PRELIMINARY INDUSTRY CHARACTERIZATION:
SURFACE COATING OF PLASTIC PARTS AND PRODUCTS
Coatings and Consumer Products Group
Emission Standards Division
Office of Air Quality Planning and Standards
U.S. Environmental Protection Agency
Research Triangle Park, North Carolina 27711
September 1998
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TABLE OF CONTENTS
Section Page
1.0 OVERVIEW OF INITIAL PHASE AND NEXT STEPS FOR
MACT DEVELOPMENT 1-1
2.0 SUMMARY OF THE INITIAL PHASE OF DATA COLLECTION 2-1
2.1 EXECUTIVE SUMMARY 2-1
2.2 DATA COLLECTION ACTIVITIES 2-3
2.2.1 Goals 2-3
2.2.2 Sources 2-3
2.3 STAKEHOLDER PARTICIPATION 2-9
2.3.1 Stakeholder Members 2-9
2.3.2 Stakeholder Meetings 2-11
2.3.3 Stakeholder Subgroups 2-12
3.0 DESCRIPTION OF THE SURFACE COATING OF PLASTIC PARTS
SOURCE CATEGORY 3-1
3.1 INDUSTRY PROFILE 3-2
3.1.1 Overview of the Plastic Parts Coating Industry 3-2
3.1.2 Industry Sector Descriptions 3-4
3.2 COATING PROCESS DESCRIPTION 3-7
3.2.1 Typical Surface Coating Processes 3-8
3.2.2 Contract Coaters 3-11
3.2.3 Application Technologies 3-11
3.2.4 Ancillary Operations 3-13
3.3 EMISSIONS CHARACTERIZATION AND CONTROL 3-14
3.3.1 Emissions Characterization 3-14
3.3.2 Control Technologies 3-18
3.4 SOURCE CATEGORY SCOPE AND OVERLAP 3-19
3.4.1 Scope 3-20
3.4.2 Overlap with Other Source Categories 3-20
3.4.3 Overlap With Existing Rules 3-24
3.5 SUMMARY OF EXISTING FEDERAL AND STATE
REGULATIONS 3-25
3.5.1 Federal Rules (Business Machines NSPS) 3-25
3.5.2 State Rules 3-26
4.0 REFERENCES 4-1
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Section
Appendix A
Appendix B
Appendix C
Appendix D
Appendix E
Appendix F
Appendix G
TABLE OF CONTENTS (Continued)
Definition of Terms
Synopsis of Alternative Control Techniques Document for Surface Coating
of Plastic Parts
Stakeholders Meeting Summaries
Regulatory Subgroup and Small Business Subgroup Meeting Summaries
New Source Performance Standard for Surface Coating of Plastic Parts for
Business Machines
Summary of State Rules
Comments Received
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LIST OF TABLES
Tahle Page
2-1 STANDARD INDUSTRIAL CLASSIFICATION CODES FOR SURFACE
COATING OF PLASTIC PARTS 2-5
2-2 SOURCE CATEGORY CLASSIFICATION CODES FOR SURFACE COATING
OF PLASTIC PARTS 2-6
2-3 PRIORITY STATES FOR INFORMATION COLLECTION 2-8
2-4 PARTICIPATING TRADE ASSOCIATIONS 2-10
3-1 POTENTIAL OVERLAPPING SOURCE CATEGORIES 3-22
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1.0 OVERVIEW OF INITIAL PHASE AND
NEXT STEPS FOR MACT DEVELOPMENT
Under section 112(d) of the Clean Air Act (the Act), the U.S. Environmental Protection
Agency (EPA) is developing national emission standards for hazardous air pollutants (NESHAP)
for the plastic parts surface coating source category. The EPA is required to publish final
emission standards for hazardous air pollutant (HAP) emissions from the plastic parts source
category by November 15, 2000. For this category, national volatile organic compound (VOC)
rules or control techniques guidelines (CTG) under section 183(e) are being developed on a
similar schedule.
The Act requires that the emission standards for new sources be no less stringent than the
emission control achieved in practice by the best controlled similar source. For existing sources,
the emission control can be less stringent than the emission control for new sources, but it must be
no less stringent than the average emission limitation achieved by best performing 12 percent of
existing sources (for which the EPA has emissions information). The NESHAP are commonly
known as maximum achievable control technology (MACT) standards.
The MACT standards development for the plastic parts industry began with a Coating
Regulations Workshop for representatives of EPA and interested stakeholders in April 1997 and
continues as a coordinated effort to promote consistency and joint resolution of issues common
across nine coating source categories.1 The first phase was one in which EPA gathers readily
available information about the industry with the help of representatives from the regulated
industry, State and local air pollution agencies, small business assistance providers, and
environmental groups. The goals of the first phase were to either fully or partially:
1 The workshop covered eight categories: fabric printing, coating and dyeing; large
appliances; metal can; metal coil; metal furniture; miscellaneous metal parts; plastic parts; and
wood building products. The automobile and light duty truck project was started subsequently.
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Understand the coating process,
Identify typical emission points and the relative emissions from each,
Identify the range(s) of emission reduction techniques and their effectiveness,
Make an initial determination on the scope of each category,
Determine the relationships and overlaps of the categories,
Locate as many facilities as possible, particularly major sources,
Identify and involve representatives for each industry segment,
Complete informational site visits,
Identify issues and data needs and develop plan for addressing them,
Develop questionnaire(s) for additional data gathering, and
Document results of the first phase of regulatory development for each category.
The information summarized in this document can be used by States that may have to
make case-by-case MACT determinations under sections 112(g) or 112(j) of the Act. The initial
phase of the regulatory development focused primarily on literature and database searches,
stakeholder contact, and site visits. The main goal of the initial phase of data collection was to
establish a foundation necessary for further MACT development by gaining an understanding of
the various coating processes and identifying typical emission points and emission reduction
techniques. This document represents the conclusion of that phase of rule development.
This document includes a description of the emission control technologies EPA identified
that are currently used in practice by the industry and that could serve as the basis of MACT.
Within the short time-frame intended for this initial phase, however, only limited data were
collected. The information summarized in this memorandum was collected prior to July 31, 1998.
Additional information will be collected and considered before the plastic parts surface coating
standards are promulgated.
During the next phase, EPA will continue to build on the knowledge gained to date and
proceed with more focused investigation and data analyses. We will also continue our efforts to
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coordinate cross-cutting issues. We will continue to identify technical and policy issues that need
to be addressed in the rule making and enlist the help of the stakeholders in resolving those issues.
Questions or comments on this memorandum should be directed to Bruce Moore
(EPA/OAQPS) at 919-541-5460 or at moore.bruce@epamail.epa.gov.
Section 2.0 summarizes this phase of regulatory development, lists the data collection
activities, and describes the stakeholder participation. Section 3.0 contains a description of the
plastic parts and products surface coating source category, and it includes the following: a profile
of the industry, a description of the coating processes, characterization of emissions and control
technologies, a discussion of source category scope, and a summary of existing Federal and State
regulations. Section 4.0 lists the references cited in this document. Also, note that appendix A
contains a list of defined terms. This list is for the purposes of this document only and it should
not be considered binding or final in any regulatory sense.
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2.0 SUMMARY OF THE INITIAL PHASE
OF DATA COLLECTION
2.1 EXECUTIVE SUMMARY
During the initial phase of data collection, EPA gained an understanding of applicable
control techniques, including add-on control devices such as thermal incinerators and pollution
prevention measures such as coating reformulation. As a result, EPA identified facilities to survey
and industry segments, and characterized the processes and emission points. This process has
raised issues of scope and overlap with other regulations for further investigation.
The EPA's data collection efforts resulted in identification of approximately 500 plastic
part coating facilities. The EPA was not able to determine how many of the identified sources are
major sources. Data collected from database searches, State and local air pollution control
agencies, site visits, the Internet, and stakeholder input suggest four distinct industry segments for
purposes of setting the MACT floor. These include the following:
Automobile and light duty truck parts,
Heavy duty truck parts,
Business machine parts, and
Miscellaneous parts.
The EPA has identified potential overlap between the plastic parts surface coating source
category and existing Federal rules or the other surface coating rules under development. These
potentially overlapping Federal rules include:
Miscellaneous Metal Parts Surface Coating NESHAP,
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Boat Manufacturing NESHAP,
Reinforced Plastic Composites Manufacturing NESHAP,
Automobile And Light Duty Truck Assembly Coating NESHAP,
Large Appliances NESHAP,
Metal Furniture NESHAP,
Miscellaneous Industrial Adhesives NESHAP,
Aerospace NESHAP,
National Emission Standards For Wood Furniture Manufacturing, And
National VOC Emission Standards For Automobile Refinish Coatings.
The EPA does not intend to cover operations under the plastic parts surface coating
NESHAP that are already subject to emission reductions under another NESHAP.
The EPA is considering whether the scope of the source category needs to include
co-located ancillary operations necessary to the surface coating process (such as surface
preparation with solvent containing materials, coating storage and mixing operations, and solvent
use in equipment clean-up). The issue of considering these ancillary operations only if they are
co-located with surface coating operations has yet to be addressed. In addition, EPA is
considering whether the scope should include treatment of non-traditional or special-case coating
operations, such as adhesives application or touch-up coating.
The EPA identified characteristics of the industry that may impact determination of
MACT. Specifically, the rule may need to focus on the systems of compatible coatings so that,
for example, it does not require a base coat that is incompatible with a top coat. In addition, the
rule may need to address the dependency of the coating selection on the substrate type, part
characteristics, coating application methods, and performance specifications of the final part.
The next phase of regulatory development will focus on data collection through an
industry-wide survey and additional site visits. The continuing data collection will be focused on
providing the data necessary to address the issues identified during the initial data gathering
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process. This data will then be used to establish the MACT floor and to evaluate potential control
options that are more stringent than the floor. The EPA encourages the continuing participation
by stakeholders during the MACT process.
2.2 DATA COLLECTION ACTIVITIES
2.2.1 Goals
During the initial phases of the data collection process, it was important to develop an
understanding of the various coating processes and to identify typical emission points and
emission reduction techniques. The data collection goals set by EPA focused on establishing a
foundation needed for MACT development (understanding emission characteristics and evaluating
the level of control in the industry). Some general information needs were identified early in the
process, including:
Determining current applicable coating standards and means of compliance,
Identifying a significant portion of the affected industry facilities, and
Characterizing the wide variety of coatings (including adhesives, sealants, and
caulks) in use.
To characterize the multitude of coatings in use in the industry, EPA established the
objective to gain an understanding of the practical and site-specific constraints relevant to the
coatings applied and to the emission controls (such as process time and space requirements,
finished product quality and appearance, and variability in the size, shape, and other
characteristics of the parts coated). Understanding the coating techniques, types and amounts of
coatings used, emission points, and any VOC and HAP emission reduction technologies and
control technologies was identified by EPA as a goal of the data collection effort.
2.2.2 Sources
The EPA's Alternative Control Techniques (ACT) document, Surface Coating of
Automotive/Transportation and Business Machine Plastic Parts, provided background
information and served as a starting point for the data collection activities.1 The ACT document
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was completed in 1994 and describes the industry as it existed in the early 1990's. (See
appendix B for a synopsis of the ACT document.) Much of EPA's effort in data collection
consisted of updating the ACT document to reflect changes since it was written. The EPA
conducted a literature search of current books, trade journals, engineering handbooks, industry
and trade association home pages on the Internet, and other EPA surface coating documents, in
addition to consulting the following sources of information:
EPA, State, and local air pollution databases,
State and local air pollution control agencies,
Site visits, and
Internet information collection.
Databases. The EPA collected available information on the plastic parts surface coating
industry from several databases. The EPA used the Standard Industrial Classification (SIC) and
Source Category Classification (SCC) Codes listed in Tables 2-1 and 2-2, respectively, in the
searches of databases organized by SIC and/or SCC Code. (As discussed in the bullets that
follow this paragraph, database searches by SIC Code were of limited usefulness.) None of these
databases provided a complete emissions profile of the plastic parts coating industry. The search
did provide initial indications of some of the chemical species emitted and their magnitudes, as
well as the names and locations of plastic parts coating facilities. The EPA searched for
information in the following databases:
Aerometric Information Retrieval System (AIRS) The EPA searched this EPA
database system for process descriptions and HAP and VOC emissions data on the
plant level and on the individual process level. Plant level data were obtained from
AIRS by SIC Code. These data proved to be of limited use for the plastics coating
industry because there are no codes for secondary operations of coating plastics.
A facility that manufactures plastics, but does not coat the substrate, will likely use
an SIC Code for the plastics manufacturing process, as will a facility that performs
both operations.
And although EPA also obtained data from AIRS on an 8-digit SCC Code basis
(individual industrial processes), EPA could not compare process data from AIRS
among the identified facilities because of a lack of consistency in process naming
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TABLE 2-1. STANDARD INDUSTRIAL CLASSIFICATION CODES FOR
SURFACE COATING OF PLASTIC PARTS
SIC Code1
Includes Manufacturing of:
3086
Plastic foam products
3089
Plastic products not elsewhere classified
3537
Industrial trucks, tractors & trailers
3571
Electronic computers
3573
Computer terminals
3577
Computer peripheral equipment
3578
Calculating and accounting machines
3579
Office machines
3643
Current carrying wiring devices
3647
Vehicular lighting equipment
3711
Motor vehicles and passenger car bodies
3713
Trucks and bus bodies
3714
Motor vehicle parts and accessories
3715
Truck trailers
3716
Motor homes
3751
Motorcycles, bicycles, and parts
3799
Transportation equipment
3821
Laboratory apparatus and furniture
3931
Musical instruments
3942
Dolls and stuffed toys
3944
Games, toys, children's vehicles
3949
Sporting and athletic goods
3961
Costume jewelry and novelties
3993
Signs and advertising specialties
1 Searches by SIC Code proved to be of limited use for the plastics coating industry because there are no
codes for secondary operations of coating plastics. A facility that manufacturers plastics, but does not
coat the substrate, will likely use an SIC Code for the plastics manufacturing process. The same code
will likely be used by a facility that performs both operations.
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TABLE 2-2. SOURCE CATEGORY CLASSIFICATION CODES FOR
SURFACE COATING OF PLASTIC PARTS
SCC Code
Includes:
402-xxx Surface coating operations
402-001 through 402-007 Surface coating application - general
402-008
402-009
402-016
402-022
Coating ovens
Thinning solvent - general
Automobile and light duty trucks surface coating
Plastic parts surface coating
Area sources:
A24-01xxx
A24-01035
A24-01055
A24-01065
A24-01070
A24-01090
A24-01990
Solvent utilization, surface coating
Plastic products surface coating
Machinery and equipment surface coating
Electronic and other electrical equipment surface coating
Motor vehicles surface coating
Miscellaneous manufacturing surface coating
All surface coating categories
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schemes. However, the EPA was able to extract facility names and contact
information for facilities that are likely to be coating plastic parts, but was unable
to obtain consistent emissions data.
Toxic Release Inventory (TRI) The TRI system contains data from individual
plants on estimated annual releases for the list of chemicals regulated under
SARA Title III section 313. Since TRI identified processes by SIC Code, it has
the same limitations as AIRS. In addition, the TRI database only contains TRI
reportable compounds, which does not include all HAP and VOC species, and it
only provides facility-wide emissions estimates. The TRI database was used to
identify facilities reporting SIC Codes which are commonly used by plastic parts
coating facilities.
Source Test Information Retrieval System fSTIRSY From the STIRS database,
the EPA extracted source test reports from State and local air pollution control
agencies. The information was obtained for various industrial processes. The
"Evaporative Loss Sources" list for the Industrial Surface Coating category was
searched for information on plastic parts coating facilities. The test data did not
provide emissions estimates for either the facility or for the coating processes, nor
did they provide descriptions of the coating operations. The EPA was able to use
the STIRS reports to identify some additional facilities that may perform surface
coating of plastic parts.
ENFLEX. The EPA used the ENFLEX database, maintained and updated
annually by Information Handling Services Environmental Information, Inc., to
extract the full text of current environmental regulations. The EPA obtained
Federal and State rules, which were then searched to locate States that have
specific coating regulations. Discussion of relevant Federal and State rules is
contained in section 3.0 of this document.
State and Local Agencies. Through the database searches, EPA identified several States
where plastic part coating operations are concentrated, thus allowing prioritization of
States from which to collect information. Table 2-3 shows the States with large numbers
of plastic coating facilities. The EPA contacted State and local air pollution control
agencies in these areas. The primary contribution from the State and local agencies was
identification of plastic coating facilities (including names, locations, and coating process
descriptions) and suggestions of facilities to visit.
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TABLE 2-3. PRIORITY STATES FOR
INFORMATION COLLECTION
California
Michigan
Minnesota
Florida
Illinois
New York
Indiana
Ohio
Massachusetts
Texas
Several State and local air pollution control agencies also provided operating permit
(Title V) applications to facilitate site visits and the development of an industry-wide
questionnaire. Further, seven State agencies performed database searches to provide EPA with
the locations and contact information for additional plastic parts coating facilities, and in some
cases, emissions information that was not obtained from the EPA's database searches.
By contacting these agencies EPA also obtained the most current applicable regulations
and information on current control techniques. To date, 13 State and local agencies have enacted
plastic coating regulations. Discussion of relevant State and local regulations is contained in
section 3.0 of this document.
Site Visits. To date, five site visits were conducted to gather information for
characterizing the industry and to observe current coating practices. The sites were selected
because they represented differing production processes, coating operations, and emission
sources. The EPA visited three heavy duty truck manufacturing facilities and two miscellaneous
plastic parts coating facilities.
Choosing the heavy duty truck manufacturers was based on comments from the Truck
Manufacturer's Association at the first stakeholder meeting. They stated that heavy duty trucks
have coating processes and coating performance requirements unique to the industry. Therefore,
EPA toured representative facilities to gain further insight about these issues. The site visits
revealed several industry specific factors that may affect the feasibility of controls for this segment
of the industry, including:
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Metal and plastic cab components are often coated on the same lines with the same
coatings,
A large number of customized colors are used, and
The industry has stringent durability requirements for its coatings.
The EPA arranged site visits to two facilities that coat miscellaneous plastic parts to learn
more about how the coating process can be flexible enough to accommodate many different types
of parts. At the same time, EPA would learn more about the operations at smaller, contract
coating facilities. Visits to these facilities demonstrated that there are unique, industry specific
factors for this sector as well, because of the wide range of parts coated, varying specifications by
the customer as to which coatings will be used, and the need for highly flexible process
capabilities.
2.3 STAKEHOLDER PARTICIPATION
2.3.1 Stakeholder Memhers
The stakeholders for the plastic parts surface coating regulatory development represent
not only plastic part coaters but also State and local air pollution control agencies, State small
business ombudsmen, and coating formulators and manufacturers. The stakeholder participants
are listed in the stakeholder meeting notes, which are included as appendix C.
Industry trade associations were invited to participate in the plastic parts coating
stakeholder meetings. Each trade association was asked to notify their members of the
opportunity to become involved as well. Participating trade associations are listed in Table 2-4.
In addition to the industry trade associations, EPA contacted State and Territorial Air
Pollution Program Administrators (STAPPA) and Association of Local Air Pollution Control
Officials (ALAPCO) and asked them to notify air quality program managers about participating.
Further, since coatings are likely to be manufactured by businesses other than those applying the
coatings, it was important to include coating formulators and manufacturers as stakeholders in the
information gathering efforts. The National Paint and Coatings Association (NPCA) represents
most coating manufacturers and has been an active participant.
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TABLE 2-4. PARTICIPATING TRADE ASSOCIATIONS
Association
Acronym
Representing
Adhesive and Sealant Council ASC
American Automobile AAMA
Manufacturers Association
Association of International AIAM
Automobile Manufacturers
Chemical Manufacturers CMA
Association
Electronic Industry EIA/CEMA
Association/Consumer
Electronics Manufacturers
Association
National Paint and Coatings NPCA
Association
Society of Plastic Engineers SPE
Society of the Plastic Industry SPI
Truck Manufacturers Association TMA
North American adhesive and sealant manufacturers and industry suppliers.
Chrysler Corporation, Ford Motor Company, General Motors Corporation.
U.S. subsidiaries of the international automobile companies.
Chemical manufacturing companies and raw material suppliers.
EIA represents U.S. electronics manufacturing companies, including small manufacturers
of electronic parts, as well as multinational corporations that design and manufacture
complex systems used by industry, defense, and consumers. CEMA is a sector trade
association within EIA whose primary members are U.S. consumer electronic
manufacturers.
Paint and coatings manufacturers, raw materials suppliers, and distributors.
All areas of the plastics industry worldwide, including the manufacturer of medical
plastics, automotive plastics, and composites, moldmakers, decorating and assembly, and
recycling.
All segments of the plastics industry in the U.S.: plastic processors, raw material
suppliers, machinery manufacturers, and moldmakers.
Manufacturers of medium- and heavy-duty trucks (weight classes 6 through 8) in the U.S.:
Freightliner Corporation, General Motors Corporation, Mack Trucks, Inc., Navistar
International Transportation Corporation, PACCAR, Inc., and Volvo GM Heavy Truck
Corporation.
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There is a large and diverse population of small and/or specialized coaters in this source
category. These coaters are not necessarily represented by one particular trade organization, and
therefore, efforts were made to include others in the regulatory development process. Contacts
made through the Internet and State agency mailing lists have also been used to locate small
businesses. Contact with small businesses will continue to be a priority in the next phase of
regulatory development.
Overall the stakeholder group represents the plastics coaters, coatings manufacturers, and
State and local regulatory agencies. Some participants represent their own businesses, while
others represent trade associations or small business concerns.
2.3.2 Stakeholder Meetings
Three general stakeholder meetings were held during the initial phase of data collection
(April 1997 to July 1998). The meeting summaries are presented in appendix C. The objectives
of the initial meeting were to obtain stakeholder evaluation of EPA's preliminary data collection
efforts and industry sector characterization, receive recommendations for filling in data gaps, and
introduce EPA's options for industry-wide questionnaires. During the meeting, the major topics
discussed were:
The difficulty in characterizing the miscellaneous plastic parts sector;
The need to coordinate development of the nine surface coating MACT standards,
particularly where there is potential overlap in applicability;
Title V permit applications as a source of relevant data;
The importance of considering individual coatings as part of a coating system (as
the lowest emitting primer, colorcoat, and clearcoat cannot necessarily be used
together); and
Difficulties in reporting accurate VOC and HAP contents in coatings. The
Material Safety Data Sheets (MSDS) often list contents as a range of percentage
by weight or volume, or list minor constituents as "less than" some de minimis
value.
The second and third meetings were conducted jointly for the plastic parts and
miscellaneous metal parts surface coating stakeholder groups. There was an interest by many
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participants in both projects because of several overlapping issues (including scope and definition
of categories, plans for data collection, common application and control technologies, and overlap
with other rules and programs). In addition to discussing overlapping matters, general data
collection issues and concerns about subcategorization were also brought forward. Additional
topics included the following:
Establishing a MACT floor and types of information utilized;
Inclusion of adhesives as coatings in the regulatory development process;
Consideration of the use of low volumes of specialty coatings with high VOC
and/or HAP content;
The need for data collection via a coatings system approach (considering all
coatings applied to a particular part as a "system," thereby, addressing coating
compatibility issues);
Development of an industry-wide questionnaire, the types of information to be
collected, and the need to facilitate cooperation between all surface coating MACT
source categories; and
The possible development of a coating suppliers questionnaire to provide
additional, coating specific information not fully captured in the coating users
questionnaire.
2.3.3 Stakeholder Subgroups
Two stakeholder subgroups were formed: a regulatory stakeholder subgroup and a small
business stakeholder subgroup. These subgroups were convened to better address their specific
issues.
The small business subgroup was comprised of individuals who represented small
businesses. Some of the members of this group represented Federal and State government small
business advocacy agencies, while other members of this group represented small businesses in
the industry. The EPA's goal was to have this group provide insights from a small business
perspective as EPA moves into rule development.
The EPA conducted two conference calls, one with each subgroup. The meeting minutes
from these conference calls are included as appendix D. Lists of the participants in each subgroup
are included in the meeting notes.
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3.0 DESCRIPTION OF I II I SURFACE COATING OF
PLASTIC PARTS SOURCE CATEGORY
Surface coating of different types of plastic parts and products occurs as part of a wide
variety of manufacturing processes. The parts that are coated range in size from small plastic
logo labels on business machines to roofs and panels for heavy duty trucks. Products range from
automotive body parts to laboratory equipment, food service equipment, toys, sporting goods,
building trim materials, and computers. Most plastic products currently manufactured have
molded-in color and therefore have little or no need for coatings to be applied. Products that
receive surface coating are those that require protection from the environment in which they are
used, or for which consumers expect a certain finished appearance. In addition, operations such
as the application of adhesives, sealants, and caulks to plastic parts is considered a surface coating
operation. The major plastics manufacturing industry sectors that apply surface coatings are:
Heavy duty truck parts,
Automobile and light duty truck parts,
Business machine parts, and
Miscellaneous parts.
The SIC Codes for industries included in this source category are discussed in
section 2.2.2 and are shown in Table 2-1. There are at least a dozen four-digit SIC Codes that
include surface coating operations for plastics, but each of theses SIC Codes includes operations
and activities outside the scope of this source category as well.
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3.1 INDUSTRY PROFILE
3.1.1 Overview of the Plastic Parts Coating Industry
Plastic products are manufactured in almost every conceivable size and shape with a
variety of properties to facilitate an assortment of end uses. The coating and decorating of plastic
parts is a high priority in the plastics industry because competition to sell such varied products is
quite high.2 Selection of a decorating technique can often determine the success of a product and
can significantly affect its final market price, as finishing operations can amount to a large portion
of the total production cost. Consumer products such as automobiles, appliances, furniture,
building products, containers, and packaging usually depend on attractive decorating and
appearance for "point-of-purchase" sales.3
Plastic parts may be coated to provide color, texture, or protection, thus improving
appearance and durability. Coatings also function to attenuate electromagnetic interference/radio
frequency interference (EMI/RFI) signals and to conceal mold lines and flaws in the substrate
surface of molded plastics. Adhesives are also used for affixing predecorated materials to plastic
surfaces, and adhesive bonding of pieces is widely performed in plastics assembly processes. Such
coating and assembly of parts in the plastics industry are often referred to as "secondary
operations." These secondary operations are carried out not only by fabricators of plastic parts,
but also in product assembly facilities and contract coating facilities. Thus, the use of decorating
technology is widespread throughout the plastics industry, more so than the fabrication of plastic
parts by molding or other techniques.2
Applying a color coat is probably the most common way of decorating plastic parts for
several aesthetic, commercial, and functional reasons (for example, reflective properties). Often
the commercial failure of a plastic product can be traced to the failure of the manufacturer to
satisfy the color demands of the consumer. In today's market, color can make the difference
between selling and not selling a product.2 But whether to mold-in the color or to paint a
nonpigmented plastic product, or both, is a decision that needs to be made for each individual
case and is governed by cost, appearance quality, and product performance properties.
Plastic parts surface coating facilities may fall into three general categories: (1) an
"in-house" process located at the end-product manufacturing site, (2) a contractor shop that
specializes in plastic parts molding and coating, or (3) a contract coating facility that performs
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only painting ("toll coaters"). The complete in-house processes are common in the automotive
and truck manufacturing industries, and some business machine manufacturing sites. Such
companies will manufacture their proprietary products in-house beginning with fabrication of the
plastic pieces through finishing and assembly. Companies known as contract facilities perform
plastic parts design, molding, coating, and assembly all under one roof, but the work is contracted
by other businesses who ultimately put the end product on the market. Both types of facilities
may have conveyor finishing lines which directly transport the plastic parts through spray painting
and drying lines to the decorating and assembly areas.
Both end-product plastics manufacturing facilities and contract facilities may also ship
their plastics off-site to be finished by contract coating facilities that perform only secondary
operations. Toll coaters (contract coating facilities) may paint various types of substrates,
including plastics and metals, and can often handle both high and low volumes, some through the
use of robotic lines. The use of robots to apply coatings yields benefits which include precise
part-to-part repeatability and cost-effective high volume production and flexibility.3 Many of
these coaters serve the miscellaneous plastic parts coating sector as well. By specializing in
finishing operations (coating and/or decorating), many are able to offer a wide variety of finishes,
plating techniques, and coating processes. As such, they become specialists in applying protective
and decorative coatings and can keep up with the latest technologies, which may not be affordable
in-house at plastics manufacturing sites. Such coaters can often operate a full range of machinery
and can then accommodate all types of products. Because these facilities do not manufacture the
plastics, the parts will be coated according to the plastics manufacturers' specifications, packaged
to provide protection during transport, and returned usually with quick turn around times. Plastic
parts manufacturers consequently may find it more economical and efficient to send their parts
off-site to be coated.
Regardless of who actually performs the coating and assembly, the characteristics of the
paint or finish (i.e., color, gloss, adhesion, and chemical resistance) and the affixing of labels or
decorations are usually specified by the plastic part's end user. In some cases the end user may be
a manufacturing plant (for example, of automobiles, heavy duty trucks, business machines, or
appliances) that will be assembling the coated plastic parts to make a larger finished product, or
the end user may be the consumer, as will be the case for many miscellaneous plastic parts, such
as flower pots, shower heads, or costume jewelry.
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3.1.2 Industry Sector Descriptions
The plastic parts surface coating industry is diverse and complex. For purposes of data
collection, EPA has divided the industry into four general sectors: (1) heavy duty truck parts,
(2) automobile and light duty trucks parts, (3) business machine parts, and (4) miscellaneous
parts.
Heavy Duty Truck Parts. The heavy duty truck parts sector includes coating of both
interior and exterior components and accessories, such as grilles, chassis parts, and headlamps,
that are coated in-house within the truck assembly process line. Topcoats are applied to plastic
parts at the assembly plant, while some parts are primed off-site. Appearance and substrate
protection are often the major reasons for coating plastic parts in the heavy duty trucks
manufacturing sector.
There are 15 heavy duty truck assembly plants located in 11 States, in addition to
numerous parts plants. Virtually all heavy duty trucks are custom designed and each truck
manufacturer draws from only one coating supplier. Over the past several years, most heavy duty
truck coatings have been reformulated to a higher solids content in an effort by the industry as a
whole to lower VOC emissions. Apparently, few waterborne coatings are currently used in this
sector. Coating performance requirements for heavy duty trucks include a one million mile
warranty.4 Other coating issues identified for this industry include:
Use of customer specified colors and a large color selection (an average of 600-
900 colors are used per year in a typical plant),
Large surface areas with variable sizes and shapes,
Exposure to extreme environmental conditions,
Use of multiple substrates and primers,
Batch-type operations and mixing machines,
Low-bake requirements for touch-ups; and
Military and government coating specifications.
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As plastic components may be attached to the chassis or to other truck parts at several
points during the assembly process, plastic and metal surfaces will often be coated simultaneously,
with the same paint system.2'4 Both the curing temperature and the stiffness of the substrates
differ for metal and plastic. Coatings designed for plastics are normally quite flexible, whereas
paints for metal parts are often too inflexible for plastics. One solution is to utilize a "uni-coat
paint system" designed for products assembled from both metal and plastics that optimizes the
performance on both types of parts and allows the paint film to dry at low enough temperatures to
avoid thermal issues with the plastics.2 The use of one system that can be applied simultaneously
to metal and plastic surfaces avoids subtle color mismatches that can occur if plastic and metal
parts are painted separately.
Automohile and Light Duty Truck Parts. The automobile and light duty truck parts
sector includes coating accessories and components (both interior and exterior) for cars, trucks,
vans, and sport utility vehicles. This industry is an important consumer of molded plastics, many
of which are painted or metallized (for example, chrome-plated) such as grilles, headlamp bezels,
and wheel covers.
This sector differs from the heavy duty truck parts sector in that it does not include those
plastic parts which are coated in the automobile assembly process line because parts coated on the
assembly line are covered under the Automobile and Light Duty Truck NESHAP. However, in
this sector of plastic parts surface coating, plastic parts are often painted off-line or off-site by a
contractor who may or may not also mold the parts.
The EPA has identified 54 facilities in 11 States that coat plastic parts associated with the
automobile and light duty truck industry. Typically, over twenty different plastics types are used
in automobiles, each of which requires development and control of specific paint systems tailored
for that particular substrate and application.3 In addition, the raw materials used in the
manufacture of automotive components is a highly technical and quickly changing industry in
itself. Thus, the coatings for plastic automotive components must vary to match. Further, each
model year brings additional automotive components that are formed from plastic compounds.
Plastic is replacing metal, or in the case of lighting assemblies, glass, to meet the demand for
weight and cost reduction, greater durability, and recyclability. The plastic components require
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functional and decorative coatings that meet the same demands as the metal or glass parts that
they replace.3'5
Business Machine Parts
The business machine parts sector includes coating of plastic housings for electronic office
equipment such as computers, photocopy machines, typewriters, word processors, telephones,
and medical equipment. The plastic components in this industry sector are coated for three major
reasons: (1) to improve their appearance, (2) to protect the plastic part from physical and
chemical stress, and (3) to attenuate EMI/RFI signals that would otherwise pass through the
plastic housing.1 The coating of plastic components for the business environment is primarily
driven by appearance and functionality. For example, structural foam is widely used for electronic
equipment housing and similar applications. The surface of such rigid plastic foams often exhibits
swirl and other imperfections which requires extensive finishing, including priming and painting.5
Some of the business machines manufactured are used in outdoor or laboratory conditions. These
machines must be able to withstand the physical and chemical stresses of their operating
environment. Additionally, business machine components require EMI/RFI coatings critical to
their proper functioning. EMI/RFI signals emitted from enclosed electronic components can pass
through plastic housings. These signals, when emitted from business machines, may interfere with
the performance of other electronic devices such as radios and televisions. Conversely, EMI/RFI
signals from outside sources can also hinder the proper functioning of electronic components in an
unshielded plastic business machine. To combat EMI/RFI propagation, the FCC has placed
restrictions on the maximum EMI/RFI emissions from computing devices. Coatings are
frequently used to comply with these restrictions. Copper, nickel, silver, or other metallic-
impregnated paints are applied to plastic surfaces that require such shielding. Application of an
additional, conformal coating (an insulative barrier) must often be applied over the EMI/RFI
shielding.6
The EPA has identified 50 facilities in 22 States that coat plastic parts associated with the
business machine industry. There are also companies that specialize in the refinishing of plastics
(for example, the plastic covers of certain types of office equipment and business machines).
Additionally, metal and plastic pieces will frequently be coated together, especially when larger
machines, such as photocopiers, are recoated.7 Recoating the external panels of office equipment
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can restore their original appearance or change their color and reduces the amount of plastics sent
to landfills.
Miscellaneous Parts. The miscellaneous part sector covers numerous products in a
variety of industries. Miscellaneous plastic parts may be found in appliance products (for
example, clothes washer and dryer components, hair dryer components, stereo sets, television and
radio housings), plumbing and marine products (for example, shower heads, faucet handles,
housings for boat lighting fixtures), household products (for example, flower pots, frames for
pictures and mirrors, lighting fixture bases), and other consumer products (for example, cosmetic
cases, trophies, toy components, costume jewelry, sporting goods, optical lenses for safety glasses
and goggles). While many miscellaneous plastic parts are made from plastics with molded-in
color, surface coatings are applied to a wide variety of these parts.
The EPA has identified 396 facilities in 33 States that coat plastic parts associated with the
miscellaneous plastic parts industry. The coating selections and requirements for the
miscellaneous sector depend on the end use specifications. However, as discussed previously,
appearance and protection will tend to be important considerations. Some of the major reasons
for coating might include the need for highlighting, texturing, protection, appearance uniformity,
hiding defects, functionality, or creating a second surface (unique to transparent plastic parts).8 In
some cases, metal and plastic parts are assembled and coated simultaneously.
Toll coaters comprise a large portion of the miscellaneous plastic parts coating sector.
These companies often specialize in the coating, decorating, and assembling (including the
application of adhesives, sealants, and caulks) of various parts with differing sizes and shapes.
Thus, they are an obvious choice for manufacturers of miscellaneous plastics who require these
secondary operations.
3.2 COATING PROCESS DESCRIPTION
This section of the document describes the operations typically conducted at facilities
coating plastic parts. The primary basis for this description is the site visits discussed in
section 2.2.2 and the plastic parts ACT document.1 Considerable variability exists among the
plastic parts surface coating facilities, so the focus of this section is not on a typical coating line
operation but rather on the individual processes that can comprise a coating line. At any given
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facility, the number and sequence of operations will be a function of the plastic substrate being
coated and of the given coating. But some general principles are common to all plastic parts
surface coatings, and these are discussed below.
Section 3.2.1 describes the processes typically found on a coating line. Section 3.2.2
mentions some of the differences found at a smaller contract coating facility. Section 3.2.3 details
common application techniques for coating and Section 3.2.4 provides some general information
about ancillary processes (including adhesives application).
3.2.1 Typical Surface Coating Processes
Because of the wide variety of plastic parts and coatings, no generic coating line
description can adequately convey the range of operations at surface coating facilities. Coating
lines vary not only in composition (for example, different numbers of coating stages and drying
ovens) but also in degree of automation. Some coating lines are incorporated together such that
plastic parts are conveyed through the coating sequences mechanically, while other coating lines
consist entirely of manual operations. This section of the document will therefore discuss the
common stages typically encountered in a coating line rather than describing a specific
configuration that is typical to the industry.
Surface Preparation. Surface preparation is performed for two main reasons, to correct
any flaws in the part prior to coating and to prepare the part to receive the coating. Some sanding
may be performed to remove burrs or other surface inconsistencies. Puttying may be necessary to
fill in any gaps or small cracks in the plastic part. For pre-primed plastic parts, spot primer may
be applied to any areas missing primer or with an inconsistent primer application. Following this
type of pretreatment, any remaining surface residue must be removed, typically by wiping off the
dust with water or solvent-soaked rags. Acetone or a hot water and grit material solution can
also be used as an alternative to HAP or VOC-laden solvents to remove any tape adhesion, dirt,
or dust.
Varying degrees of cleaning are possible, including multiple washing cycles with
proprietary soaps or solvents or deionized water. Also, depending on the types of coating to be
applied, surface preparation can include treatment of the part to provide for better coating
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adhesion. For example, applying a conductive coating is necessary for plastic parts to be coated
by some electrostatic coating application techniques.
Spray Booths. Coatings are typically applied in partially or totally enclosed spray booths.
(Spray application techniques are further discussed in section 3.2.3.) The degree of automation of
the coating line is usually a function of the size of the facility and the range of types of plastic
parts coated. Automated spray booth systems are more likely to be used in larger facilities or for
parts with flat or uniform surfaces. Parts may be manually wheeled to the spray booths on drying
racks and placed into and out of the booth by hand, or the parts may be automatically conveyed to
the booths via racks or paint hooks.
Regardless of how the parts are introduced into the spray booth, the booths have some
common characteristics. A positive or negative pressure exhaust system is used to ensure airflow
though a filtering mechanism. Some typical configurations include down draft airflow through a
water curtain that runs below a grilled floor, and cross draft airflow through dry filters on the rear
wall of the booth. The exhaust system reduces the airborne solvent concentrations to safe levels
inside the booths and these filtering mechanisms control overspray. Overspray is the coating
solids that either miss or bounce off the part (see discussion of transfer efficiency in section 3.2.3).
Partially open booths are subject to the ambient environmental conditions at the facility,
but fully enclosed booths are typically monitored to ensure a desired exhaust airflow, temperature,
and humidity (all of which contribute to the quality of the finished part's coating). A coating line
can consist of a combination of booth types, and a single part may be coated multiple times in the
same booth to apply different coatings with different properties (such as color).
Tape, paper, or other type of shield can be used to mask certain portions of the plastic part
so that the color is applied only to the proper area. The part is coated in one color, masked, and
then coated in a different color. When the masking is removed, the part will have the multiple
colors in the designated areas.
When a coating is changed in a paint booth, the spray equipment must be cleaned prior to
introduction of the new coating. This is usually accomplished by running an amount of cleaning
solvent through the spray equipment in the booth. The degree of cleaning necessary and the types
of solvents used are both functions of the previous coating and the next coating. The booth itself
is cleaned regularly (once a week is typical) with solvent or water-based cleaning solutions.
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Operators clean some booths by spraying a special coating onto the interior surface of the booth
itself. This coating easily peels off, capturing any dust or overspray that was previously on the
booth's walls.
Captured overspray must be disposed. In a wet booth, where overspray is controlled
through a water curtain, the water must be treated to remove the suspended coating solids. In dry
booths, the filters are routinely replaced. Spent filters are typically disposed of as hazardous
waste.
Flash-off Zones. Immediately following coating application, plastic parts are introduced
into a flash-off zone. This zone can be a designated area on an automated coating line between
the spray booth and curing oven, or the zone can simply be the drying rack in a manual line where
the parts are placed prior to entering a curing oven. The purpose of the flash off area is to allow
partial curing as solvent evaporates from the coated part.
Curing Ovens. Conventional coatings for plastics are generally classified as high-bake or
low-bake. High-bake coatings require elevated temperatures to fully cure. Typical temperature
and residence time for high-bake coatings is 20 minutes at up to 300 °F, whereas typical
temperature and residence time for low-bake coatings is 20 to 30 minutes at up to 130 °F. Many
plastic part coatings will cure satisfactorily at ambient conditions, but plastic parts are often
introduced to elevated temperature to speed the curing time.
The desired curing conditions, including temperature, residence time, and humidity, are
highly dependent on the type of coating used and the properties of the substrate being coated.
For example, a coating that requires a bake temperature of 300 °F cannot be used on plastic that
deforms or distorts at that temperature. Therefore, substrates such as acrylonitrile butadiene
styrene resins and epoxies that are not heat tolerant require coatings that cure at low
temperatures. Such coatings tend to have higher VOC or HAP content to promote adequate
curing speed.
Other coatings, such as ultraviolet (UV) curable coatings, will require special curing
stages. For example, a UV curable coating cures under UV lamps.
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3.2.2 Contract Coaters
Many smaller, contract coating facilities coat a variety of miscellaneous plastic parts.
These facilities apply coatings that are supplied or otherwise specified by their clients. Their
operations must therefore be flexible enough to incorporate a wide range of coatings and
application technologies, and substrate types.
Because of the variability inherent to such operations, dedicated coating lines are not
typically found in the industry. Instead, several coating booths may be stationed throughout the
facility, and parts can be manually moved on racks from manufacturing areas to surface
preparation to coating. Parts can then flash-off and cure at room temperature or in drying ovens
that are not necessarily dedicated to spray booths in a conventional coating line structure. The
operations that are performed are a function of the plastic part being coated and the coating being
applied, and therefore not every part will go through every process. For these facilities,
operational flexibility is a key component to their business.
3.2.3 Application Technologies
The majority of coating applications is achieved through spray technologies. Adhesives,
sealants, and caulks, however, may be hand-applied through a variety of methods. This section
focuses on spray application techniques.
As briefly discussed in section 3.2.1 (spray booths), overspray is the amount of coating
solids that either miss or bounce off the part being coated. Transfer efficiency is defined as the
ratio of solids adhering to solids sprayed. Numerous factors affect how well a coating is
transferred to a part, including the type of spray equipment, the part shape, the spray booth
characteristics and the operator's skill. The various spray techniques used to coat plastic parts
differ in the manner in which they break up, or atomize, the coating. Some methods have better
transfer efficiencies for a specific substrate and a given coating. Common methods include:
Conventional Air Spray. Conventional air spray is the traditional method of
applying coatings. Compressed air is supplied through an air hose to a spray gun,
which atomizes the coating into a fine spray. The pressure supplied to the fluid
controls the coating delivery rate, with typical pressures ranging from 5 to
25 pounds per square inch (psi). The air pressure controls the degree of
atomization, and is usually 30 to 90 psi. One of the major problems with
conventional air spray is the overspray caused by the high volume of air required
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to achieve atomization. This overspray typically results in a relatively poor
transfer efficiency.
Airless Spray. With airless spray, a pump forces the coating through an atomizing
nozzle at high pressure (1,000 to 6,000 psi). Airless spray is ideal for rapid
coverage of large areas and when a heavy film build is required. The size of airless
spray paint droplets is larger, the spray cloud is less turbulent, and the transfer
efficiency is typically superior to conventional air spray. However, airless spray
leaves a rougher, more textured surface; therefore, it is generally used on surfaces
where appearance is not critical.
Air-Assisted Airless Spray. An air-assisted airless system combines the benefits of
conventional air spray and airless spray. The system consists of an airless spray
gun with a compressed air jet at the gun tip to atomize the coating. It uses lower
fluid pressures than airless spray and lower air pressures than conventional air
spray (5 to 20 psi versus 30 to 90 psi). This combination of fluid pressure and air
pressure delivers a less turbulent spray than conventional air systems and applies a
more uniform finish than airless systems. However, the amount of time needed to
apply coatings is greater because of the lower air pressure.
High-Volume/Low-Pressure fHVLP) Spray. A modification of conventional air
spray is HVLP spray, which uses large volumes of air under reduced pressure (10
or less psi) to atomize coatings. Because of the lower air pressure, the atomized
spray is released from the gun at a lower velocity. Overspray is reportedly reduced
25 to 50 percent over conventional air spray. The air source for the HVLP can be
a turbine or a standard air supply, both of which can handle multiple spray guns.
Manufacturers have constructed the fluid passages out of stainless steel or plastic
so that these guns are compatible with a full range of paints, solvents, and water
based materials. Many HVLP spray systems are designed to atomize high-,
medium-, or low-solids coatings.
Electrostatic Spray. In electrostatic spray application, the coating and part are
oppositely charged. The part is grounded and attracts the negatively charged
coating. Electrostatic spray systems are reported to have the highest transfer
efficiency of any of the spray application techniques because of minimal overspray,
which also results in lower paint loss and lower VOC emissions. One limitation of
the electrostatic spray technique is that the part to be coated must be conductive.
Plastic parts not made of a conductive substrate are often made conductive by
applying compatible polar solutions to the surfaces and/or placing the parts on a
metal backing.
Zinc-Arc Spray. Metallic zinc may be applied to plastic to provide a conductive
surface or shielding. This two-step process first roughens the plastic surface
(usually the interior of a housing) by grit-blasting or sanding, and then spray-coats
with molten zinc, either manually or with robotics. The zinc-arc spray gun
operates by mechanically feeding two zinc wires into the tip of the spray gun
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where they are melted by an electric arc. A high-pressure air nozzle blows the
molten zinc particles onto the surface of the plastic part.
3.2.4 Ancillary Operations
Plastic parts coating facilities generally include additional operations that have the
potential to introduce VOC or HAP into the atmosphere. In particular, equipment cleaning and
adhesives application have been included in the data gathering tasks. In addition, many facilities
(especially those with automated coating lines) will have an inspection or finishing area where
touch-up coatings are applied to complete the final product. These activities will be assessed as
part of the plastic parts surface coating source category because they are potential sources of
VOC and HAP emissions at the facilities coating plastic parts.
Equipment Cleaning. As previously discussed in section 3.2.1 (spray booths), when a
change in coating is made the spray equipmentand perhaps the booth itselfmust be cleaned.
Cleaning solvents are typically used to spray through the application equipment or wipe down the
interior of the spray booth. Acetone, toluene, or xylene can be used to clean spray guns and
purge the coating lines of solvent-based coatings. Water-based coatings can be cleaned from the
equipment with water. The interior of the spray booths can be cleaned with solvent, water, or a
water-based peel-off cleaner that is sprayed on the interior walls directly.
Cleaning solvents may be used in the touch-up areas to either prepare a part for a
touch-up coating or to clean a part prior to final product delivery. For example, MEK can be
wiped by hand across the plastic part to make it appear clean and shiny prior to shipment.
Spent cleaning solvents are collected along with coating waste. These materials are
typically treated or disposed off-site although some facilities collect spent solvents and recycle and
reuse them on-site.
Adhesives Application. Some facilities manufacture and assemble the plastic parts that
they coat, and this often involves glueing two pieces of plastic together. While some advanced
adhesive-free technologies, such as ultrasound welding, are applicable to certain limited
applications, most adhesion is accomplished through application of a solvent or combination of
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solvents. Typical adhesives include tetrahydrofuran, methylene chloride, and methylphthalate-
based two-part epoxies.
The solvent breaks down the plastic molecules on the surfaces to be joined, and the fused
part, following adhesion, has strong bond characteristics. Because of the interaction between the
solvent adhesive and the plastic substrates, not all adhesives will perform with all substrates.
Substrate properties and desired bond strength dictate which adhesives can be used.
Solvents used for adhesion are often stored in air-tight canisters and are applied to the
plastic through syringes or other methods that minimize the possibility of VOC or HAP emissions
by minimizing the amount of solvent used and the exposure time of the solvent to the air. Some
volatilization will occur as the adhesive cures.
Touch-up. Coatings are often applied in a touch-up area to repair slight imperfections or
to fill in areas that were not completely coated during the process. These coatings can be
spray-applied in a booth, but they are often applied via other means such as brush application or
aerosol cans. The coatings in the touch-up area, because they do not receive the same degree of
carefully controlled curing times and temperatures as the main coating, have different
characteristics. Touch-up coatings are typically solventborne and have higher VOC content than
the standard coatings in use at a facility.
3.3 EMISSIONS CHARACTERIZATION AND CONTROL
The primary sources of information used to characterize emissions and controls are the
plastic parts ACT document and site visits conducted by EPA.1 To update this information,
emissions characterization and control options will be a major focus of future data gathering
efforts. Section 3.3.1 describes the sources and composition of VOC and HAP emissions from
plastic parts surface coating. Section 3.3.2 details various control technologies.
3.3.1 Emissions Characterization
Emissions of VOC and HAP at surface coating facilities primarily occur at the surface
coating operation itself. Most VOC and HAP emissions occur at the spray booth, in the flash-off
zone, or in the drying ovens, while some potentially significant emissions may occur at ancillary
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operations such as surface preparation, plastic part adhesives application, equipment clean-up,
coating storage and mixing, or plastic parts touch-up.
Emission Points. Emission points occur at all three main areas of the coating line (spray
booths, flash-off zones, and curing ovens) discussed in section 3.2 of this document. The percent
of total emissions attributed to each is a function of several factors, including the transfer
efficiency in the spray booth, the length of time spent in flash-off, the use of curing ovens, and the
characteristics of the substrate and coating. Where emissions are occurring and how much are
attributable to each area may limit the control options. For example, the spray booths and drying
ovens may be enclosed and routed to a control device while a flash-off zone is typically open to
the facility interior (and therefore indirectly emitted to the atmosphere).
Transfer efficiency has a significant affect on the distribution of emissions. Only the
coating that actually impacts and adheres to the plastic part will leave the booth with the part and
will have an opportunity to dry (i.e., the solvent evaporates) outside of the spray booth. For
example, if the transfer efficiency is 30 percent, then at least 70 percent of the overall emissions
occur at the spray booth. Additional emissions from drying are presumed to occur in the spray
booth after the part is coated, but before the part can be removed from the booth to a flash-off
zone or to a drying oven. For example, if several similar parts are being coated in a spray booth
at the same time, the first parts coated will begin to dry as the rest of the parts are coated. The
majority of these emissions from the booth depend in part on the amount of time the parts remain
in the booth.
Emissions from the flash-off zone are a function of the amount of time spent in the zone,
the humidity in the zone, and the characteristics of the substrate-coating combination. Some
coatings applied to plastic substrates have a low drying temperature (i.e., they contain solvents
with a low boiling point). Significant drying of these coatings can occur in the flash-off zone,
resulting in greater emissions during flash-off and a relatively small portion of the total emissions
from the subsequent drying oven. Emissions from flash-off zones are not typically controlled, and
they may account for a significant portion of the HAP and VOC emitted during the coating
process.
Drying ovens, if present, produce additional emissions in a closed system as the coating
continues to dry. But, as previously discussed, much of the solvent present in the coating may
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have already evaporated prior to the drying oven. A high-bake coating, however, may not
significantly dry in the flash-off zone, so emissions in the drying oven are expected to be greater
than in the flash-off zone.
The properties of the coating itself, especially the curing time and temperature required,
influence where in the process the emissions result. Quicker cure times, for example, can cause
greater emissions in the spray booth and flash-off zones before the coated part is transferred to
the curing oven.
Some additional emissions are also possible as chemical reactions continue in the coating
for some time, perhaps even beyond the drying oven. These emissions are referred to as "cure
volatiles" because the chemicals emitted may not be present in the coating or the substrate prior to
curing of the coating. Most of the total emissions, however, can be assigned to the spray booth,
flash-off zone, or curing oven.
The configuration of these operations can influence the emissions as well. For example, a
facility where plastic parts are manually moved from a rack into a partially enclosed spray booth
under a vented hood will have different emission characteristics than an automated facility with a
totally enclosed spray booth. Plastic parts coated one by one in a partially enclosed booth will
produce emissions during flash-off from the drying rack after they are coated and as the rest of the
parts are coated. These emissions will occur outside the booth. In a fully enclosed booth, flash-
off will occur mainly in the spray booth as the rest of the parts are coated.
Work practices can also affect the amount and distribution of HAP and VOC emissions.
Coating supplied to the spray booth can be accomplished by fully enclosed piping from the mix
room to the booth or by hand-carried buckets. Mixing can be performed manually or
automatically in different methods that expose the coating to the atmosphere for different times.
In addition, the quantity of coating mixed can affect emissions (for example, 5 gallon buckets have
a larger surface area for evaporation than pint-sized containers). In general, manual, open work
practices provide a greater opportunity for HAP and VOC emissions than enclosed or automated
work practices.
Additional emission points may be associated with surface preparation, adhesives
application, part cleaning, and touch-up. The potential for emissions also exists where the
coatings are stored and during mixing and transfer to the spray booths. Also, some air emissions
may result from solvent distillation if a facility reclaims its own cleaning solvent on-site.
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HAP and VOC Emitted. The compounds emitted from plastic part surface coating are the
volatile components of the coatings. The EPA assumes that 100 percent of the solvent in the
coating, including any solvents or thinners added to the coating at the facility, is emitted.
Therefore, a mass balance of VOC and volatile HAP can be used to estimate emissions if coating
VOC and HAP content and coating usage data are known. The mass balance should also attempt
to estimate the type and quantity of cure volatile emissions because the cure volatile species
formed and emitted may not be present in the coatings (i.e., the "inputs" to the mass balance)
prior to curing.
Estimates of total VOC emissions are usually obtainable as the coaters have data on the
solids content, water content, and solvent content of the coatings applied. Coupled with data
identifying the quantity of the coatings applied, a mass balance for total VOC can be calculated.
Individual VOC and HAP species emitted, as well as total HAP emissions, are less easily
obtained, as the precise coating content information is typically proprietary. MSDS are required
to list only those VOC and HAP species that comprise greater than 1.0 percent by weight
(0.1 percent by weight for carcinogens). All contents can be reported on an MSDS as a range or
maximum volume percentage of the components. Even full-disclosure MSDS, which may present
every component of the coating, typically report ranges for the percentages.
Some HAP species have been identified as common components of coatings used for
plastic parts, including the following:
Ethyl benzene,
Ethylene glycol,
Formaldehyde,
Glycol ethers,
Methanol,
Methyl ethyl ketone,
Methyl isobutyl ketone,
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Toluene, and
Xylene.
All of these HAP are also VOC. Some coating components may be HAP compounds but
are not VOC. One such compound is nickel, which is used for EMI/RFI shielding. Furthermore,
it is likely that many VOC components in coatings are not listed HAP.
3.3.2 Control Technologies
Several different control strategies are applicable to the plastic parts surface coating
industry. In general, control technologies consist of either pollution prevention practices, process
modifications, or add-on control equipment. This section briefly describes the types of controls
EPA encountered during site visits. In addition, it includes a summary of the plastic parts ACT
discussion of control techniques.1
Control Technologies from the Site Visits. The most common control technique EPA
encountered during the initial site visits was HVLP spray equipment used inside a fully or partially
enclosed spray booth, with the booth exhaust routed through a water wash system or dry filter.
As discussed in section 3.2.3, HVLP equipment can reduce overspray, lowering coating
consumption as well as emissions.
Fully enclosed spray booths can be vented through a water wash or dry filters, with the
primary function being control of particulate matter emissions. Wastewater from a water wash
must be treated either on- or off-site. On-site treatment may include separation and removal of
the captured coating solids. Dry filters and recovered coating solids are generally discarded as
hazardous waste following use.
Many facilities and suppliers have attempted to find suitable low VOC content coatings,
especially over the previous 5 to 10 years. While some have been adopted, the nature of some
plastic substrates, combined with desired finish characteristics, currently appear to require high
VOC content coatings.
Another common approach that State agencies use to limit emissions is through permitting
a facility to operate with some degree of averaging. A facility can operate under a facility-wide
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average VOC content limit (for example, a facility-wide 3.5 pounds/gallon VOC coating content
limit, based on a monthly average). Such a limit is flexible enough to permit small amounts of
high VOC content coatings to be used so long as most of the coatings have a low VOC content.
Control Technologies Discussed in the ACT Document. The plastic parts surface
coating ACT provides detailed information (current in 1994) regarding several control
technologies, including many pollution prevention measures.1 Waterborne and high solids
content coatings are discussed as are two low VOC content coatings. In addition, the ACT
details non-emitting technologies including UV curing, powder coatings, and vapor cure coatings.
The ACT explains each of these pollution prevention measures, provides the merits of each, and
discusses the suitability of each to surface coating of plastics parts.
The ACT contains information on process modifications such as switching the spray
equipment to HVLP spray guns. Much of this information is presented in terms of potential
environmental benefit, but EPA recognizes that many facilities may have already modified their
processes to take advantage of HVLP technology.
In addition, the ACT provides detailed discussions of the following control devices:
incinerators, carbon adsorbers, incinerators coupled with carbon adsorbers, absorbers
(i.e., scrubbers), and condensers. The ACT provides the suitability, typical control efficiencies,
and other characteristics of each control device.
3.4 SOURCE CATEGORY SCOPE AND OVERLAP
The EPA identified several issues relating to the scope of and overlap with the plastic
parts surface coating source category. Section 3.4.1 discusses the scope of the plastic parts
surface coating source category. Section 3.4.2 addresses overlap among the surface coating
source categories for which rules are currently under development. Section 3.4.3 summarizes
existing Federal and State regulations that have the potential to overlap with the plastic parts
surface coating source category.
3.4.1 Scope
For purposes of regulatory development, the scope of the plastic parts surface coating
source category will include not only the processes that apply coatings (i.e., traditional coatings,
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adhesives, sealants, and caulks) to plastic parts but also the ancillary operations necessary to the
coating application. These ancillary operations include surface preparation, coating storage and
mixing, and equipment clean-up.
Including particular processes in data gathering activities does not necessarily imply that a
MACT floor or standards will be set for all of those processes. The EPA collects information
regarding these processes, particularly regarding HAP and VOC emissions, and then assesses the
findings to determine if they are significant emission sources and their potential for control.
Information collection could reveal that certain parts of a process do not, in fact, contribute
significantly to HAP or VOC emissions. In such a case, EPA could decide not to set standards
for that particular part of the process. Data collection on the surface coating of plastic parts
source category is still ongoing. At this time, a decision has not been made as to which emission
sources will be covered by standards.
In addition, statutory language regarding the regulated entity affects the definition of the
scope of the source category. For MACT standards under section 112 of the Act, the regulated
entity is the source of emissions of the HAPs listed in section 112(b) of the Act; for plastic parts
coating, this is the facility where coating application takes place. Section 183(e) of the Act states
that the regulated entity for federal VOC rules is the manufacturer, processor, wholesale
distributor, or importer of the consumer or commercial product listed for regulation. For plastic
parts coating, this would be the coating manufacturer. On the other hand, if EPA makes a
determination under section 183(e)(3)(C) of the Act to regulate plastic parts coatings with a
CTG, then the regulated entity for Reasonably Available Control Technology (RACT) is the user
of the product (i.e., the coater). The EPA has not yet made a determination that a CTG would be
significantly as affective as a federal VOC rule.
3.4.2 Overlap with Other Source Categories
The list of source categories to be regulated with MACT standards under section 112 of
the Act and the list of consumer and commercial products to be regulated under section 183(e) of
the Act both include several industrial surface coating operations. Some of these categories are
related or similar to plastic parts coating, and there is a certain potential for overlapping
applicability among the planned standards for these industries. In particular, the miscellaneous
metal parts, boat manufacturing, reinforced plastic composites manufacturing, automobile and
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light duty truck assembly, large appliances, metal furniture, and miscellaneous industrial adhesives
source categories have potential overlap with the plastic parts source category. Table 3-1 lists
these source categories, the rules under development for them, and the EPA's current
recommendations regarding their potential applicability. These rules include:
Miscellaneous Metal Parts. The miscellaneous metal parts surface coating source
category includes coating of metal parts and products. In some industrial
operations such as surface coating of heavy duty truck cabs, metal and plastic parts
are often assembled and then coated simultaneously with the same coating. As
another example, the plastic and metal parts can receive different prime coats, each
of which prepares the respective substrate for the identical color coat. In order to
avoid having a single coating or coating application subject to two different
MACT or VOC standards, regulatory development for the two source categories
are being coordinated. Potential solutions might include: (1) coordinate the two
projects and develop a single MACT floor applicable to both substrates, or
(2) include coatings applied to metal and to plastic within the scope of only one of
the source categories. The regulatory development process for miscellaneous
metal parts and for plastic parts has been closely coordinated since the outset.
Joint site visits and stakeholder meetings have taken place, and data on coating
contents and coating processes have been shared where plastic and metal
substrates are both involved. For the next phase of data collection (the MACT
survey), the miscellaneous metal parts project will be collecting data on surface
coating operations where metal and plastic are coated simultaneously.
Boat Manufacturing. Coating operations are performed at some fiberglass boat
manufacturers (about one quarter to one third) and at all aluminum boat
manufacturers. The boat manufacturing NESHAP project is collecting information
on these coating operations at both fiberglass and aluminum boat manufacturers.
The EPA has not made a final decision, but is considering regulating coating
operations at all boat manufacturers (except those regulated by the shipbuilding
and repair NESHAP) under the boat manufacturing NESHAP to streamline the
applicable NESHAP. Alternatively, boat manufacturing coating operations could
be regulated under the plastic parts surface coating NESHAP or the miscellaneous
metal parts NESHAP. Boat manufacturers would include those facilities that build
hulls and decks of boats. Plastic parts facilities that only manufacture smaller boat
parts (such as seat pedestals or bait boxes), as well as other plastic parts, would
not be subject to the boat manufacturing NESHAP.
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TABLE 3-1. POTENTIAL OVERLAPPING SOURCE CATEGORIES
Source Category
Regulations
Statutory
Schedule
Scope of Regulation
Potential Overlap with Plastic Parts Surface
Coating
Surface Coating of
Miscellaneous Metal Parts
Section 183(e), BAC/CTG
Section 112, MACT
2001
2000
Coatings applied to metal parts,
including automotive and heavy
duty truck parts.
Potential overlap would occur on heavy duty truck
manufacturing lines, where many plastic and metal
parts are coated simultaneously, with identical coatings.
Fiberglass and Aluminum
Boat Manufacturing
Section 183(e), BAC/CTG
Section 112, MACT
2001
2000
Manufacturing process, including
application of coatings.
Coating of fiberglass boats is a plastic surface coating
operation.
Reinforced Plastic
Composites Manufacturing
Section 112, MACT
2000
Manufacturing processes, does not
address coating.
Coating of reinforced plastic may be covered under
plastic part surface coating.
Automobile and Light Duty
Truck Assembly Coatings
Section 183(e), BAC/CTG
Section 112, MACT
2003
2000
Coating of both metal and plastic
parts for automobiles and light duty
trucks that occurs on the assembly
line.
Potential overlap with automotive plastic parts: a
single plastic part may receive a prime coat off-site and
a topcoat on the assembly line; parts may be coated at
the assembly facility, but in off-line booths; parts coated
off-site may receive touch up on the assembly line;
coatings applied off- site must be color-matched with
on-line coatings.
Surface Coating of Large
Appliances
Section 183(e), BAC/CTG
Section 112, MACT
2003
2000
Coatings applied to any large
appliance part or product.
Some plastic parts and products at large appliance
facilities may not fall within the scope of the large
appliance rules; the plastic parts surface coating source
category would be applicable to these parts and
products.
Surface Coating of Metal
Furniture
Section 183(e), BAC/CTG
Section 112, MACT
2003
2000
Coatings applied to metal furniture
parts or products.
Plastic parts may be added to the furniture prior to
coating, or they may be coated at the same site.
Miscellaneous Industrial
Adhesives
Section 183(e), BAC/CTG
2001
Miscellaneous industrial adhesives
applied to a variety of substrates,
including plastic.
Potential overlap with adhesives applications that are
covered under plastic parts surface coating.
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Reinforced Plastic Composites Manufacturing. At this time, the reinforced plastic
composites manufacturing source category covers the manufacturing process only,
including preparation and clean-up but not including surface coating. Any surface
coating of reinforced plastic composite parts and products will be addressed under
the plastic parts NESHAP. The EPA is currently assessing the data needs for this
sector.
Automobile and Light Duty Truck Assembly Coating. Overlap between
automobile and light duty truck assembly coating and plastic parts coating might
occur for plastic automotive parts. However, the potential for a particular coating
operation to be subject to rules for both categories can be eliminated by careful,
coordinated development of the definitions of the affected facility in both rules.
The automobile and light duty truck source category is intended to cover assembly
line coating processes. The plastic parts source category is intended to cover
automotive parts coated by contract coaters, but it also incudes parts coated at an
automobile and light duty truck assembly facility if they are not coated on the
assembly line. Ensuring the compatibility of the standards for the two source
categories is also an important concern. For example, if a prime coat is applied
off-line (therefore subject to the plastic parts standards) and a color coat is then
applied to the same part on an assembly line (therefore subject to the automobile
and light duty truck standards), the standards must accommodate a primer that
compatible with the color coat. During the next phase of data collection, the
plastic parts project will be gathering data from contract coaters and automotive
part suppliers. The automobile and light duty truck assembly project will be
gathering data from automobile assembly facilities that coat plastic products off the
main assembly lines.
Large Appliances. The large appliance source category includes any facility
engaged in surface coating of any large appliance part or product, such as ranges,
ovens, dishwashers, and water heaters. It is likely that some facilities produce
plastic parts for large appliances and parts for other applications (perhaps using the
same equipment or coatings). The small plastic appliances and other plastic parts
not subject to the large appliances NESHAP will be subject to the plastic parts
NESHAP. The large appliance project is responsible for gathering data from these
facilities.
Metal Furniture. The metal furniture source category includes any facility engaged
in the surface coating of metal furniture parts or products, such as desks, tables,
bookcases, and chairs. The scope includes paint mixing, cleaning, application, and
adhesives. Some metal furniture may include plastic parts (for example, castors on
a metal chair or plugs to cover rough edges on a metal shelving unit). If coated,
these plastic parts may be attached to the metal furniture prior to coating. They
may also be coated separately before assembly. The metal furniture project is
gathering data from these facilities and will continue to coordinate with the plastic
parts project team.
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Miscellaneous Industrial Adhesives. Volatile organic compound emissions from
the application of miscellaneous industrial adhesives will be addressed under
section 183(e) of the Act. The plastic parts source category currently includes
adhesives applications for parts that are also surface coated. The EPA is still
determining if adhesives application for parts that are not coated (for example,
parts with molded-in color) will be covered if they are co-located with plastic parts
coating operations. Adhesives application to plastic parts at facilities where
coating does not occur will presumably be covered by the miscellaneous industrial
adhesives source category. At this time, EPA is collecting data at facilities coating
plastic parts and is obtaining data relevant to adhesives application at the facilities.
Because of the way the survey recipients list was developed, data may also be
collected for adhesives only facilities. Relevant data will be shared with the
miscellaneous industrial adhesives project.
3.4.3 Overlap With Existing Rules
In addition to potential overlap with other source categories to be regulated under
sections 112 and 183(e) of the Act, EPA has identified some potential overlap issues with other
regulations. For example, the Federal Aviation Administration requires certain characteristics for
interior parts of airplanes, such as chairs or wall panels. These requirements may specify that the
part be flame resistant or give off no toxic fumes when burning. While not directly regulating the
adhesives and coatings used, these requirements restrict which coatings and adhesives can be
used.
The EPA is sensitive to the potential conflict between overlapping regulations for plastic
parts, and is collecting data from coaters of plastic parts regarding any regulatory specifications
that influence the choice of coatings used. The EPA is attempting through the industry survey to
address overlap with any such programs, including: Federal Aviation Administration
requirements, Food and Drug Administration requirements, Federal Communications Commission
requirements, the requirements of the Safe Drinking Water Act, the requirements of the National
Highway and Transportation Safety Act, National Transportation and Safety Board requirements,
and Department of Defense military specifications.
In addition, some surface coating of plastic parts is currently regulated by New Source
Performance Standards (NSPS). The NSPS is described in more detail in section 3.5. In general,
the NSPS limits the amount of VOC in coatings that are applied to office equipment, laboratory
machines, and computers. The NSPS applies to coating booths constructed after January 1986.
"Business machines" is defined in the NSPS as:
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"...a device that uses electronic or mechanical methods to process
information, perform calculations, print or copy information, or
convert sound into electronic impulses for transmission."
Examples of business machines given in the NSPS include typewriters, electronic computing
devices, calculators and accounting machines, telephone and telegraph equipment, and photocopy
machines. Overlap with the business machines NSPS occurs because the plastic parts surface
coating source category encompasses the NSPS affected facilities.
In addition to the business machines NSPS, there are other existing Federal rules which
may overlap with the plastic parts and products source category. The EPA will continue to
analyze these rules throughout the regulatory development to minimize duplicative or
contradictory requirements. The rules that may overlap with plastic parts include the following:
NESHAP for Aerospace Manufacturing and Rework Facilities, 40 CFR part 63,
subpart GG;
NESHAP for Wood Furniture Manufacturing Operations, 40 CFR part 63,
subpart JJ; and
Proposed National Volatile Organic Compound Emission Standards for
Automobile Refinish Coatings, 40 CFR part 59 (62 FR 67784).
3.5 SUMMARY OF EXISTING FEDERAL AND STATE REGULATIONS
A number of existing Federal and State regulations address VOC content limits. Some
related Federal rules for HAP have already been promulgated as well (as outlined in
section 3.4.3). While some State air toxic programs may have ambient standards for certain
HAPs found in coatings, HAP emissions specifically from plastic part coating operations are not
regulated. Section 3.5.1 summarizes existing Federal rules (the business machines NSPS), and
section 3.5.2 addresses existing State rules.
3.5.1 Federal Rules (Business Machines NSPS)
The NSPS to control VOC emissions from the coating of plastic business machine parts is
found in 40 CFR part 60, subpart TTT. (The NSPS is included in appendix E of this document.)
The NSPS sets VOC content limits for prime coats (1.5 kilogram/liter), color coats
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(1.5 kilogram/liter), texture coats (2.3 kilogram/liter), and touch-up coats (2.3 kilogram/liter) in
any facility constructed after January 1986 in which plastic parts are coated for use in
manufacturing business machines. The standard defines the business machine sector as
typewriters (SIC Code 3572), electronic computing devices (SIC Code 3573), calculating and
accounting machines (SIC Code 3574), telephone and telegraph equipment (SIC Code 3661),
office machines (SIC Code 3579) and photocopy machines (SIC Code 3861). Although
subpart TTT defines EMI/RFI shielding coating, no VOC content limit is given. While the
standard defines the affected facility as spray booths, all VOC emissions that are caused by
coating application must be included in calculating a facility's compliance status (i.e., flash-off and
curing emissions are also subject). Add-on control devices can be used as an alternative means of
compliance, as determined on a case-by-case basis by the Administrator. If add-on controls are
used, the owner or operator must demonstrate that the volume-weighted average mass of VOC
emitted per unit volume of coating solids applied is within the applicable limit.
3.5.2 State Rules
In addition to Federal regulations, eight State and local air pollution control agencies have
regulations to control VOC from facilities that coat plastic parts (Delaware, California, Illinois,
Massachusetts, Michigan, New Hampshire, New York, and Tennessee). As would be expected,
the States that regulate the coating of plastic parts are the States where this industry is
concentrated. For example, California has many surface coating facilities generating plastic parts
for the computer, transportation, and aerospace industries. Similarly, Michigan has a high
concentration of plastic part surface coating associated with automobile manufacturing.
All of these State and local standards consist of a limit on the VOC content in coatings.
These limits range from 1.2 to 7.1 pound/gallon, as the VOC content limits are a function of the
part being coated (in some States). Appendix F summarizes the State and local plastic part
surface coating rules.
Some of these regulations include specific work practices limiting VOC from cleaning and
surface preparation as well as restrictions on the use of certain application equipment. All of the
rules allow for the use of control devices to achieve a VOC reduction equivalent to the coating
content limits. Currently, HAP content in plastic parts coatings is not regulated by any State.
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The standards for Tennessee, Illinois, New Hampshire, and Michigan apply to coating
operations for automotive and transportation equipment, business machines, and miscellaneous
plastic parts. These rules further divide the automotive sector by coating cure temperature (high
bake versus air dried), flexibility (flexible or nonflexible), and part location (exterior or interior).
Tennessee, Louisiana, and Wisconsin follow the business machines NSPS. New York establishes
a general coating limit for all plastic parts, and two air quality management districts in California
(South Coast and Bay Area) have specific limits based on coating type.
Rules also exist for other coating processes in related industries. The EPA has issued a
CTG for miscellaneous metal parts coating operations; issuing a CTG requires States under the
Act to promulgate RACT standards for miscellaneous metal parts coating operations in ozone
nonattainment areas. The format of the miscellaneous metal parts coating RACT standards for
Tennessee, Illinois, New Hampshire, and Michigan are similar to their plastic part coating
standards. These State rules include the same work practice standards and control device
requirements for plastic parts coating operations and for miscellaneous metal parts coating
operations.
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4.0 REFERENCES
1. U.S. Environmental Protection Agency. 1994. Alternative Control Techniques
Document: Surface Coating of Automotive/Transportation and Business Machines
Plastics Parts. EPA 453/R-94-017. Office of Air and Radiation, Office of Air Quality
Planning and Standards, Research Triangle Park, NC.
2. Margolis, James. M. Editor. 1986. Decorating Plastics. Hanser Publishers, New
York, NY.
3. Satas, Donatas, Editor. 1986. Plastics Finishing and Decoration. Van Nostrand Reinhold
Company, New York, NY.
4. Summary of May 7, 1997 Meeting of the Truck Manufacturers' Association (TMA) and
EPA MACT Development Teams for Miscellaneous Metal Parts and Plastic Parts. 1997.
5. Berins, Michael L., Editor. 1991. Plastics Engineering Handbook of the Society of the
Plastics Industry, Inc. Chapman & Hall, New York, NY.
6. Janeen Art Studio. 1997. Company Profile. Available: http://www.janeen.com.
7. Stuart Plastics Ltd. Coatings Technology. 1997. The SPL Refinishing System.
Available: http://www.splct.com.
8. Roobol, Norman R. 1997. Industrial Painting Principles and Practices. Hanser Gardner
Publications, Cincinnati, OH.
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