhesive means an adhesive, including glass bonding adhesiv e, used at a facility that is not an automobile or light-duty tr uck assembly coating facility, applied for the purpose of bonding two vehicle surfaces together wi thout regard to the substrates involved.

Motor vehicle glass bonding primer means a primer, used at a facility that is not an automobile or light-duty truck assembly coating fac ility, applied to windshield or other glass, or to body openings, to prepare the glass or body open ing for the application of glass bonding adhesives or the installation of adhesive bonded gl ass. Motor vehicle glass bonding primer includes glass bonding/cleaning primers that perfor m both functions (cleaning and priming of the windshield or other glass, or body openings) prior to the application of adhesive or the installation of adhesive bonded glass.

Motor vehicle weatherstrip adhesive means an adhesive, used at a facility that is not an automobile or light-duty truck assembly coating fac ility, applied to weatherstripping materials for the purpose of bonding the weatherstrip materia l to the surface of the vehicle.

Multipurpose construction adhesive means any adhesive intended by the manufacturer for use in the installation or repair of various co nstruction materials, including but not limited to drywall, subfloor, panel, fiberglass reinforced pla stic (FRP), ceiling tile and acoustical tile.

Outdoor floor covering installation adhesive means any adhesive intended by the

manufacturer for use in the installation of floor c overing that is not in an enclosure and that is exposed to ambient weather conditions during normal use.

Panel installation means the installation of plywood, pre-decorated h ardboard (or tileboard), fiberglass reinforced plastic, and simi lar pre-decorated or non-decorated panels to studs or solid surfaces using an adhesive formulate d for that purpose.A-3

Perimeter bonded sheet flooring installation means the installation of sheet flooring with vinyl backing onto a nonporous substrate using an adhesive designed to be applied only to a strip of up to four inches wide around the perimete r of the sheet flooring.

Plastic solvent welding adhesive means any adhesive intended by the manufacturer fo r use to dissolve the surface of plastic to form a bo nd between mating surfaces.

Plastic solvent welding adhesive primer means any primer intended by the manufacturer for use to prepare plastic substrates prior to bonding or welding.

Plastic foam means foam constructed of plastics.

Plastics means synthetic materials chemically formed by the polymerization of organic (carbon-based) substances. Plastics are usually co mpounded with modifiers, extenders, and/or reinforcers and are capable of being molded, extrud ed, cast into various shapes and films, or

drawn into filaments.

Polyvinyl chloride plastic or PVC plastic means a polymer of the chlorinated vinyl

monomer that contains 57% chlorine.

Polyvinyl chloride welding adhesive or PVC welding adhesive means any adhesive intended by the manufacturer for use in the welding of PVC plastic pipe.

Porous material means a substance that has tiny openings, often mi croscopic, in which fluids may be absorbed or discharged, including, bu t not limited to, paper and corrugated paperboard. For the purposes of this CTG, porous material does not include wood.

Reinforced plastic composite means a composite material consisting of plastic

reinforced with fibers.

Rubber means any natural or manmade rubber substrate, inc luding but not limited to, styrene-butadiene rubber, polychloroprene (neoprene ), butyl rubber, nitrile rubber, chlorosulfonated polyethylene and ethylene propylen e diene terpolymer.

Sheet rubber lining installation means the process of applying sheet rubber liners by hand to metal or plastic substrates to protect the underlying substrate from corrosion or abrasion. These operations also include laminating sheet rubb er to fabric by hand.

Single-ply roof membrane means a prefabricated single sheet of rubber, norma lly ethylene-propylenediene terpolymer, that is field a pplied to a building roof using one layer of membrane material. For the purposes of this CTG, single-ply roof membrane does not include membranes prefabricated from ethylene-propylenedien e monomer (EPDM).

Single-ply roof membrane installation and repair ad hesive means any adhesive labeled for use in the installation or repair of si ngle-ply roof membrane. Installation includes, as a minimum, attaching the edge of the membrane to th e edge of the roof and applying flashings to vents, pipes and ducts that protrude through the me mbrane. Repair includes gluing the edges ofA-4

torn membrane together, attaching a patch over a ho le and reapplying flashings to vents, pipes or ducts installed through the membrane.

Single-ply roof membrane adhesive primer means any primer labeled for use to clean and promote adhesion of the single-ply roof membran e seams or splices prior to bonding.

Structural glazing means a process that includes the application of ad hesive to bond glass, ceramic, metal, stone or composite panels to exterior building frames.

Subfloor installation means the installation of subflooring material ove r floor joists, including the construction of any load bearing jois ts. Subflooring is covered by a finish surface

material.

Thin metal laminating adhesive means any adhesive intended by the manufacturer fo r use in bonding multiple layers of metal to metal or metal to plastic in the production of electronic or magnetic components in which the thickness of th e bond line(s) is less than 0.25 millimeters.

Tire repair means a process that includes expanding a hole, te ar, fissure or blemish in a tire casing by grinding or gouging, applying adhesi ve and filling the hole or crevice with rubber.

Waterproof resorcinol glue means a two-part resorcinol-resin-based adhesive de signed for applications where the bond line must be resist ant to conditions of continuous immersion in

fresh or salt water.

### Appendix B

Summary of State and Local Requirements for VOC Emi ssions from

Adhesives and Adhesive PrimersThis page intentionally left blankB-1Appendix B. Summary of State and Local Requirements for VOC Emissions from Adhesives and Adhesive PrimersCalifornia DistrictAntelopeValleyBay AreaEl DoradoCountyPlacerCountySacramentoMetropolitanSan DiegoCountySan JoaquinValleyRule CitationRule 1168Rule 8-51Rule 236Rule 235Rule 460Rule 67.21Rule 4653General Adhesive Application ProcessesFiberglass200 200 200 200 200Flexible vinyl 250 250Flexible vinyl to other substrate 250Metal30 30 30 30 30 30 30Other Substrates 250 250 250 250 250Plastic Foams120 120 120 120 120Porous Material 120 120 120 120Porous Material (e.g. wood, plastic foam, but nota plastic)120Porous Material (except wood and plastic foam)Porous Material (except wood) 120 120Rubber250 250 250 250Wood30 30 30 30Specialty Adhesive Application ProcessesABS Welding400 400 350 400 400 400 400Adhesive Primer for Plastic 250 250Carpet Pad Installation 150 150Cellulosic plastic welding (except ethyl cellulose)Ceramic Tile Installation 130 130 130 130 130 130 130Computer Diskette Manufacturing 350 850 350 850 850850Contact Adhesive - General 250Contact Adhesive - Special 400 250Contact Adhesive - Specialty Substrate 250Contact Adhesive 200 250 250Cove Base Installation 150 150 150 150 150 150CPVC Welding270 490 250 490 490 490 490Dry Wall and Panel Installation 200 200Elastomeric Adhesive 750Floor covering installation (except ceramic tile)B-2Appendix B. Summary of State and Local Requirements for VOC Emissions from Adhesives and Adhesive PrimersCalifornia DistrictAntelopeValleyBay AreaEl DoradoCountyPlacerCountySacramentoMetropolitanSan DiegoCountySan JoaquinValleyRule CitationRule 1168Rule 8-51Rule 236Rule 235Rule 460Rule 67.21Rule 4653Floor covering installation 150Immersible Product Manufacturing 650Indoor Carpet AdhesivesIndoor Floor Covering Installation 150 150 150150Metal to Urethane/Rubber Molding or CastingAdhesive250 250 850Multipurpose Architectural (except cove baseinstallation)Multipurpose Construction 200 200 200 200 200Nonmembrane Roof Installation/Repair 300 300 300 300Non-Vinyl Backed Indoor Carpet Installation 150 150Other Plastic Cement Welding Adhesive 450 450510 450Other Plastic Welding 500Outdoor Floor Covering Installation 350 250 250250Perimeter Bonded Sheet Vinyl FlooringInstallation660 660 660 660Plastic Cement Welding 250 250PVC Welding285 510 250 510 510 510 510Rubber Floor Installation 150 150Rubber Vulcanization Bonding 850 850Sheet rubber lining installation adhesive850Single-Ply Roof Material Installation/Repair 250250Single-Ply Roof Membrane Installation/RepairAdhesive250 250 250Solvent welding adhesiveStaple and Nail Manufacturing 640Structural Glazing 100 100 100 100 100Structural Wood Member AdhesiveStyrene-acrylonitrile welding adhesiveSubfloor Installation200 200Thin Metal Laminating 780 250 780 780B-3Appendix B. Summary of State and Local Requirements for VOC Emissions from Adhesives and Adhesive PrimersCalifornia DistrictAntelopeValleyBay AreaEl DoradoCountyPlacerCountySacramentoMetropolitanSan DiegoCountySan JoaquinValleyRule CitationRule 1168Rule 8-51Rule 236Rule 235Rule 460Rule 67.21Rule 4653Tire Retread 100 100 100 100Top and Trim Installation 540Traffic Marking Tape AdhesiveVCT and Asphalt Tile Installation 150 150Waterproof Resorcinol Glue 170 170 170 170 170Wood Flooring Installation 150 150Adhesive Primer Application ProcessesAutomotive Glass700 700 700 700Plastic Cement Welding650 650 400 650 650Single-Ply Roof Membrane 250 250Traffic Marking Tape150 150 150 150OtherIncludedAbove250IncludedAbove250 250 250 250Natural gas pipeline tape adhesive primer600B-4Appendix B. Summary of State and Local Requirements for VOC Emissions from Adhesives and Adhesive PrimersCalifornia District / StateSantaBarbaraCountyShastaCountySouth CoastTehamaCountyVenturaCountyYolo-SolanoMaryland(OTCModel Rule)Rule CitationRule 353Rule 3:32Rule 1168Rule 4:40Rule 74.20Rule 2.33COMAR26.11.35General Adhesive Application ProcessesFiberglass200 200 80 200 200 200Flexible vinyl250 250 250 250 250Flexible vinyl to other substrate 250 250 250Metal30 30 30 30 30 30 30Other Substrates250 250 250 250 250 250Plastic Foams120 50 120 120 120Porous Material 120 150 120Porous Material (e.g. wood, plastic foam, but nota plastic)120 120Porous Material (except wood and plastic foam)150Porous Material (except wood) 50Rubber250 250 250 250Wood30 30Specialty Adhesive Application ProcessesABS Welding400 400 325 400 400 400Adhesive Primer for PlasticCarpet Pad Installation 50Cellulosic plastic welding (except ethyl cellulose)100Ceramic Tile Installation 130 130 65 130 130 130 130Computer Diskette Manufacturing 850 850 350 850850Contact Adhesive - GeneralContact Adhesive - Special 250Contact Adhesive - Specialty Substrate 400 250 250 200Contact Adhesive250 250 80 250 200 250Cove Base Installation 150 150 50 150 150 150CPVC Welding490 490 490 490 490 490Dry Wall and Panel Installation 50Elastomeric AdhesiveB-5Appendix B. Summary of State and Local Requirements for VOC Emissions from Adhesives and Adhesive PrimersCalifornia District / StateSantaBarbaraCountyShastaCountySouth CoastTehamaCountyVenturaCountyYolo-SolanoMaryland(OTCModel Rule)Rule CitationRule 353Rule 3:32Rule 1168Rule 4:40Rule 74.20Rule 2.33COMAR26.11.35Floor covering installation (except ceramic tile)150Floor covering installationImmersible Product ManufacturingIndoor Carpet Adhesives 50Indoor Floor Covering Installation 150 150 150150 150Metal to Urethane/Rubber Molding or CastingAdhesive850 250 250 850Multipurpose Architectural (except cove baseinstallation) 200Multipurpose Construction 200 200 70 200 200 200Nonmembrane Roof Installation/Repair 300 300 300300 300Non-Vinyl Backed Indoor Carpet InstallationOther Plastic Cement Welding Adhesive 510 450 450510Other Plastic Welding 500Outdoor Floor Covering Installation 250 250 150 250250Perimeter Bonded Sheet Vinyl FlooringInstallation660 660 660 660Plastic Cement Welding 250 450PVC Welding510 510 510 510 510 510Rubber Floor Installation 60Rubber Vulcanization BondingSheet rubber lining installation adhesive 850 850850Single-Ply Roof Material Installation/Repair250Single-Ply Roof Membrane Installation/RepairAdhesive250 250 250 250 250 250Solvent welding adhesive 450Staple and Nail Manufacturing 640Structural Glazing100 100 100 100 100 100 100Structural Wood Member Adhesive 140Styrene-acrylonitrile welding adhesive 100Subfloor Installation 50B-6Appendix B. Summary of State and Local Requirements for VOC Emissions from Adhesives and Adhesive PrimersCalifornia District / StateSantaBarbaraCountyShastaCountySouth CoastTehamaCountyVenturaCountyYolo-SolanoMaryland(OTCModel Rule)Rule CitationRule 353Rule 3:32Rule 1168Rule 4:40Rule 74.20Rule 2.33COMAR26.11.35Thin Metal Laminating 780 780 780 780Tire Retread100 100 100 100 100 100Top and Trim Installation 540 250 540Traffic Marking Tape Adhesive 150VCT and Asphalt Tile Installation 50Waterproof Resorcinol Glue 170 170 170 170Wood Flooring Installation 100Adhesive Primer Application ProcessesAutomotive Glass700 700 700 700 700Plastic Cement Welding 650 650 400 650 650Single-Ply Roof Membrane 250 250 250 250 250Traffic Marking Tape 150 150 150 150Other250 250IncludedAbove250 250IncludedAbove250Natural gas pipeline tape adhesive primer

### Appendix C

Summary of State and Local Requirements for Applica tion Method and Control EfficiencyThis page intentionally left blankC-1Appendix C. Summary of State and Local Requirements for Application Method and EfficiencyCalifornia DistrictAntelopeValleyBay AreaEl DoradoCountyPlacerCountySacramentoMetropolitanSan DiegoCountySan JoaquinValleyRule CitationRule 1168Rule 8-51Rule 236Rule 235Rule 460Rule 67.21Rule 4653Adhesive Application MethodAerosol Cansx xAir-Assisted Airless Spray xAir-Atomized (for contact adhesives) xAirless Spray, Air-Assisted Airless Spray, AirAtomized Spray (for contact adhesives)x xAirless Spray, Air-Assisted Airless Spray, AirAtomized Spray (for viscosity 200 cp or grater)xBrush or Roll Coat x x x x xDip Coatx x x x xElectrodepositionx x xElectrostatic Spray x x x x xFlow Coatx x x x xHand Application x x x x xHVLP Sprayx x x x xLVLP Sprayx x xOther, Transfer Efficiency Minimum 65%x, nonespecified65%Add-On Control EfficiencyCapture Efficiency 90% by wt 90% by wtControl Efficiency 95% by wt 95% by wtOverall Efficiency 85% 85% 85% by wt 85% by wtOverall VOC Reduction Efficiency 80% by wtC-2Appendix C. Summary of State and Local Requirements for Application Method and EfficiencyCalifornia District / StateSantaBarbaraCountyShastaCountySouth CoastTehamaCountyVenturaCountyYolo-SolanoMaryland(OTCModel Rule)Rule CitationRule 353Rule 3:32Rule 1168Rule 4:40Rule 74.20Rule 2.33COMAR26.11.35Adhesive Application MethodAerosol Cansx x xAir-Assisted Airless SprayAir-Atomized (for contact adhesives)Airless Spray, Air-Assisted Airless Spray, AirAtomized Spray (for contact adhesives)x x xAirless Spray, Air-Assisted Airless Spray, AirAtomized Spray (for viscosity 200 cp or grater)xBrush or Roll Coat x x x xDip Coatx x x xElectrodepositionx x xElectrostatic Spray x x x xFlow Coatx x x xHand Applicationx x x xHVLP Sprayx x x xLVLP Sprayx x xOther, Transfer Efficiency Minimumx, nonespecified65%x, nonespecifiedx, nonespecifiedAdd-On Control EfficiencyCapture Efficiency 90% by wt 90% by wtControl Efficiency 95% by wt 95% by wtOverall Efficiency 85% by wt 85% by wt 85% by wtOverall VOC Reduction Efficiency 80% 85% by wtUnited StatesEnvironmental ProtectionAgencyOffice of Air Quality Planning and StandardsSector Policies and Programs DivisionResearch Triangle Park, NCPublication No. EPA 453/R-08-005September 2008