Control Techniques Guidelines for
Large Appliance Coatings
-------
This page intentionally left blank.
11
-------
EPA 453/R-07-004
September 2007
Control Techniques Guidelines for
Large Appliance Coatings
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Sector Policies and Programs Division
Research Triangle Park, NC
-------
This page intentionally left blank.
IV
-------
TABLE OF CONTENTS
I. Introduction Page 1
II. Background and Overview Page 2
III. Applicability Page 3
IV. Process Description and Sources of VOC Emissions Page 4
A. Process Description
B. Source of VOC Emissions
1. Coatings
2. Cleaning Materials
V. Available Controls and Existing Federal, State, and Local
Recommendations/Regulations Page 8
A. Available Controls for VOC Emissions from Coatings
1. Pollution Prevention Measures
a. Product Substitution/Reformulation
b. Work Practices
2. Emission Capture and Add-On Control Systems
B. Available Controls for VOC Emissions from Cleaning Materials
1. Pollution Prevention Measures
2. Emission Capture and Add-On Control Systems
C. Existing Federal, State, and Local Recommendations/Regulations
1. Thel977CTG
2. Thel982NSPS
3. The 2002 NESHAP
4. Existing State and Local VOC Requirements
VI. Recommended Control Options Page 18
A. Emissions Limit based on Low-VOC Coatings
B. Optional Add-On Controls for Coating Operations
C. Work Practices for Coating Operations and Cleaning Materials
VII. Cost Effectiveness of Recommended Control Options Page 21
VIII. References Page 22
Appendix A
1977 Large Appliance Coating CTG Document
Appendix B
Summary of State-Specific Large Appliance Coating Regulations
-------
This page intentionally left blank.
VI
-------
I. Introduction
Clean Air Act (CAA) section 172(c)(l) provides that state implementation plans
(SIPs) for nonattainment areas must include "reasonably available control measures"
(RACM), including "reasonably available control technology" (RACT), for sources of
emissions. Section 182(b)(2)(A) provides that for certain nonattainment 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 capable 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 Federal Register notices,
EPA has addressed how States can meet the RACT requirements of the Act.
CAA section 183(e) directs EPA to list for regulation those categories of products
that account for at least 80 percent of the 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); see also 71 FR 28320 (May 16, 2006), 70
FR 69759 (Nov. 17, 2005); 64 FR 13422 (March 18, 1999). Large appliance coatings 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 VOC from large appliance
coatings. In developing this CTG, EPA evaluated the sources of VOC emissions from the
large appliance coating industry and the available control approaches for addressing these
emissions, including the costs of such approaches. Based on available information and data,
EPA provides recommendations for RACT for large appliance coating.
States can use the recommendations in this CTG to inform their own determination
as to what constitutes RACT for VOC for large appliance coatings in their particular
nonattainment areas. The information contained in this document is provided only as
guidance. This guidance does not change, or 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 control agencies to consider in
determining RACT. State and local pollution control agencies are 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 may not apply to a particular
situation based upon the circumstances of a specific source. Regardless of whether a State
chooses to implement the recommendations contained herein through State rules, or to issue
State rules that adopt different approaches for RACT for VOC from large appliance
-------
coatings, States must submit their RACT rules to EPA for review and approval 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 rules to meet the RACT
requirements of the CAA and EPA's regulations. To the extent a State adopts any of the
recommendations in this guidance into its State RACT rules, interested parties can raise
questions and objections about the substance of this guidance and the appropriateness of the
application of this guidance to a particular situation during the development of the State
rules and EPA's SIP approval process.
CAA section 182(b)(2) requires that a CTG issued after November 15, 1990 and the
date of attainment include the date by which 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 section 182(b)(2), States required to
submit rules consistent with section 182(b) must submit their SIP revisions within one year
of the date of issuance of the final CTG for large appliance coatings. States subject only to
the RACT requirement in CAA section 172(c)(l) may take action in response to this CTG,
as necessary to attain.
II. Background and Overview
In December 1977, EPA published a CTG for large appliance coating, entitled
"Control of Volatile Organic Emissions from Existing Stationary Sources, Volume V:
Surface Coating of Large Appliances," EPA-450/2-77-034 (1977 CTG). The 1977 CTG can
be downloaded from EPA's website at www.epa.gov/ttn/naaqs/ozone/ctg_act. The cover
page of the 1977 CTG is included as Appendix A to this CTG for additional reference. In
October 1982, EPA promulgated the National Standards of Performance for New Stationary
Sources (NSPS): Standards of Performance for Industrial Surface Coating: Large
Appliances, 40 CFR part 60, subpart SS (1982 NSPS). In 2002, EPA promulgated the
National Emission Standards for Hazardous Air Pollutants: Surface Coating of Large
Appliances, 40 CFR part 63, subpart NNNN (2002 NESHAP). The 1977 CTG recommends
and the 1982 NSPS requires VOC emissions limits based on VOC content of low VOC
coating materials. The 2002 NESHAP establishes organic hazardous air pollutants (HAP)
emissions limits based on the organic HAP content of low organic HAP coating materials.
At least 24 State and local jurisdictions have specific regulations that control VOC
emissions from large appliance coating operations. A discussion of the applicability and
control options found in the Federal actions and State and local rules is presented in Section
V of this document.
EPA developed the recommended approaches contained in this document after
reviewing the 1977 CTG, the 1982 NSPS, the 2002 NESHAP, and existing State and local
VOC emission reduction approaches and considering information obtained since issuance of
the 2002 NESHAP.
The remainder of this document is divided into six sections. Section III describes the
scope of sources to which the control recommendations in this CTG could apply. Section
IV describes the large appliance coating processes and identifies the sources of VOC
emissions from those processes. Section V describes the available control approaches for
addressing VOC emissions from this product category and summarizes Federal, State and
-------
local approaches for addressing such emissions. Section VI provides our recommendations
for RACT for large appliance coatings. Section VII discusses the cost-effectiveness of the
recommended control approaches. Section VIII contains a list of references.
III. Applicability
This CTG provides control recommendations for reducing VOC emissions stemming
from the use of coatings in large appliance coating operations. Coatings include paints,
sealants, caulks, inks, adhesives, and maskants.1 This section addresses EPA's
recommendations as to the scope of entities to which the RACT recommendations in this
CTG should apply. As explained above, this document is a guidance document and
provides information for States to consider in determining RACT. When State and local
pollution control agencies develop RACT rules, they may elect to adopt control approaches
that differ from those described in this document and/or promulgate applicability criteria
that differ from those recommended here.
In terms of applicability, we recommend that the control approaches discussed in
Section VI of this CTG apply to each large appliance coating unit2 at a facility where the
total actual VOC emissions from all large appliance coating operations, including related
cleaning activities, at that facility are equal to or exceed 6.8 kg/day (15 Ib/day), or an
equivalent level such as 3 tons per 12-month rolling period, before consideration of controls.
We do not recommend these control approaches for facilities that emit below this level
because of the very small VOC emission reductions that can be achieved. The
recommended threshold level is equivalent to the evaporation of about 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 using exclusively powder or ultra-violet and electron
beam (UV/EB) coatings. Furthermore, based on the 2002 National Emission Inventory
(NEI) and the 2004 ozone nonattainment designations, we estimated that all of the large
appliance surface coating facilities located in ozone nonattainment areas (68 facilities) emit
at or above this level and would therefore be addressed by our recommendations in the
CTG. For purposes of determining whether a facility meets our recommended applicability
threshold, aggregate emissions, before consideration of control, from all large appliance
coating operations (including related cleaning activities) at a given facility are included.
In developing their RACT rules, State and local agencies should consider carefully
the facts and circumstances of the affected sources in their States. As noted above, States
can adopt the above recommended 15 Ib/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 RACT rules in the context of the SIP
revision process.
1 Decorative, protective, or functional materials that consist only of protective oils for metal, acids, bases, or
any combination of these substances are not considered metal furniture coatings.
2 A coating unit consists of a series of one or more coating applicators and any associated drying area and/or
oven wherein a coating is applied, dried, and/or cured. A coating unit ends at the point where the coating is
dried or cured, or prior to any subsequent application of a different coating. It is not necessary for a coating
unit to have an oven or a flash-off area.
-------
The 2002 NEI and a questionnaire sent to industry by EPA during the 2002
NESHAP development (data requested by EPA in 1997 and 1998) were used as the source
of emissions data and statistical information concerning the large appliance coating industry
as a whole. There were several discrepancies in the number of facilities reporting in the
2002 NEI versus the 1997 and 1998 NESHAP questionnaires. During the evaluation of the
2002 NEI data, it was noted that 14 States had at least one facility that reported emissions
from this source category in 1997 but not in 2002. There were also States that showed a
number of facility closures based on the comparison of 2002 NEI data to the data collected
during the 2002 NESHAP development.
Results from the NESHAP questionnaires indicated that there were 222 facilities that
perform large appliance coating operations. These operations were distributed across 38
States and Puerto Rico. The States with the largest number of large appliance coating
operations were Ohio (19), Tennessee (16), Illinois (15), Texas (14), Wisconsin (13), and
Georgia (10). Although information regarding HAP emissions was the main focus of the
NESHAP questionnaires, information regarding VOC was submitted from 153 of the total
222 facilities surveyed. These facilities reported actual VOC emissions totaling
approximately 5,000 tpy for 1997. This total only accounts for the VOC emissions
generated by these facilities from coatings. In addition, facilities that were excluded from
the final rule (coating of chillers) were also included in the total 222 facilities surveyed.
In developing this CTG, the 2002 NEI database was queried for VOC emissions
generated by facilities that were listed under the SIC codes 3631, 3632, 3633, 3639, 3582,
3585, and 3589 (those SIC used for the 2002 NESHAP). This query resulted in only 128
facilities compared to the 222 facilities identified during the 1997 and 1998 NESHAP
questionnaires. The 128 large appliance coating facilities in the 2002 NEI reported total
VOC emissions of 6,225 tpy. This total accounts for all of the VOC emissions generated by
these facilities and does not specify the amount generated just by large appliance coating
operations. Of the 128 facilities that reported, 44 were located in nonattainment areas.
Based on the industry information submitted during the 2002 NESHAP
development, it was anticipated that closer to 200 facilities (excluding the number of
facilities that reported when chillers were part of the rule development) should have reported
during 2002. Based on the fact that only 128 facilities reported and the discrepancies noted,
it can be concluded that the 2002 NEI is not as complete as the data collected during the
2002 NESHAP development. Based on the information evaluated for this CTG
development, there are an estimated 200 facilities. Approximately 68 of these facilities are
believed to be in nonattainment areas. This is based on the fact that 44 facilities out of the
128 large appliance coating facilities (34 percent) that reported emissions in the 2002 NEI
were in nonattainment areas (34 percent of the 200 facilities from the 2002 NESHAP
development would be 68 facilities estimated to be in nonattainment areas). Baseline VOC
emissions from these 68 facilities are estimated to be 3,300 tpy.
IV. Process Description and Sources of VOC Emissions
A. Process Description
Large appliance coatings include, but are not limited to, materials referred to as
paint, topcoats, basecoats, primers, enamels, and adhesives used in the manufacture of large
-------
appliance parts or products. A large appliance part is defined as any organic surface-coated
metal lid, door, casing, panel, or other interior or exterior metal part or accessory that is
assembled to form a large appliance product. A large appliance product is also defined as
any organic surface-coated metal range, oven, microwave oven, refrigerator, freezer,
washer, dryer, dishwasher, water heater, or trash compactor manufactured for household,
commercial, or recreational use.
Coatings are a critical constituent to the large appliance industry. Coatings protect
the metal from corrosion by providing resistance to moisture, heat, detergent, and sometimes
the outdoor elements. Coatings for each type of large appliance have special requirements
and contain unique properties because each type will be exposed to somewhat different
corrosive elements. The coatings must also be durable and have excellent adhesion
properties to avoid peeling or chipping. Finally, the coatings that are applied on home
appliances must have esthetic appeal.
The coating application methods used are typical of surface coating operations in
many industries. Air atomized spraying and airless spraying of coatings involve the
atomization of a liquid coating in order to apply it to a substrate. Air atomized spraying
achieves atomization by the use of compressed air and can provide transfer efficiencies of
up to 40 percent. Airless spraying uses an airless pump system to force the coating through
a nozzle designed to atomize the coating and typically has a transfer efficiency of 50 to 60
percent. The high-volume low-pressure (HVLP) system is a newer technology which
further reduces overspray because it propels the atomized coating at a lower velocity than
the air or airless system.
Most spray applied large appliance coatings are applied electrostatically. An
electrostatic spray can be generated using an air or an airless gun system. In such systems,
the transfer efficiency is improved because electrostatic principles are used to attract the
coating to the substrate (up to about 85 percent transfer efficiency). Other electrostatic
application methods include electrostatic bell and disk spray gun systems. The electrostatic
bell and disk systems are similar in many respects. They use the rapid rotation of either a
bell or disk shaped applicator to mist the coating. The use of oppositely charged substrate
and coating allows for higher transfer efficiencies (close to 90 percent) and better coating
uniformity.
Other application methods commonly used are dip coating, electrodeposition, and
flow coating. The dip coating operation involves the immersion of a part into a tank
containing the coating and typical transfer efficiencies are near 85 percent.
Electrodeposition is a dip coating method in which an electric field is used to facilitate the
deposition of the waterborne coating on the substrate. The substrate to be coated acts as an
electrode that is oppositely charged from the coating (particles) in the dip tank.
Electrodeposition has a transfer efficiency closer to 95 percent. Flow coating is a method
that involves the application of the coating directly onto the substrate without atomizing the
coating and has a typical transfer efficiency of 85 percent.
In typical liquid spray and dip coating operations the coated parts/products typically
move from the coating application area through a flash-off area, where solvents in the
coating begin to evaporate slowly, thus avoiding bubbling of the coating while it is curing in
the oven. After being coated by any of the typical coating operations, large appliance
-------
products are dried and cured using heated dryers or by air drying. This step removes any
remaining volatiles from the coatings so that the surfaces of the large appliance products
meet the hardness, durability, and appearance requirements of customers.
The majority of touch-up operations are performed by using manual air spray guns
and a lacquer based coating. This is because the lacquer coating has good drying
characteristics that allow for shorter drying times. In some cases, touch-up might include
recoating a product entirely, but the majority of touch-up consists of manual coating
application to a small portion of the product surface.
B. Sources of VOC Emissions
VOC emissions from large appliance coating processes result from the evaporation
of the components of the coatings and cleaning materials.3 Provided below are further
descriptions of these two emission sources.
1. Coatings
The primary VOC emissions from large appliance coatings occur during coating
application (prime, single or topcoat application)/flash-off and drying/curing of the coatings.
The remaining emissions are primarily from mixing and/or thinning. In most cases, VOC
emissions from storage, handling, and waste/wastewater operations related to coating
operations are relatively small.
After being coated by any of the typical coating operations (such as spray coating or
dip coating), the large appliance products are cured using heated dryers or allowed to air dry.
This step removes any remaining volatiles from the coating so that the surfaces of the large
appliance product meet the hardness, durability, and appearance requirements of the
customers.
Coating mixing may be performed in an agitated drum or it may be performed by
merging two different coating supply lines into one. Coating mixing is typically performed
by the coating manufacturer prior to shipment to a large appliance manufacturer's facility.
Some facilities add water or solvent to the coating (thinning), which may be performed in a
small mixing booth or it may be automated. Some facilities combine reclaimed coating
from various coating operations and mix the different coatings together in a drum. Mixing
also varies depending on the type of coating and usage requirements.
Until the 1970's, conventional solvent-based coatings, with high VOC content, were
the majority of coatings used in the large appliance industry. Due to increased regulation at
the State and federal level, the industry has steadily moved to lower VOC content coatings.
These alternative coatings include powder coatings, waterborne coatings, higher solids
coatings and ultraviolet coatings. The following discussion summarizes each of these
alternative coating formulations.
3 In a previous Federal Register notice, EPA identified specific categories, including large appliances coating,
the cleaning operations of which would not be covered by EPA's 2006 CTG for industrial cleaning solvents.
71 Fed Reg. 44522, 44540 (2006). In that notice, EPA expressed its intention to address cleaning operations
associated with these categories in the CTGs for these specified categories if the Agency determines that a
CTG is appropriate for the respective categories.
-------
Powder Coatings. The use of powder coating systems in the large appliance industry
has increased. Many large appliance coating facilities have replaced existing liquid coating
operations with powder coating operations. Compared to conventional liquid coating
systems, powder coating produces minimal amounts of VOC emissions because powder
coatings are applied as dried particles, no VOC are released during the application operation,
and volatile emissions from the curing operation, if any, are generally much less than the
volatile emissions from liquid coating systems. Powder coating is applied via powder
delivery systems, which in most cases is an electrostatic spray. Particulate emissions
resulting from the application of powder coatings can be minimized through the
implementation of a recovery and recycling process (reuse of overspray). Depending on the
powder formulation, some volatile emissions may occur when the powder is heated during
the curing step. Powder coating applications are best suited for long production runs of
consistently sized parts without color changes. In the case of some products with special
performance needs (such as dishwasher racks), a two-step powder coating process may be
used. In these cases, the powder coating is preceded by a low-solids adhesion enhancer.
Waterborne Coatings. Waterborne coatings produce minimal VOC emissions
primarily because a large portion of the solvent carrier is replaced with water. The water
component can constitute as much as 80 percent of the coating, with the remaining 20
percent being the coating solids.
Higher Solids Coatings. These coatings contain at least 60 percent by volume of
coating solids. VOC emissions are reduced through the use of these coatings because they
contain less solvent per unit volume of solids than conventional solvent-based coatings.
Thus, a lesser amount of VOC emissions are released during coating preparation,
application, and curing to deliver a given amount of coating solids.
Ultraviolet Coatings. Ultraviolet (UV) curable liquid and UV curable powder
coatings are used for heat sensitive substrates as they allow for low curing temperatures.
UV liquid coatings have been used for several decades on parts made of wood, composite,
and metal, but are not commonly used in the large appliance industry. Because the entire
coating must be exposed to the UV light source to achieve complete curing of the UV
coating, UV curable coating applications present problems in the large appliance industry.
Pigmentation used in the majority of large appliance coatings blocks the UV light. The
shape of the large appliance also presents curing problems. Many large appliance products
have bends or are box-shaped, creating areas which would be shaded from the UV light
source.
2. Cleaning Materials
Another main source of VOC emissions from large appliance coating is the cleaning
materials. Proper cleaning removes all organic and inorganic soils from the substrate prior
to coating, which is critical for achieving maximum performance from the coating,
especially with powder coating. Cleaning and pretreatment can consist of numerous stages
that include several types of chemical washes, such as solvent cleaning, an acid wash, a
phosphate wash, and a deionized water wash. Facilities use various combinations of these
stages. Except for solvent cleaning and wetting oil treatment, most stages do not emit any
VOC emissions. Pretreatment and cleaning requirements vary depending on the type of
coating application and curing, as well as the type of metal to be coated.
-------
Cleaning materials are also used to clean coating equipment and to touch up the final
products. These materials are typically VOC solvents such as methyl ethyl ketone (MEK)
and toluene. However, there has been an increase in the use of alcohol and water-based
cleaners.
V. Available Controls and Existing Federal, State, and Local
Recommendations/Regulations
As previously mentioned, there are two main sources of VOC emissions from large
appliance coating operations: (1) evaporation of VOC from the coatings; and (2)
evaporation of VOC from the cleaning materials. This section summarizes the available
control options for reducing these VOC emissions and existing State and local VOC
requirements.
A. Available Controls for VOC Emissions from Coatings
There are two general types of emission control techniques for reducing VOC
emissions from large appliance coatings: pollution prevention measures and emission
capture and add-on control systems. Pollution prevention is the most prevalent control
technique being used by the large appliance surface coating industry. Add-on control
systems are available to the industry, but few facilities utilize this control technique.
Provided below is a summary of each of these types of control techniques.
1. Pollution Prevention Measures
Pollution prevention measures applicable to the large appliance industry, including
product substitution/reformulation and work practice procedures, may be used to decrease
VOC emissions from large appliance coatings. Coatings with low VOC content, such as
waterborne coatings, higher solids solvent-borne coatings and powder coatings, may be used
to reduce VOC emissions from coatings by reducing or eliminating the organic solvent
present in the coatings. Work practice procedures may also reduce VOC emissions from
coatings during paint mixing, paint storage, and paint transfer operations.
a. Product Substitution/Reformulation
The use of waterborne, higher solids, and powder coatings has increased since 1977.
Paint manufacturers have developed and are continuing to develop waterborne, higher
solids, and powder coating formulations that replace conventional solvent-borne coatings.
These coatings are generally available and often are not produced and marketed specifically
for the large appliance coating industry. Conversion to these coatings can lower VOC
emissions greatly, and most coatings operations, including most large appliance coating, are
capable of converting to these coatings.
b. Work Practices
Work practice procedures are physical actions intended to affect emission reductions.
Because work practice procedures are specifically tailored to an industry, they may vary
from a few manual operations to a complex program.
For the large appliance industry, work practice procedures may be appropriate for the
following activities:
Coating Storage and Handling:
-------
Storage demands vary based on the type of coating and usage requirements.
Container size and type vary depending on coating manufacturer and end user needs.
Most coatings are stored in 208 liter (55 gallon) drums. Powder coatings can also be
stored in drums, as long as the temperature and the humidity are controlled. Most
facilities store powder coatings in 23 kilogram (50 pound) cardboard boxes that are
lined with plastic to prevent moisture absorption, but the size of the container can
vary from 1.4 to 136 kilograms (3 to 300 pounds). These containers should be well
maintained to prevent leakage and excessive spillage or material loss during transfer
to other containers or coating equipment. They should also remain sealed except
when it is necessary to remove material from the containers, after which they should
be promptly closed again.
Fluid Handling Equipment:
All fluid handling equipment such as coating supply lines, holding tanks, coating
storage containers, or any fluid handling equipment that contains a VOC-containing
coating should be well maintained to prevent spills, leaks, or other problems that
would release some of the contents of the fluid handling system.
Mixing Operations:
Coating mixing may be performed in an agitated 208 liter drum, or it may be
performed by merging two different coating supply lines into one. Mixing vessels
should have a top that prevents VOC emissions during the agitation process. Store
mixed coatings and solvents in closed containers when not being combined to reduce
VOC emissions.
Some large appliance coating facilities, either pursuant to Federal, State and/or local
regulations or on their own initiatives, develop and implement work practice plans to control
VOC emissions. These plans set forth the steps to be taken to ensure that work practices are
implemented properly to minimize VOC emissions during coating processes. Such a plan is
a compliance option under the 2002 NESHAP. The use of a work practice plan is a
traditional approach for reducing emissions during cleaning operations in various industries,
including the large appliance coating industry. As shown by these industries, work practice
plans can be easily adopted and managed.
2. Emission Capture and Add-On Control Systems
In addition to pollution prevention measures, VOC emissions from large appliance
surface coating operations can be reduced by the use of capture systems, in conjunction with
add-on control systems that either destroy or recover the VOC in the exhaust streams. As
stated previously, although capture systems and add-on control devices are available to the
large appliance surface coating industry, EPA is aware of only a few cases where this
control technology is utilized by the industry. The majority of VOC emissions from large
appliance coating operations occur in the spray booth. Spray booths typically exhaust a high
volume of air with a low concentration of VOC which can result in a high cost of control.
The prevalent method of destruction of organic solvent emissions from coatings is
thermal oxidation. The organic solvent-containing exhaust air is heated to a very high
temperature, which converts it to carbon dioxide and water through the process of
combustion. There are several options for VOC control by oxidation. They include:
(1) direct, gas-fired, thermal recuperative oxidation; (2) direct, gas-fired, thermal
-------
regenerative oxidation; (3) direct, electrically heated, thermal regenerative oxidation; (4)
direct, electrically heated, catalytic oxidation; and (5) direct, gas-fired, catalytic oxidation.
Direct, gas-fired, thermal recuperative oxidizers usually operate at temperatures of
760 C (1400 F) and use a natural gas burner. The residence time for organic solvent rich
air is about 0.5 seconds. This type of unit is usually constructed solely of steel and utilizes
heat exchangers to recover heat. These oxidizers can achieve a high VOC destruction (98
percent efficient or better), especially when the VOC concentration in the inlet stream is
high. These devices are not the most efficient for heat recovery, but it is possible to use
waste heat to produce steam or heated air. Their all steel construction becomes a problem
when hydrochloric acid is produced as a product of the combustion of chlorinated organic
solvents.
Direct, gas-fired, thermal regenerative oxidizers utilize ceramic towers in a 3-, 5- or
7-chamber configuration to achieve heat recovery efficiencies in the 80-95 percent range.
For this reason, the unit produces less NOx emissions and uses very little natural gas.
Regenerative oxidizers can be effective for airstreams with flow rates of 280 to 4,250 cubic
meters per minute (10,000 to 150,000 cubic feet per minute). Regenerative oxidizers are
capable of achieving high destruction efficiencies similar to those of recuperative oxidizers.
Direct, electrically heated, thermal regenerative oxidizers are based on the principle
that if enough organic solvent emissions enter the unit at high concentrations then the
combustion process will maintain itself using only the heat of the organic solvent
combustion. Electric coils within the unit are used to bring the unit up to its operating
temperature (760 C) as well as to help maintain operating temperature when the organic
solvent concentrations in the effluent stream drop below critical levels. The unit itself
creates no NOx, CO, or CO2 emissions because it operates on electricity instead of the
combustion of natural gas or other fuels. Some problems with these types of units include a
long startup time and costly operation due to the electricity required to operate them
properly. Another problem with this type of oxidizer is that hydrochloric acid from the
oxidation of chlorinated organic solvents can destroy the electric coils in the unit.
Direct, electrically heated, catalytic oxidizers use precious metal catalysts as an
integral part of the combustion chamber which allows for lower combustion temperatures in
the range of 320 to 430 C (versus 760 C for non-catalytic oxidizers). These units use
electric coils for startup and temperature maintenance. These units are typically constructed
completely of steel with integrated catalyst units. They do not produce NOx or CO, nor do
they require large amounts of electricity because they run at relatively low temperatures and
they use heat exchangers to pre-heat incoming air. The catalyst must be cleaned
periodically. Also, the catalyst effectiveness may be masked by halogens, metals, non-
organic solvent resins, and other materials. If appropriate materials are used in the
combustion chamber and the electric coils, halogenated solvents can be oxidized.
Direct, gas-fired, catalytic oxidizers are similar to the electric catalytic oxidizers
except that they use gas fired burners, instead of electric coils, for makeup heat. They also
use precious metal catalysts. These oxidizers utilize heat exchangers to pre-heat exhaust air,
which reduces fuel requirements to relatively small amounts. If their catalysts are
contaminated by halogen resins or high boiling organic solvents, the units may produce
some NOx or CO emissions.
10
-------
Carbon adsorption as a technique for organic-sol vent recovery has been used
commercially for several decades. Spray applied coatings contain a mixture of several
organic solvents in order to maximize gloss, transfer efficiency, and other desirable coating
properties. Organic solvent recovery is usually most effective economically and technically
when used with air streams containing a few, expensive organic solvents. In a carbon
adsorption system with steam desorption, carbon beds adsorb organic solvents from the air
stream passing through them. In most cases, one bed is in the adsorption phase while the
second bed is in the steam desorption phase. In the desorption phase, steam is passed
through the carbon to release the collected organic solvent. Once the steam has been passed
through the carbon, it is then condensed and the organic solvent is removed through the
process of settling or distillation. The carbon desorption phase can be performed on site or
the spent carbon can be shipped off-site for regeneration. The efficiency of this type of
system can be very high when there are low organic solvent concentrations in the air
exhausted from the application booths. Advantages of the carbon adsorption/steam
desorption system are that they are relatively inexpensive and have been proven effective
over the years. They can handle a relatively high volume of air (about 30 to 1,400 cubic
meters per minute) efficiently. Also, because the organic solvent is reclaimed there are no
carbon monoxide (CO), carbon dioxide (CO2), or nitrogen oxide (NOx) emissions that are
usually associated with the destruction of used organic solvent in air streams by combustion.
Also, if the recovered organic solvents can be re-used it reduces the demand for production
of additional organic solvent. The disadvantages of these systems result from the difficulty
of separating organic solvents from each other for re-use. Also, if water soluble organic
solvents (i.e., alcohols, etc.) are used, it may be difficult to separate the organic solvents
from water. In addition, carbon does not adsorb all organic solvents. Therefore, the blend
of organic solvents in use must be determined and considered before choosing this type of
system. Another problem with systems of this type is that organic solvent quality can be
degraded while the organic solvent is held on the carbon.
B. Available Controls for VOC Emissions from Cleaning Materials
Pollution prevention measures and emission capture and add-on control systems are
also employed to reduce VOC emissions from cleaning materials used in large appliance
coating facilities.
1. Pollution Prevention Measures
Product substitution/reformulation and work practice procedures are pollution
prevention measures that may be used to decrease VOC emissions from cleaning materials.
Alternative cleaners, such as alcohols and citrus-based cleaners, may be used to reduce VOC
emissions from cleaning operations.
Work practice procedures may also reduce VOC emissions from materials during
cleaning operations. An example of a cleaning specific work practice involves spraying
operations and cleaning. Nozzle maintenance, although often overlooked, is a critical
component of any metal pretreatment system. In order to keep the system running at
maximum efficiency to produce the highest-quality finished product, nozzle maintenance
must become a regular part of system operation. Improperly maintained nozzles decrease
spray impact and distort spray patterns, reducing cleaning efficiency. As a result, more time
will be spent and more chemicals will be used to accomplish cleaning tasks. Learning to
11
-------
identify, solve, and prevent spray nozzle performance problems in a parts washer can cut
spray liquid and energy waste, assure better washer performance, and reduce chances of
equipment damage. The same holds true for coating spray nozzles. Typical cleaning
activities involve organic solvent wipes, dips, and spraying of pure organic solvent which
can contribute to the emissions from a facility. The amount of organic solvent emissions
released from these activities can be minimized by taking actions such as storing cleaning
materials in covered containers, using only the smallest amount of cleaning materials
necessary, and collecting and placing solvent-laden cleaning materials in closed containers
immediately after they are used.
2. Emission Capture and Add-On Control Systems
Carbon adsorption units or oxidizers can be used to control VOC emissions from
cleaning operations as well as coating operations. Large appliance coaters can employ add-
on controls, such as carbon adsorption units or oxidizers, to reduce their VOC emissions
from cleaning operations.
C. Existing Federal State, and Local Recommendations/Regulations
Provided below is a summary of EPA actions, as well as State and local regulations,
that address VOC emissions from large appliance coating processes. In addition, Table 1
outlines these Federal, State and local provisions and the bases for these provisions.
1. The 1977 CTG
The 1977 CTG recommended limiting VOC emissions from each large appliance
coating unit. A coating unit consists of a series of one or more coating applicators and any
associated drying area and/or oven wherein a coating is applied, dried, and/or cured. A
coating unit ends at the point where the coating is dried or cured, or prior to any subsequent
application of a different coating. (Two-step powder coating systems in which the powder
coating is preceded by an adhesion enhancer may be considered as a single coating unit.) It
is not necessary for a coating unit to have an oven or a flash-off area.
For each coating unit, the 1977 CTG recommended a daily volume-weighted average
limit of 0.34 kg/1 (2.8 Ib/gal) of coating, excluding water and exempt compounds, as applied.
The emission limit was based on the use of low VOC content coatings and can be achieved
with coatings which contain at least 62 volume percent solids or any waterborne equivalent.
It was anticipated that this emission limit would result in approximately an 80 percent
reduction in VOC emissions over conventional solvent-borne coatings that contain about 25
volume percent solids. An equivalent reduction could be achieved by use of add-on control
devices such as thermal oxidation or carbon adsorbers. Even greater reductions, 90 percent
and more, could be achieved by conversion to electrodeposited waterborne coatings or
powder coatings. There was no single control technique that was considered best for the
entire industry since the large appliance industry included a wide variety of products. At the
time, it was believed that most facilities would seek to meet future regulations through the
use of low VOC content coatings rather than using to add-on control technologies.
12
-------
2. The 1982 NSPS
The 1982 NSPS applies to coating of large appliance products and parts at facilities
that commence construction, modification, or reconstruction after December 24, 1980. The
NSPS defines a large appliance part as any organic surface-coated metal lid, door, casing,
panel, or other interior or exterior metal part or accessory that is assembled to form a large
appliance product. Parts subject to in-use temperatures in excess of 250°F are not included
in this definition. Large appliance product is defined as any organic surface-coated metal
range, oven, microwave oven, refrigerator, freezer, washer, dryer, dishwasher, water heater,
or trash compactor manufactured for household, commercial, or recreational use. The NSPS
establishes a monthly volume-weighted average VOC limit of 0.90 kg/1 (7.5 Ib/gal) coating
solids deposited for each surface coating operation on a large appliance surface coating line.
3. The 2002 NESHAP
EPA promulgated the large appliance surface coating NESHAP on July 23, 2002.
Since the rule development was conducted within the past five (5) years, it was determined
that the information collected during the rule's development would be consistent with
current large appliance coating facilities.
Per the 2002 NESHAP, large appliance surface coating facilities are likely to be
included under SIC codes 3631, 3632, 3633, 3639, 3582, 3585, and 3589 (excluding special
industry machinery, industrial and commercial machinery and equipment, and electrical
machinery equipment and supplies not elsewhere classified). Typical NAICS codes for this
industry include 335221, 335222, 335224, 335228, 333312, 333415, and 333319 (also
excluding special industry machinery, industrial and commercial machinery and equipment,
and electrical machinery equipment and supplies not elsewhere classified). The large
appliance source category includes facilities that apply coatings to large appliance parts or
products. In the NESHAP, large appliances includes "white goods" such as ovens,
refrigerators, freezers, dishwashers, laundry equipment, trash compactors, water heaters,
comfort furnaces, and electric heat pumps. The source category also includes most heating,
ventilating, and air conditioning (HVAC) equipment intended for any application.
However, the NESHAP did not include in the source category motor vehicle air-
conditioning units, heat transfer coils, and large commercial and industrial chillers.
13
-------
Table 1. Summary of Existing Requirements
Existing Regulation
Emission Limit
Basis for Emission Limit
Large Appliance Coating CTG
(December 1977)
Recommended VOC emission limit
of 2.8 pounds of VOC per gallon of
coating, excluding water and
exempt compounds, as applied
(daily volume-weighted average)
(narrow definition of coating unit)
Calculated based on the use of higher
solids coatings (62 percent solids) with
an assumed VOC density of 7.36
Ib/gal. Associated with a baseline
transfer efficiency of 60 percent.
Large Appliances NSPS
(October 27, 1982)
VOC emission limit of 7.5 pounds
of VOC per gallon of coating solids
deposited from any surface coating
operation on a large appliance
surface coating line (monthly
volume-weighted average) (narrow
definition of coating operation)
Based on the use of higher solids
coatings (62 percent by volume solids)
with an assumed VOC density of 7.36
Ib/gal and a baseline transfer efficiency
of 60 percent.
Large Appliances NESHAP
(July 23, 2002)
Existing sources: HAP emission
limit of 1.1 pounds of organic HAP
per gallon of coating solids used
New sources: HAP emission limit
of 0.18 pounds of organic HAP per
gallon of coating solids used
MACT level of control based on 2000
survey of coating materials used in the
industry
California - South Coast Rule
1107 (Originally adopted
June 1, 1979 with last
amendment January 6, 2006)
VOC emissions limits for the
coating of metal parts and products
(which includes large appliance
coating) of: (1) 2.3 pounds of VOC
per gallon (0.275 kilograms per
liter) of coating, excluding water
and exempt compounds, as applied
for general one component coatings
(air-dried and baked) and general
multi-component baked coatings;
and (2) 2.8 pounds of VOC per
gallon (0.34 kilograms per liter) of
coating, excluding water and
exempt compounds, as applied for
general multi-component air-dried
coating. Includes specific limits for
specialty coatings such as extreme
high gloss, high temperature, and
metallic coatings. Electrostatic
application, flow coat, dip coat, roll
coat, HVLP spray, hand application
methods, or other coating
application method capable of
achieving a transfer efficiency
equivalent or better than that
achieved by HVLP spraying
required.
Similar to the 1977 CTG but using a
coating with 69 percent volume solids
for general one-component (air-dried
and baked) coatings and for general
multi-component baked coatings, 62
percent volume solids for general
multi-component air-dried coatings
and a transfer efficiency of 65 percent
14
-------
Table 1. Summary of Existing Requirements (Continued)
Existing Regulation
Emission Limit
Basis for Emission Limit
California - South Coast Rule
1107 Continued
Exempts coatings and operations
such as stencil coatings, safety-
indicating coatings, touch-up
coatings and application with
hand-held aerosol cans.
Alternative to the emissions limit
and operating equipment
requirement allows the use of
capture and control equipment to
collect at least 90 percent by
weight of the VOC emissions
generated by the sources of VOC
emissions (capture efficiency)
and reduce VOC emissions from
an emission collection system by
at least 95 percent by weight
(control efficiency).
California - Bay Area Regulation
8, Rule 14
(Originally adopted
March?, 1979 with last
amendment October 16, 2002)
Method of coating application
must have a transfer efficiency of
65% or greater. VOC emission
limit for baked coatings of 2.3
pounds per gallon (0.275
kilograms per liter) of coating,
excluding water and exempt
compounds, as applied and for
air-dried coatings of 2.8 pounds
per gallon (0.34 kilograms per
liter) of coating, excluding water
and exempt compounds, as
applied. Includes specific limits
for specialty coatings such as
extreme high gloss, high
temperature, and metallic
coatings.
Similar to the 1977 CTGbut
using a coating with 69 percent
volume solids for baked coatings
and 62 percent volume solids for
air-dried coatings and a transfer
efficiency of 65 percent
State Regulations:
22 State rules specifically for
large appliance coating
operations were identified
VOC emission limit of
2.8 pounds of VOC per gallon of
coating, excluding water and
exempt compounds, as applied, or
an overall emission reduction of
90 percent by utilization of an
add-on control device
1977 CTG
15
-------
The NESHAP's affected source includes all of the activities that involve coatings,
thinners, and cleaning materials used in large appliance coating operations. These activities
include:
1) Surface preparation of the large appliance parts or products;
2) Preparation of coatings for application;
3) Applying the coatings;
4) Flash-off, drying, or curing f the coatings;
5) Cleaning of coating equipment;
6) Storage of coatings, thinners, and cleaning materials;
7) Conveying of these materials; and
8) Handling and conveying of waste materials generated by the coating operation.
For the 2002 NESHAP, EPA selected the pollutants to regulate based on some
assumptions generated during the rule development. Emission data collected during the
development of the rule showed that the primary organic HAP emitted from the surface
coating of large appliances included xylene, glycol ethers, toluene, methylene diphenyl
diisocyanate, and MEK. These compounds accounted for approximately 82 percent of this
category's nationwide organic HAP emissions. However, many other organic HAP are
used, or can be used, in large appliance coatings, thinners, and cleaning materials.
Therefore, the rule regulated emissions of all organic HAP. Although most of the coatings
used in this source category do not contain inorganic HAP, some special purpose coatings
used by this source category were found to contain inorganic HAP such as chromium,
cobalt, lead, and manganese. Emissions of these materials to the atmosphere are minimal
because the facilities in this source category employ either water curtains or dry filters that
remove overspray particles from the spray booth exhaust. At the time, it did not appear that
emissions of inorganic HAP from this source category warranted Federal regulation.
The final rule established different emission limits for existing and new sources. For
an existing source, the organic HAP emissions limits is no more than 0.13 kilograms per
liter (1.1 pounds per gallon) of coating solids used during each compliance (monthly)
period. For a new or reconstructed source, the organic HAP emissions limit is no more than
0.022 kilograms per liter (0.18 pounds per gallon) of coating solids. The limits apply to the
total of all coatings, thinners, and cleaning materials used in coating operations at the
affected source. Existing sources had to be in compliance no later than July 25, 2005. New
or reconstructed sources have to be in compliance by this same date or upon startup,
whichever is later. These HAP emission limits take into account products that contain MEK
even though in December 2005, EPA amended the list of HAP contained in section 112 of
the CAA by removing MEK. It is unclear at this point how MEK being delisted as a HAP
has affected the large appliance coatings formulation. The NESHAP established three
compliance options for meeting the emissions limits.
1) Compliant Material Option - Each coating used in the operation must meet the
limit, and each thinner and cleaning material must contain no organic HAP.
2) Emission Rate Without Add-on Controls Option - The facility may average all of
the coatings, thinners, and cleaning materials together and demonstrate that the
overall emission rate is in compliance with the applicable limit.
16
-------
3) Emission Rate With Add-on Controls Option - This option applies to coating
operations for which add-on controls are used to meet the limit. The facility
must meet certain operating limits for the capture systems and control devices
and follow a work practice plan for material storage, mixing, conveying, and
spills.
4. Existing State and Local VOC Requirements
Every State has incorporated the large appliance coating Federal regulations
described above (1982 NSPS and 2002 NESHAP). In addition, 22 States have specific large
appliance coating regulations. 21 states have adopted the 1977 CTG recommended VOC
emissions limit of 0.34 kilogram per liter (2.8 pounds per gallon) of coating, excluding water
and exempt compounds, as applied. Five (5) States also have equivalent pound of VOC per
gallon of coating solids used emissions limits. Appendix B provides a table which
summarizes the large appliance coating regulations that are specific to a State and/or local
agency within that State.
The California South Coast Air Quality Management District (South Coast) has
adopted limits for large appliance coating that are, in part, more stringent than the 1977 CTG
recommendation. The VOC emissions limits established by the South Coast for the coating
of metal parts and products (which includes large appliance coating) are: (1) 275 grams
VOC per liter (g VOC/1) (2.3 Ib VOC/gal) of coating, excluding water and exempt
compounds, as applied for general one-component coatings (air-dried and baked) and
general multi-component baked coatings; and (2) 340 g VOC/1 (2.8 Ib VOC/gal) of coating,
excluding water and exempt compounds, as applied for general multi-component air-dried
coatings. The South Coast regulation also includes specific limits for specialty coatings such
as extreme high gloss, high temperature, and metallic coatings. The South Coast regulation
specifies the following application methods: electrostatic application, flow coat, dip coat,
roll coat, HVLP spray, hand application methods, or other coating application method
capable of achieving a transfer efficiency equivalent or better than that achieved by HVLP
spraying. Coatings and operations such as stencil coatings, safety-indicating coatings,
touch-up coatings and application with hand-held aerosol cans are exempt from the South
Coast's regulation. As an alternative to the emissions limit and operating equipment
requirement, the South Coast regulation allows the use of capture and control equipment to
collect at least 90 percent by weight of the VOC emissions generated by the sources of VOC
emissions (capture efficiency) and reduce VOC emissions from an emission collection
system by at least 95 percent by weight (control efficiency).
The California Bay Area Air Quality Management District (Bay Area) has also
adopted limits for large appliance coating that are, in part, more stringent than the 1977 CTG
recommendation: (1) 275 grams of VOC per liter (2.3 pounds of VOC per gallon) of
coating, excluding water and exempt compounds, as applied for baked coating; and (2) 340
grams of VOC per liter (2.8 pounds of VOC per gallon) of coating, excluding water and
exempt compounds, as applied for air-dried coating. Like the South Coast regulations, the
Bay Area regulations include specific limits for specialty coatings and exemptions for some
coatings and coating operations. In addition, the Bay Area rule requires the use of coating
application equipment that can meet a 65 percent or greater transfer efficiency. Per the Bay
Area regulation, compliance with the standard's 65 percent or great transfer efficiency can
17
-------
be achieved by properly operated electrostatic application or HVLP spray, flow coat, roller
coat, dip coat including electrodeposition, and brush coat.
VI. Recommended Control Options
Based on a review of the 1977 CTG, the 1982 NSPS, the 2003 NESHAP, and the
current State and local requirements discussed above, we are recommending emission limits
for controlling the VOC emissions from the coatings used by large appliance manufacturing
facilities and work practices to further reduce VOC emissions from coatings as well as to
minimize emissions from cleaning materials used in metal furniture surface coating
processes.
To control VOC emissions from large appliance coatings, we are recommending
three alternatives: (1) emission limits that can be achieved through the use of low-VOC
coatings; (2) equivalent emission limits that can be achieved through the use of low-VOC
coatings or a combination of coatings and add-on controls; and (3) an overall control
efficiency of 90 percent for add-on controls. The low-VOC coatings recommendation
consists of emission limits in terms of mass of VOC per volume of coating, excluding water
and exempt compounds, as applied and the use of specified application methods. The
equivalent emission limit recommendation consists of emission limits in terms of mass of
VOC per volume of coating solids, as applied, and the use of specific application methods.
We estimate that these recommendations will reduce VOC emissions from large
appliance coatings by about 30 percent (a reduction of 1,000 tons of VOC from the
nonattainment area facilities). In our analysis of the impacts of the recommended level of
control, we have assumed that all facilities will choose to utilize the low-VOC coating
materials alternative. We made this assumption for two reasons. First, we believe that
complying low-VOC coating materials are already widely available at a cost that is not
significantly greater than the cost of coating materials with higher VOC contents. Secondly,
the use of add-on controls to reduce emissions from typical spray coating operations would
be a more costly alternative.
For cleaning materials, we are recommending work practices to reduce VOC
emissions. We do not have information available regarding current VOC content to
determine a RACT limit for cleaning materials used in large appliance surface coating
operations. Therefore, we are not recommending the use of a VOC content limit for
cleaning materials. We are also not recommending the application of add-on controls solely
as a means of reducing VOC emissions from cleaning materials. This would be a very
costly alternative because the area to be controlled is quite large and a large volume of air
would need to be captured and directed to a control device. However, any cleaning
activities that occur within a capture device used to control VOC emissions from coating
operations would be controlled by the associated control device.
The following paragraphs summarize our specific recommendations for coating
operations and cleaning materials used in large appliance surface coating operations.
18
-------
A.
Emissions Limits based on Low-VOC Coatings
We are recommending emission limits for one-component and multi-component
general purpose coatings. In addition, we are recommending specific emission limits for
certain specialty coatings. For each of these coating types, we are recommending separate
emission limits for baked and air-dried coatings. Provided below are our recommended
emission limits expressed in terms of mass of VOC per volume of coating, excluding water
and exempt compounds, as applied:
Coating Type
General, One Component
General, Multi-Component
Extreme High Gloss
Extreme Performance
Heat Resistant
Metallic
Pretreatment Coatings
Solar Absorbent
Baked
kg/1
0.275
0.275
0.360
0.360
0.360
0.420
0.420
0.360
Ib/gal
2.3
2.3
3.0
3.0
3.0
3.5
3.5
3.0
Air Dried
kg/1
0.275
0.340
0.340
0.420
0.420
0.420
0.420
0.420
Ib/gal
2.3
2.8
2.8
3.5
3.5
3.5
3.5
3.5
The recommended emission limits can also be expressed in terms of mass of VOC
per volume of coating solids, as applied. A facility could use low-VOC coatings or a
combination of coatings and add-on control equipment on a coating unit to meet the
recommended mass of VOC per volume of coating solids, as applied, limits. Using an
assumed VOC density of 7.36 pounds per gallon, equivalent limits in terms of mass of VOC
per volume of solids, as applied, are as follows:
Coating Type
General, One Component
General, Multi-Component
Extreme High Gloss
Extreme Performance
Heat Resistant
Metallic
Pretreatment Coatings
Solar Absorbent
Baked
kg/1
0.40
0.40
0.61
0.61
0.61
0.80
0.80
0.61
Ib/gal
3.3
o o
J.J
5.1
5.1
5.1
6.7
6.7
5.1
Air Dried
kg/1
0.40
0.55
0.55
0.80
0.80
0.80
0.80
0.80
Ib/gal
3.3
4.5
4.5
6.7
6.7
6.7
6.7
6.7
We are also recommending that the following types of coatings and coating
operations be exempt from our recommended VOC content limits:
Stencil coatings
Safety-indicating coatings
Solid-film lubricants
Electric-insulating and thermal-conducting coatings
19
-------
Touch-up and repair coatings
Coating application utilizing hand-held aerosol cans
We are recommending that all VOC-containing materials (i.e., coatings and thinners)
used by each large appliance surface coating unit are included when determining the coating
unit's emission rate. In addition, we are recommending the use of the following application
methods: electrostatic application, HVLP spray, flow coat, roller coat, dip coat including
electrodeposition, brush coat, or other coating application method capable of achieving a
transfer efficiency equivalent or better than that achieved by HVLP spraying. The
recommendations described above are based on the South Coast's metal parts and products
coating regulation, which includes large appliances.
The VOC content limits can be met by averaging the VOC content of materials used
on a single surface coating unit each day (i.e., daily within-coating unit averaging). We do
not recommend the use of cross-coating unit averaging (i.e., averaging across multiple
coating units) to meet the VOC content limits. However, we have previously provided
guidance on cross-line averaging4. The guidance is directed to State and local agencies that
elect to adopt a discretionary economic incentive programs (EIP) and includes guidance on
the use of cross-line averaging.
B. Optional Add-On Controls for Coating Operations
Should product performance requirements or other needs dictate the use of higher-
VOC materials than those that would meet the recommended emission limit, a facility could
choose to use add-on control equipment to meet an overall control efficiency of 90 percent.
Alternatively, a facility could use a combination of coatings and add-on control equipment
on a coating unit to meet the recommended mass of VOC per volume of coating solids
limits. Add-on devices include oxidizers and solvent recovery systems that, coupled with
their attendant systems to capture the VOC being released at the affected facilities, can
achieve an overall control efficiency of 90 percent. This control option, like the options
noted above, applies to all coatings and thinners applied to large appliances.
C. Work Practices for Coating Operations and Cleaning Materials
In addition to the control options above, this CTG recommends work practices to
further reduce emissions from the coatings as well as to minimize emissions from the
cleaning materials used for large appliance coating operations. Although VOC reductions
achieved by implementing the work practice recommendations may not be quantifiable, we
believe they are beneficial to the overall goal of reducing VOC emissions. We recommend
implementing work practices for solvent storage, mixing operations, and handling
operations for coatings, thinners, cleaning materials, and waste materials. Specifically, we
recommend the following work practices: store all VOC-containing coatings, thinners, and
cleaning materials in closed containers; minimize spills of VOC-containing coatings,
thinners, and cleaning materials; clean up spills immediately; convey any coatings, thinners,
and cleaning materials in closed containers or pipes; close mixing vessels that contain VOC
4 Improving Air Quality with Economic Incentive Programs. U. S. Environmental Protection
Agency. Research Triangle Park, NC. EPA-452/R-01-001. January 2001.
20
-------
coatings and other materials except when specifically in use; and minimize usage of solvents
during cleaning of storage, mixing, and conveying of equipment.
VII. Cost Effectiveness of Recommended Control Options
As previously mentioned, the recommendations in this CTG are similar to the South
Coast regulations governing large appliance coating operations. Unfortunately, the cost-
effectiveness of these regulations was not estimated during those regulations' development.
Therefore, cost-effectiveness estimates for the recommended control levels were determined
based on information collected during the 1977 CTG and the 2002 NESHAP development.
Although the 2002 NESHAP regulates organic HAP, the 2002 NESHAP cost estimates are
relevant to this CTG's recommended levels of control because they are based on the use of
the similar control measures (i.e., product substitution/reformulation and work practices) for
large appliance coatings and cleaning materials as those recommended in this CTG. In
addition, the 2002 NESHAP provides data regarding large appliance coating facilities that
are more current than the 1977 CTG.
During the development of the 2002 NESHAP, it was estimated that no facility
within the industry would install add-on control devices as a result of the standard. The
capital costs and annual operating costs of add-on control devices usually make them less
desirable than other compliance options for reducing VOC emissions from spray coating
operations.
In the 1977 CTG, the cost effectiveness for a medium-sized facility using waterborne
prime and higher solids topcoat was estimated to be $141 per megagram ($128 per ton) of
VOC reduced. This would be approximately $425 per ton in 2006 dollars based on
historical CPI data from www.inflationdata.com. The 2002 NESHAP presented a control
cost of $480,000 for 1,191 tons of HAP reduction from 74 facilities expected to be subject to
the rule ($403 per ton HAP reduced, about $480 per ton in 2006 dollars). For, the
recommendations in this CTG, we therefore estimate a cost-effectiveness of $500 per ton of
VOC reduced. We estimate the total annual cost of the estimated 1,000 tpy of emission
reduction to be $500,000.
21
-------
VIII. References
1. Control of Volatile Organic Emissions from Existing Sources - Volume V: Surface
Coating of Large Appliances. Publication No. EPA-450/2-77-034. U.S.
Environmental Protection Agency, Research Triangle Park, NC. December 1977.
2. Bay Area (California) Air Quality Management District Regulation 8, Organic
Compounds, Rule 14, Surface Preparation and Coating of Large Appliances and
Metal Furniture. Amended October 16, 2002.
3. South Coast (California) Air Quality Management District Regulation XI, Source
Specific Standards, Rule 1107, Coating of Metal Parts and Products. Amended
January 6, 2006.
4. National Emission Standards for Hazardous Air Pollutants (NESHAP) for Source
Category: Large Appliances Surface Coating Operations - Background Information
for Promulgated Standards. EPA-453/R-02-004. U. S. Environmental Protection
Agency, Research Triangle Park, NC. April 2002.
5. Industrial Surface Coating: Appliances - Background Information for Proposed
Standard. EPA-450/3-80-037a. U. S. Environmental Protection Agency, Research
Triangle Park, NC. November 1980.
6. Improving Air Quality with Economic Incentive Programs. U.S. Environmental
Protection Agency. Research Triangle Park, NC. EPA-452/R-01-001. January
2001.
22
-------
Appendix A: 1977 Large Appliance Coating CTG Document
-------
This page intentionally left blank.
-------
United S
Agency
Air
Offio? o( Ağ Quaky
Planning and Standards
Research Triangle Park MC 2771 1
EPA- 460/2 77-034
OAQPS No. "I 2-08S
December 197?
OAQPS Guideline Series
Control of Volatile
Organic Emissions from
Existing Stationary
Volume V: Surface
Coating of
Appliances
-------
This page intentionally left blank.
-------
Appendix B: Summary of State-Specific Large Appliance
Coating Regulations
-------
This page intentionally left blank.
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
AL
Jefferson
Application area(s), flash-off area(s), and
oven(s) of coating lines involved in prime,
single, or topcoat coating operations. Does
not apply to the use of quick-drying
lacquers for repair of scratches and nicks
that occur during assembly, provided that
the volume of coating does not exceed 757
liter/yr (200 gal/yr).
0.34 kg/liter (2.8 Ib/gal) of
coating, excluding water,
delivered to the coating
applicator from prime, single,
or topcoat coating operations.
AZ
Maricopa
Application of coating, coating
preparation/mixing at the facility applying
the coating, & the cleanup of coating
application equipment. Does not apply to
coatings with VOC content, minus exempt
compounds, of less than 0.15 Ib VOC/gal
(18 g/liter) nor to solvents having a VOC
content of material less than 0.15 Ib
VOC/gal.
2.8 Ib/gal or 0.34 kg/liter of
coating (minus water)
For coating containing more than 2 Ib VOC/gal
(240 g/liter) minus exempt compounds:
1. Low-pressure spray gun
2. Electrostatic system
3. Atomizing system by hydraulic pressure,
including "airless" and air-assisted airless"
4. Non-atomizing or non-spraying applications
such as dipping, rolling, or brushing
5. Any method approved by the Federal EPA
Administrator and Control Officer having a
transfer efficiency of 65% or greater
CA
Bay Area
Does not apply to the use of any coating
used in volumes less than 75.7 liters/yr (20
gal/yr) (facility limited to 208.1 liters or 55
gallons total coating/yr). Also does not
apply to surface preparation of electrical
and electronic components, stripping of
cured inks, coatings and adhesives or
cleaning of resin, coating, ink and adhesive
mixing, molding and application equipment,
or surface preparation associated with
research and development operations;
performance testing to determine coating,
adhesive or ink performance; or testing for
QA/QC purposes.
Method of coating application
must have a transfer efficiency
of 65% or greater and then a
VOC emission limit for baked
coatings of 2.3 Ib/gal
(275 g/L) and for air-dried
coatings of 2.8 Ib/gal
(340 g/L) of coating,
excluding water. Includes
specific limits for specialty
coatings such as extreme high
gloss, high temperature, and
metallic coatings.
-------
State
CO
County/Area
South Coast
VOC Limit Applies To
Applies to all metal coatings operations
except those performed on aerospace
assembly, magnet wire, marine craft, motor
vehicle, metal container, and coil coating
operations. This rule does not apply to the
coating of architectural components coated
at the structure site or at a temporary
unimproved location designated exclusively
for the coating of structural components.
Coating line; prime, single or topcoat
application area, flash-off area, and oven
VOC Limit
2.3 Ib/gal (0.275 kg/liter) of
coating, excluding water and
exempt compounds, as applied
for general one component
coatings (air-dried and baked)
and general multi-component
baked coatings; and 2.8 Ib/gal
(0.34 kg/liter) of coating,
excluding water and exempt
compounds, as applied for
general multi-component air-
dried coating. Includes
specific limits for specialty
coatings such as extreme high
gloss, high temperature, and
metallic coatings.
Electrostatic application, flow
coat, dip coat, roll coat, HVLP
spray, hand application
methods, or other coating
application method capable of
achieving a transfer efficiency
equivalent or better than that
achieved by HVLP spraying
required.
0.34 kg/liter coating or 2.8
Ib/gal coating (minus water)
Emission Limitation Achieved By
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
DE
Any large appliance coating unit. Does not
apply to a facility whose actual emissions
w/out control devices from all large
appliance coating units w/in the facility are
<6.8 kg VOC/day (15 Ib VOC/day) or the
use of quick-drying lacquers for repairs of
scratches & nicks that occur during
assembly, provided that the volume of
coating does not exceed 0.95 liter/any 8-hr
period (0.25 gal/any 8-hr period).
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water &
exempt compounds)
1. Installing and operation a capture system
2. Installing and operation a control device
3. Determining the overall emission reduction
efficiency for each day needed to demonstrate
compliance
4. Demonstration each day that the overall
emission reduction efficiency achieved for that
day is greater than or equal to the overall
emission reduction efficiency required for that
day
FL
Application areas, flash-off areas, and ovens
of coating lines involved in prime, single, or
topcoat coating operations.
0.34 kg/liter (2.8 Ib/gal) of
coating (excluding water)
1. Application of low solvent content coating
technology
2. Incineration, provided that 90% of the VOC
which enter the incinerator are oxidized to
carbon dioxide and water
IL
Does not apply to use of quick-drying
lacquers for repair of scratches & nicks that
occur during assembly, provided that the
volume of coating does not exceed 0.95
liter/any one 8-hr period (1 qt/any 1 8-hr
period)
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water &
exempted compounds)
IN
Coating application (prime, single, or
topcoat coating operations). Does not apply
to use of quick-drying lacquers for repair of
scratches & nicks that occur during
assembly (limited to 1 gal in an 8-hr
period).
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water)
-------
State
KY
MD
MI
County/Area
VOC Limit Applies To
Applies to facilities commenced before
6/29/79 located in a ozone nonattainment
county. Does not apply to any affected
facility:
1) if the VOC content of the coating is
<0.34 kg/liter (2.8 Ib/gal) (minus water or
exempt solvent)
2) repair coating operations
3) total VOC emissions are less than or
equal to 3 Ib/hr actual, 15 Ib/day actual, or
10 ton/yr potential before control
4) low-use coatings if plantwide
consumption of these coatings in the
aggregate is less than or equal to 55 gals
during the previous 12 months
Does not apply to use of quick-drying
lacquers for repair of scratches & nicks that
occur during assembly.
The primer surface or topcoat coating
includes an anti-chip, blackout, or spot
primer coating if this coating is applied as
part of the primer surface or topcoat coating
operation. Does not apply to coatings that
are used for the repair of scratches & nicks.
Exceptions also include coating lines w/in a
stationary source with actual VOC
emissions <100 Ib/day or 2,0000 Ib/month
and excludes low-use coatings that total 55
gallons or less per rolling 12-month period.
VOC Limit
No facility discharge of VOC
into the atmosphere more that
15% by weight of the VOC
net input into the facility
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water)
2.8 Ib VOC/gal of coating
(minus water) or 7.5 Ib
VOC/gal of applied coating
solids
Emission Limitation Achieved By
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
NJ
Surface coating operation located at a major
VOC facility having the potential to emit 3
Ib VOC/hr or more.
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water)
May apply to alternative maximum allowable
VOC limit per volume of surface coating
formulation provided that the surface coating
formulation is applied at a transfer efficiency of
greater than 60 percent.
NC
Application area(s), flashoff area(s), and
oven(s) of coating lines involved in prime,
single, or topcoat coating operations. Does
not apply to the use of quick-drying
lacquers for repair of scratches and nicks
that occur during assembly, if the volume of
coating does not exceed 1 qt in any 8-hr
period.
4.5 IbVOC/gal of solids
delivered to the coating
applicator from prime, single,
or topcoat coating operations.
If controlled by approved air
pollution control equipment,
the limit is 2.8 Ib VOC/gal of
coating (excluding water &
exempt compounds).
OH
Prime coat, single coat or topcoat coating
line, as follows:
(a) in 24 counties [listed in OAC rule 3745-
21-09(A)(1)], to existing and new coating
lines;
(b) in the other 64 counties, to any new
coating line and to existing and new coating
lines at a facility with potential to emit
equal to or greater than 100 tons VOC per
year.
A new coating line is a coating line for
which construction of modification
commenced on or after October 19, 1979.
The emission limitation does not apply to
the use of quick drying lacquers for repair
of scratches and nicks that occur during
assembly, provided that the maximum
usage of such lacquers does not exceed one
quart in any eight hour period.
2.8 Ib VOC/gal of coating
(excluding water & exempt
solvents) or, if control system
is employed, 4.5 Ib VOC/gal
of solids
(a) complying coatings, or
(b) control system that meets either 4.5 Ibs
VOC/gal solids or an overall 81% reduction
with a control device efficiency of at least 90%,
or
(c) an alternative emissions limitation based
upon a "tested" transfer efficiency greater than
60%.
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
OR
Does not apply to sources whose potential
to emit from coating of VOC are <10 tpy
(or 3 Ib VOC/hr or 15 Ib VOC/day actual)
or research facilities.
2.8 Ib/gal (excluding water &
exempt solvents)
1. Application of low solvent content coating
technology
2. Incineration, provided that 90% of the VOC
which enter the incinerator are oxidized to
carbon dioxide and water
3. Equivalent means of VOC removal.
Meaning it must be approved by proper
authority (Dept. of Env. and Nat. Res, or EPA)
RI
Does not apply to the use of quick drying
lacquers for repair of scratches & nicks that
occur during assembly, provided that the
volume of coating does not exceed 0.25 gals
in any one 8-hr period.
2.8 Ib VOC/gal of coating
(minus water) or 4.52 Ib
VOC/gal of solids
Compliance with emission limitation shall be
achieved through:
1. Installation of an approved control system
such that the total emission reduction is 95% or
greater over uncontrolled VOC emissions
2. Coating reformulation such that the
emission limitation is met for all coatings
3. Installation of control equipment to reduce
emissions to the equivalent of the emission
limitations as calculated on a solids applied
basis
4. Use of daily-weighted averaging
5. An alternative, approved equivalent method
of control
SC
Applies to the prime, single or topcoat from
a coating application system. Does not
apply to the use of quick-drying lacquers for
repair of scratches & nicks that occur during
assembly, provided that the volume of
coating does not exceed 1 qt (0.95 liter) in
any one 8-hr period.
2.8 Ib/gal (0.34 kg/liter) of
coating (excluding water &
exempt solvents)
1. Application of low solvent content coating
technology
2. Incineration, provided that 90% of the
nonmethane VOC which enter the incinerator
are oxidized to CO2 and water
3. Carbon bed solvent recovery system
4. Alternative controls as allowed in Section I,
PartC
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
TN
Does not apply to the use of quick-drying
lacquers for repair of scratches & nicks that
occur during assembly, provided that the
volume of coating does not exceed 0.95 liter
(0.25 gal) in any one 8-hr period and any
large appliance coating line w/in a facility:
1) in Davidson, Rutherford, Sumner,
Williamson, or Wilson County whose actual
emissions w/our control are <6.8kg (15 Ib)
VOC per day or whose max emissions from
all large appliance coating lines are <10 ton
VOC/yr
2) in Hamilton or Shelby County whose
potential VOC emissions from all large
appliance coating lines are <25 ton VOC/yr
3) in any other county whose potential VOC
emissions from all large appliance coating
lines are <100 ton VOC/yr
0.34 kg/liter (2.8 Ib/gal) of
coating (excluding water &
exempt compounds)
TX
Beaumont/Port
Arthur
Dallas/Fort Worth
El Paso
Houston/Galveston
Gregg County
Nueces County
Victoria County
VOC emissions from the application, flash-
off, and oven areas during the coating of
large appliances (prime and topcoat, or
single coat).
2.8 Ib/gal (0.34 kg/liter) of
coating (minus water &
exempt solvent) delivered to
the application system
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
UT
Application areas, flash-off areas, and ovens
of coating lines involved in prime, singe or
top coating operations.
0.34 kg/liter (2.8 Ib/gal) of
coating (excluding water &
exempt solvents) or 4.5 Ib
VOC/gal solids
1. Application of low solvent content
technology
2. Incineration, provided that 90% of the
nonmethane VOC which enter the incinerator
are oxidized to CO2 and water
3. Use of water-borne electrodeposition
4. Use of water-borne spray, dip or flowcoat
5. Use of powder
6. Use of higher solids spray
7. Carbon adsorption
WA
The operation of a coater and dryer, that
may serve one or more process lines, shall
comply if the uncontrolled emissions of
VOC from the coater, flash-off areas, and
dryer would be >18 kg (40 Ib) in any given
24-hr period. The emission limits and
uncontrolled emission quantity shall include
the additional quantity of emissions from
the dryer during the 12-hr period after the
application of the coating.
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water)
WV
Does not apply to any coating line w/in a
facility whose actual emissions w/out
control from all large appliance coating
lines w/in the fenceline are <6.8 kg (15 Ib)
VOC/day or the use of quick-drying
lacquers for repair of scratches & nicks that
occur during assembly, provided that the
volume of coating does not exceed 0.95 liter
(0.25 gal) in any one 8-hr period.
0.34 kg/liter (2.8 Ib/gal) of
coating (minus water &
exempt compounds) as applied
As an alternative to the emission limit:
1. Installation and operation of a capture
system
2. Installation and operation of a control device
3. Determination each day of the overall
emission reduction efficiency needed to
demonstrate compliance
4. Demonstration each day that the overall
emission reduction efficiency achieved for that
day is greater than or equal to the overall
emission reduction efficiency required for that
day
-------
State
County/Area
VOC Limit Applies To
VOC Limit
Emission Limitation Achieved By
WI
Application areas, flash-off areas, and ovens
of coating lines involved in single, prime or
topcoat coating operations. Does not apply
to the use of quick-drying lacquers for
repair of scratches & nicks that occur during
assembly, provided that the volume of
coating does not exceed 0.95 liter (1 qt) in
any one 8-hr period for any appliance
coating line.
0.34 kg/liter (2.8 Ib/gal) of
coating (excluding water)
delivered
-------
United States Office of Air Quality Planning and Standards Publication No. EPA 453/R-07-004
Environmental Protection Sector Policies and Programs Division September 2007
Agency Research Triangle Park, NC
------- |