United States       Office of Air Quality         EPA 4S3/R-94-031
            Environmental Protection Planning and Standards       Aprll1994
            Agency           Research Triangle Park NC 27711

            Air



&EPA     Alternative Control

            Techniques Document:


            Automobile Refinishing

-------

-------
                                           EPA-453/R-94-031
Alternative Control Techniques Document-
             Automobile Refinishing
                  Emissions Standards Division
             U.S. ENVIRONMENTAL PROTECTION AGENCY
                   Office of Air and Radiation
              Office of Air Quality Planning and Standards
              Research Triangle Park, North Carolina 27711
                        April 1994

-------
This report has been reviewed by the Emission Standards Division of
the Office of Air Quality Planning and Standards,  EPA, and approved
for publication.   Mention of trade names  or  commercial products is
not intended to constitute endorsement or recommendation for use.
Copies of  this report  are  available through the Library Services
Office  (MD-35),  U.S.  Environmental Protection  Agency,  Research
Triangle Park,  N.C. 27711,  Technology Transfer Network  (TTKp under
the  Clean Air  Act Amendments Main  Menu,   Title  1,  Policy  and
Guidance,  or from National Technical  Information  Services,  5285
Port Royal Road, Springfield, Virginia 22161, (800) 553-NTIS.

-------
                             NOTICE               ;

     There  are  no planned  changes to  this document.   However,
corrections or updates sometimes become necessary.  Submission .of
a copy of the form below will ensure you receive any supplement or
change to this report that is published in the next twelve months.
Comments may be sent to the same address.
TO:  Emission Standards Division
     -MD-13      .                        •
     U.S. Environmental Protection Agency           .
     Research Triangle Park, NC  27711

ATTN: Mr. Mark Morris

          Please  forward  any supplement or  change  to EPA Report
Number EPA/450/R-94-031, "Alternative Control Techniques Document:
Automobile Refinishing" to the address below.

-------

-------
                        TABLE OF CONTENTS

                                                             Page

1.0  INTRODUCTION .  .  ... . .  .  .  .  .  . -.  . '.  -  .  -.  -  -      1-1

2.0  INDUSTRY DESCRIPTION . . .  .	      2-1

     2.1  Industry Overview	      2-1

          2.1.1  Coating Manufacturers	      2-1
          2.1.2  Coating Distributors ...........      2-2
          2.1.3  Body Shops	 .	      2-3

     2.2  Coating Types and Preparation	      2-4

          2.2.1  Lacquer Coatings 	  ......      2-5
          2.2.2  "Enamel Coatings  .	      2-5
          2.2.3  ,Urethane Coatings1  ...........      2-5
          2.2.4  Waterborne Coatings  .	      2-6
          2.2.5  Additives and Specialty Coatings ....   ,   2-6
          2.2.6  Coating Preparation  .	      2-6
          2.2.7  Coating Systems	      2-7

     2.3  Process Steps and Materials .	      2-7

          2.3.1  Surface Preparation	      2-7
          2.3.2  Primer Application	      2-8
          2.3.3  Primer Surfacer Application  	      2-9
          2.3.4  Primer Sealer Application  .. . .. ..      2-9
          2.3.5  Topcoat Application  ..........      2-9

     2."4  Preparation Stations	     2-11

     2.5  Spray  Booths	     2-11

     2.6  Spray  Equipment  ..........	     2-15

          2.6.1  Conventional Air Spray Guns	     2-16
          2.6.2  High-Volume, Low-Pressure Spray Guns . .     2-16
          2.6.3  Low-Volume, Low-Pressure Spray Guns  . .     2-18
          2.6.4  Electrostatic  Spray Guns . .	     2-18

     2.7  Equipment Cleaning	    2-19

     2.8  References   .......  	  ....    2-24

 3.0  EMISSION CONTROL TECHNIQUES	     3-1

     3.1  Introduction	   3'1

          3.1.2  Coating VOC Content	     3-2
                                ii

-------
                  TABLE OF CONTENTS  (continued)
                                                             Page
     3.2  Emission Reductions from Surface Preparation   I.
          Products	[     3"3

     3.3  Emission Reductions from Coating Applications  . ,     3-3

          3.3.1  Low-VOC Coatings	;     3-3
          3.3.2  High-Transfer-Efficiency Spray Equipment i     3-9
          3.3.3  New Developments in Spray Equipment  .  .      3-9

     3.4  Emission Reductions from Equipment Cleaning .  . j    3-10
     3.5  Existing State Regulations  	 !    3-11

          3.5.1  New Jersey	[    3-11
          3.5.2 'New York City	     3-11
          3.5.3  Texas	;    3-11
          3.5.4  California	     3-13

     3.6  Add-On Controls	.-  • .    3-13
     3.7  Emission Reductions from Improved Housekeeping -
          Practices and Training Programs	-  • ;    3-13
     3.8  References	-	;    3-15

4.0  BASELINE EMISSIONS AND EMISSION REDUCTIONS	!     4-1

     4.1  Surface Preparation .  .  . .. .  .  .	     . 4"1

          4.1.1  Baseline Volatile Organic Compound      j
                 Emissions from Surface Preparation  . .  .|     4-1
          4.1.2  Reduction of Volatile Organic Compound  i
                 Emissions from Surface Preparation  . .  .;     4-6
                                                         i
     4.2  Coating Application	•'     4~7

          4.2.1  Baseline Volatile Organic Compound      i
                 Emissions from  Coating Applications  . .[     4-7
          4.2.2  Reduction of Volatile Organic Compound
                 Emissions from  Coating Applications  . .j     4-10

     4.3  Equipment Cleaning	     4-12
                                                         !      •
          4.3.1  Baseline Volatile Organic Compound
                 Emissions from  Equipment Cleaning   ...     4-12

                 4.3.1.1  Emissions from Gun Cleaners . .;     4-12
                 4.3.1.2  Emissions from Manual Gun      |   ,
                          Cleaning	,....;•  4-14
                  4.3.1.3  Total  Gun Cleaning Emissions  .j     4-15
4.3.2  Emission Reductions from Gun Cleaning
                                                              4-15
                                iii

-------
                  TABLE OF CONTENTS (continued)
     4.4  Reduction of Volatile Organic Compound Emissions
          from Improved Housekeeping Practices and Training
          Programs  .'	    4-17
     4.5  References	    4-18

5.0  COST IMPACTS . . . . "	     5-1

     5.1  Costs to Coating Manufacturers   ........     5-1

          5.1.1-.. Process Modifications	     5-1
          5.1.2  Disposal Costs	-     5-2
          5.1.3  Training Costs	. •  •  •     5"2
          5.1.4  Annual Costs to Coating Manufacturers   .     5-2

     5.2  Costs to Distributors	  .     5-4
     5.3  Costs to Body Shops .	     5-4

          5.3.1  Surface Preparation Product Costs   ...     5-4
          5.3.2  Training Costs  .	     5-4
          5.3.3  Infrared Heating  System Costs   .....     5-5
          5.3.4  Spray Gun Cleaning Costs	     5-5
          5.3.5  Potential Productivity Losses   	     5-6
          5.3.6  Annual Costs to Shops	     5-7

     5.4  Cost Effectiveness  •	-     5-8
     5.5  References	••	     5-9
                                 IV

-------
Figure 2-1.
Figure 2-2,

Figure 2-3.
Figure 2-4,
Figure 2-5,
                         LIST OF FIGURES
Typical infrared heating unit
Spray booth make-up and exhaust air
orientation	•....-.
Conventional spray equipment
Typical enclosed gun cleaner
Typical open gun cleaner  .  .
2-12

2-13
2-17
2-20
2-22

-------
TABLE 3-1.

TABLE 3-2.

TABLE 4-1.


TABLE 4-2.


TABLE 4-3.



TABLE 4-4.


TABLE 4-5.



TABLE 4-6,



TABLE 5-1.
           LIST OF  TABLES

                                              Page

COATING CONTROL OPTIONS   .........     3-5

EXISTING REGULATIONS  	  ....    3-12

1995 BASELINE VOLATILE ORGANIC COMPOUND
EMISSIONS  IN NONATTAINMENT AREAS  (tons/yr)     4-2

ANNUAL EMISSION REDUCTIONS IN NONATTAINMENT
AREAS  (tons/yr)	     4-3

1995 SURFACE PREPARATION  PRODUCT  USE,
EMISSIONS, AND EMISSION REDUCTIONS  IN
NONATTAINMENT AREAS   	     4-5

1995 VOLATILE  ORGANIC COMPOUND EMISSIONS IN
NONATTAINMENT  AREAS FROM  REFINISH COATINGS     4-8

ANNUAL EMISSION REDUCTIONS IN NONATTAINMENT
AREAS  FROM COATING CONTROL OPTIONS
 {tons/yr)   .	     4-11

1995 GUN  CLEANING  EMISSIONS  AND  EMISSION
REDUCTIONS IN  NONATTAINMENT  AREAS
 (tons/yr)   	••	     4-16

ANNUAL COSTS OF CONTROL TECHNIQUES (103 $)      5-3
                                 VI

-------

-------
                       1.0  INTRODUCTION

     This document provides  information on  alternative  control
techniques  (ACT)  for volatile  organic  compound (VOC)  emissions
from automobile  refinishing.
     This document contains  information on  emissions,
controls, control -options, and'costs that States   can use in
developing  rules.  The  document  presents options  only,  and
makes no recommendations.
     *
       As used in this document, the term "State" includes
State and local air pollution authorities.
                              l-l

-------

-------
                   2.0  INDUSTRY DESCRIPTION
    This  chapter  describes  the  automobile  refinish  industry.
Section 2.1 provides an industry overview.   Section 2.2
discusses the types of coatings used in refinishing.  Section
2.3 describes the;. process steps and materials involved in
refinishing.  Preparation stations are discussed in Section
2.4, spray booths in Section 2.5, spray equipment in
Section 2.6, and equipment cleaning in Section 2.7.
2.1 INDUSTRY OVERVIEW
    As  used in this document,  "automobile" refers  to passenger
cars,  vans, motorcycles, trucks, and all other mobile
equipment that is capable of being driven  or drawn upon a
highway, such as  farm machinery and construction equipment.
"Refinishing" refers to any coating applications (to  the
interior or  exterior bodies of automobiles) that occur
subsequent to those at original equipment  manufacturer  (OEM)
assembly plants,  and includes dock repair  of imported
automobiles  and dealer repair of transit damage before  the
sale of an automobile.
    The automobile refinish industry consists of manufacturers
that produce refinish coatings, distributors or  "jobbers" that
distribute  coatings and other equipment, and body shops that
repair  and  refinish automobiles.
2.1.1   COATING MANUFACTURERS
     In 1989, sales of automobile refinish coatings in the
United  States totalled  slightly over  $1 billion.1   Five
companies accounted for 95  percent of these sales:   E.I.
du  Pont de  Nemours  &  Company,  Inc.  (including  Nason™
Automotive  Finishes), PPG  Industries,  The  Sherwin-Williams

                              2-1

-------
Company, BASF Chemicals, and Akzo Coatings.2  Approximately
one dozen smaller manufacturers supply the remaining  .:
5 percent.3  In the last few years, however, several otiher
large foreign manufacturers have begun to enter the U.S.
market, namely, ICI Autocolor, Spies Hecker, and Herberts
Standox.                                               !
     The five major manufacturers  also produce  components  such
                                                       [
as catalysts, solvents  ("thinners" or  "reducers"), and I
additives for use with their coatings. Approximately two dozen
other U.S. manufacturers produce lower-cost coating components
that are marketed for use with the coatings produced by the
major manufacturers.4  However, the major manufacturers report
that these lower-cost components may reduce the overall
quality of their coatings and, consequently,  will not honor
their warranties if such components are added to their
products.5                                             i
2.1.2  COATING DISTRIBUTORS                            |
     Distributors of refinish coatings also sell mixing
components and other products used for refinishing, such as
mixing stations, infrared heating lamps, sandpaper, ancl
masking tape.  Some distributors also  sell equipment and
products necessary to perform body repairs.  Distributors
provide body shops with valuable product support services such
as training in new products and equipment, mixing of topcoat
                                                       j
colors, troubleshooting advice, and general product    i
information.                                           >
     Although at least one coating manufacturer, The
                             '
Sherwin-Williams Company, operates retail  stores that  j
distribute only Sherwin-Williams products,6 the large majority
of the approximately 5,000 distributorships in  the United
States are not owned or operated by coating manufacturers.
Another 10,000 body part distributors  also sell refinish
products.7  Both types of distributorships are  known as paint,
body supply, and equipment  (PBE) specialists, and are  commonly
referred to as  "jobbers" or  "refinish  jobbers."
                              2-2

-------
2.1.3  BODY SHOPS         .
     There  are  approximately  50,000  body  shops  of various sizes
and technology levels in the U.S.,8'9'10 including small-size
shops, medium-size shops, shops at new car dealerships, and
large "production" shops.  The work performed by most small-
and medium-size body shops,  which comprise most of the
industry, is somewhat confined to repairing and refinishing
small portions of an automobile (e.g., a panel, or a "spot" on
a panel).  About 90 percent of refinish work performed is spot
repair.11'12 "Sixty percent of new-car dealerships
(approximately 13,500 facilities nationwide) reportedly
operate body shops.13 .. New-car dealers refinish not only new
cars damaged in shipment, but also cars that are brought in by
customers for repair.  Other types of shops specialize in
repainting entire automobiles and are often referred to as
"production" shops.
     Although body shops  in  some areas of the United States
must obtain permits or licenses to operate, painters are
rarely required to be licensed.14'15  Painter  training is
often provided by coating manufacturers and distributors and
by trade organizations, but no formal apprenticeship programs
have been instituted by the industry.                        :
     In contrast,  the refinish industry in several  European
countries is reportedly structured differently.  For instance,
in Germany, the refinish industry comprises large,
sophisticated  shops.^  In Holland, painters are required  to
be trained, pass a test, and obtain a license.1"7   In several
European countries, painters usually participate in
apprenticeship programs.  These apprenticeships are not
usually  mandatory, but are part of  the European culture.18
     The refinish industry in the United States is a dynamic
industry that  has changed dramatically in the  past decade.19
The  industry is shifting away from  a  large number  of small
facilities toward fewer, larger shops, primarily because of
worker health  and safety issues and hazardous  waste management
concerns.20  It is estimated that there  were  approximately

                              2-3

-------
125,000 shops in operation in 1976, but by 1993 the number
decreased to approximately 50,000.21                   !
2.2  COATING TYPES  AND PREPARATION                     ;
     The main categories  of  coatings  are  primers  and topcoats.
The primer category consists of pretreatment wash primers,
primers, primer surfacers, and primer sealers.  Topcoats are
applied over the primer coats and provide the final color to
                                                       i
the refinished area.
     Primers and topcoats can be classified as lacquer,  enamel,
or urethane  coatings.  These coatings differ  in their  i
chemistry, durability, and VOC  content.  Lacquer coatings cure
by solvent evaporation^only.  Enamel and urethane coatings
cure by solvent evaporation and chemical cross-linking
reactions.22                                           i
     Lacquers and some types of enamel coatings consist! mainly
of pigment,  resin,  and solvent  (thinner  or  reducer).  The
resin  and pigment  are collectively referred to as  coating
"solids" or "nonvolatiles" because they  remain on  the  j
substrate to form  the dry film.   Solvents  suspend  the solids
in solution and reduce the viscosity so  that  the coating  flows
into a uniform film on the  substrate.  The solvents evaporate,
and  only  trace quantities remain in  the  film  on  the substrate.
In addition to the coating  components discussed  above,
urethanes and some enamel coatings use catalysts (or
hardeners)  to initiate the  chemical  cross-linking.
     Urethane coatings typically have a  much  higher volume
percent solids than lacquers and a slightly higher percentage
than enamels.  This is an important  feature because, as
mentioned above,  the coating solids  are the permanent part of
the  paint that remain on the surface as a film.   The greater
the  solids  content of a coating, the less coating required to
obtain the  desired film thickness.                    I
     The coatings  applied by body shops  differ from those
applied by OEM's.   OEM facilities use coatings that require
temperatures up to 400 °F (204 °C) to cure the paint.  This is
possible because no temperature-sensitive materials have yet
                                                       I
                               2-4                     ;

-------
been installed in the automobile.  Body shops, on the other
hand, must use coatings that cure at low temperatures (less
than 150 °F  [66 °C])  to avoid damaging the automobile's
upholstery, glass, wiring, or plastic components.
2.2.1  Lacquer Coatings                                  -
     Lacquers were one of  the first types of coatings used  on
automobiles.  Lacquers dry faster than most enamels  or
urethanes and, when dry, can be buffed to remove surface
imperfections.  These characteristics are attractive to body
shops that do 'not have spray booths because the rapid drying
helps minimize the opportunity for dirt  to be trapped in the
wet  coating.  :0ne disadvantage of  lacquers  is that time and
labor must be expended in buffing-, (compounding) lacquer
finishes to  achieve full luster.23  Another disadvantage is
that lacquer finishes are not as durable as enamel and
urethane finishes.
2.2.2  Enamel Coatings
     Enamel coatings,  either alkyd or acrylic, have  long been
used in the  automobile refinish  industry.   Alkyd  enamel  is a
chemical combination  of an  alcohol,  an  acid,  and  an  oil.
Developed  in 1929, alkyd  enamels are less expensive  than
acrylic enamels but not as  durable.   Some acrylic enamels
require hardeners to  promote curing.  Both types  of  enamels
have a natural high gloss and do not require compounding to
remove surface  imperfections.   Some enamel coatings  can be
polished,  if necessary,  to  remove  trapped dirt or dust.
2.2.3  Urethane  Coatings
     Urethane coatings are typically  formed by a  reaction
between a  hydroxyl-containing material  and a polyisocyanate
hardener.   Their use  is growing because of their superior
gloss  retention and durability.   They are frequently used by
 the more  technically sophisticated body shops for complete
 refinish  jobs,  such as refinishing of fleet vehicles.24
     Urethane coatings dry more  slowly  than lacquers and
 enamels,  and spray booths may be necessary to reduce drying
 time and provide a clean, dust-free curing environment.  The

                               2-5

-------
possible presence of trace amounts of residual isocyanates
requires painters to use an air-supplied respirator to 'reduce
worker exposure.  Isocyanate-free hardeners are available for
use in some coating systems.25
2.2.4  Waterborne Coatings                             i
                                                 <
    A waterborne coating contains more  than 5  weight-percent
water in its volatile fraction.26/27  Like enamel and urethane
coatings, waterborne coatings dry relatively slowly.  The use
of a spray booth may be necessary to prevent contamination,
and infrared heating equipment may be necessary to facilitate
drying.          .                                      !
2.2.5  Additives and Specialty Coatings                j
    Some additives and specialty coatings are necessary for
unusual performance requirements, and are used in relatively
small amounts to impart or improve desirable properties.
Problems such as "fish eye" defects  (a surface imperfection
that can occur when the old finish contains silicone) can "be
prevented by the use of additives.  Additives and specialty
coatings include adhesion promoters, uniform finish blenders,
elastomeric materials for flexible plastic parts, gloss
flatteners, and anti-glare/safety coatings.
2.2.6  Coating Preparation
                                                       i
    Most coatings are mixed with additional solvents (and
sometimes catalysts) prior to application to ensure prpper
drying time, adhesion, appearance, and  color-match.   Topcoats
in particular must be mixed exactly  according  to the
manufacturer's instructions because  even a slight deviation
                                                       I
may result in unacceptable,finish quality.             j
                                                       I
    Many shops order topcoats to match the automobile being
refinished from  local automotive paint  distributors,   pthers
mix their own colors using mixing stations.  A mixing station
typically consists of a microfiche viewer or a computer that
contains the coating manufacturer's  mixing instructions,  a
digital  scale, and a mixing machine.  Shops that use  mixing
stations typically stock only a few  primary colors,  from which
almost any OEM color can be produced.28  According  to an
                                                    1   i
                              2-6

-------
industry survey, about one-half of all shops own mixing
machines.29  Almost all large volume or sophisticated shops
own mixing stations, but few small shops  (those employing only
one or two painters) own them.30
     Shops  that mix their own coatings  strive to mix as  little
as possible to complete a job, but always with a slight excess
to ensure that enough is available to complete the job.  By
minimizing the excess, the shop minimizes the cost of
materials and the amount and cost of. hazardous coating waste
disposal .."'•'.
2.2.7  Coating Systems
     All of the major coating manufacturers market  specific
brands of primer'and .topcoat products as  "systems."  All of
the coatings within a particular manufacturer's coating system
are compatible and, according to the manufacturers,  should be
used exactly according to instructions and never interchanged
with coatings from other systems,.3?-  Problems with adhesion,
durability, and recoatability are reportedly common  if coating
systems are not maintained.32
2.3  PROCESS STEPS AND MATERIALS
     The procedures for refinishing automobiles vary from shop
to shop; however, some basic steps are followed, whether the
job is to  repair a spot, panel, or entire automobile.
Generally,  the surface is thoroughly cleaned to ensure proper
adhesion of the  coating, the metal surface  is -,primed, a
topcoat is  applied, and  the  spray equipment  is  cleaned.
     The  following subsections describe the surface preparation
and coating application  processes.  The spray equipment
cleaning process is discussed in Section  2.6.
2.3.1  Surface  Preparation                         .  <
     The  first step in the refinish process is preparing the
surface.   The  surface  is normally washed  with detergent and
water and  allowed  to dry.  It is then  cleaned with  either
solvent or a solvent-based surface preparation  product
 (solvent wipe)  to  ensure removal of all remaining wax,  grease,
and other  contaminants.                           '.

                              2-7

-------
     Surface  preparation products  generally  contain  solvents
(toluene, xylene, and petroleum distillates) and
surfactants.33  These products are wiped off after they have
effectively dissolved the wax and grease from the surface.
This step is important to avoid contamination and ensure
proper adhesion of the coatings, and is necessary even if the
existing paint does not have to be removed or if the parts to
be coated are new.  Some shops use waterborne, low-VOC|surface
preparation products instead of solventborne products. j These
products are discussed in more detail in Chapter 3.0.
     If  an existing primer/topcoat is in good condition (no
chips or cracks),' the new paint can be applied directly on top
of it by merely "" scuff -sanding"  (or roughening) the surface to
promote adhesion.  If the existing finish has imperfections or
the part has been damaged in an accident, the old finish
should be completely removed down to bare metal.
     Removal  of old paint is by one of three methods:   j(l) by
sanding  (best for small  areas),  (2) with paint removers  (which
typically contain solvents  such as methylene chloride,|
methanol, and ammonia, and  are most efficient for large areas
and  complete panels), or (3) by sand blasting  (best for
complete automobiles or  extremely large areas).34'35   The
paint removal step is followed by a  final solvent wipe I
2.3.2  Primer Application
     Before any coatings are applied to bare metal,  thei surface
should be treated with  a metal  conditioner  to etch  the! surface
and  prevent  flash rusting,  which  can occur  from bare metal
exposure to  the  atmosphere.  Metal conditioning can be
achieved using a hand-applied  acidic  conditioner, or by  the
application  of a pretreatment  wash  ("self-etching") primer,
that both etches and primes the  surface.  Pretreatment; wash
primers  contain  at  least 0.5 percent  acid by weight, and can
be applied prior to  the application  of  solventborne or'
waterborne coatings.  If a pretreatment wash primer is not
used, the conditioned surface  should be primed to provide
corrosion resistance and promote  adhesion.3^
                                                       i
                               2-8                      ;

-------
     The  term "precoat"  has been used  in  several State
automobile refinish rules to describe a bare metal coating
category.  A precoat is described as a coating that is applied
to bare metal prior to the application of waterborne coatings-.
When pretreatment wash primers cannot be used (i.e., when they
are incompatible with the substrate or other coatings),
primers or primer sealers can be used to prepare the surface
for subsequent waterborne coatings; therefore, a separate
"precoat" category is not necessary.
2.3.3  Primer Surfacer Application
     If imperfections  remain  in the surface after  primer
application, a primer surfacer is applied.  Primer surfacers
build film thickness in order to create a smooth surface after
sanding, and provide adhesion and corrosion resistance.
2.3.4  Primer Sealer Application
     If there are no surface  imperfections,  some shops apply
only a primer sealer to provide more corrosion resistance,
promote adhesion of subsequent coatings, and enhance the
uniform appearance of the topcoat.  Primer sealers prevent
dulling of the topcoat  caused by the penetration of topcoat
solvents into the primer and primer surfacer coats.
2.3.5  Topcoat Application
     The topcoat system, applied  after the surface is prepared
and  free of defects, provides  the  final  color and  appearance.
Topcoats may be  single-stage,  two-stage, or three-stage
coating systems.  Each  stage of a  two- or  three-stage system
directly impacts the durability of  the topcoat  system,  and  the
ability to successfully match  the  old paint color.
     Two-stage basecoat/clearcoat systems may have either a
solid  color  or a metallic basecoat, covered by  a  transparent
clearcoat for protection and gloss.  The basecoat  is
approximately one-third and the clearcoat  two-thirds of the
total  coating used.37'38'39  Two-stage systems  are popular
because  of their deep,  rich finish, which  reportedly cannot be
duplicated by a  single-stage coating.
                              2-9

-------
_
              Metallic finishes contain small metal flakes,  typically
         aluminum, which are  suspended  in a mixture of binders,
         solvent, and pigment.. Light reflects  off these metal flakes
         to produce  the metallic  effect.  Color-matching these coatings
         is difficult and  depends on the alignment of the metallic
         particles,  which  is  influenced by the  evaporation  rate;of the
         solvent.  OEM's use  metallic coatings  on at least  50 percent
         of all  new  automobiles.40                             '
              Three-stage systems consist of a basecoat,  midcoat,  and
         clearcoat.   The basecoat and midcoat account for about
         one-half of the coating  volume and  the clearcoat for   I
         one-half.41'42-  Three-stage refinish systems are often;used to
         match three-stage.OEM finishes.43
              Three-stage iridescent finishes are similar to metallic
         finishes; they contain flakes  of mica  in  the midcoat that
         reflect light to  produce an iridescent, or  "pearl", effect.
              As OEM topcoats have become more  complex,  the precise
         matching of original colors by painters has become morfe
         difficult.   Annual  changes in  OEM  color selections add; a
         dimension of difficulty  to achieving color-match.  An
         automobile  manufacturer  typically will introduce over  10 new
         colors  in a single  year.44  New  car colors  are  developed by
         coating manufacturers, who preview  them with automobile
         manufacturing stylists.   The automobile manufacturer  then
         determines  from market research  which  colors to use.
              Once a new color  has been selected, the coating
                                                                i
         manufacturers develop coatings that achieve the desired
         appearance  and performance specifications.  Trial  application
         by the  automobile manufacturer may  then take a  number of
         months  before the coating is approved  for line  application.
              The typical automobile painter, however, lacks this period
         of  "trial  application" and is  expected to meet  color
         specifications and  customer  satisfaction for every job,
         regardless  of previous experience  with a particular color.
         Although  refinish coating formulations are developed  for each
         OEM  color,  there  is often variability  in the  shade color,

                                        2-10

-------
which requires the painter to make adjustments to the formula.
Because of the difficulty of matching  certain colors, the
painter must sometimes refinish more of the automobile rather
than just the damaged portion.  This,  of course, increases
coating usage.
2.4  PREPARATION STATIONS
     Preparation of the surface for repainting and application
of the primer usually are done in open areas of body shops;
however, in some  shops these steps are performed in
preparation, or  "prep",  stations.  Prep stations typically are
ventilated and equipped  with plastic curtains to control dust
and coating overspray.   Many shops are equipped with portable
infrared heating "units to facilitate drying of primers during
cool and/or humid shop conditions.  Figure 2-1 presents a
diagram of a typical heating unit.
2.5  SPRAY BOOTHS
     Spray booths are clean,  well-lit,  and well-ventilated
.enclosures for coating operations.  Because of their longer
drying times, enamel, water-based, and urethane coatings are
best applied in a spray  booth  to minimize the possibility of
dirt adhering to  the wet coating.  Air is drawn into a spray
booth through filters  to assure a  flow of clean air past the
automobile being  painted.  This air hastens drying and
provides a safer  work  environment  for  the painter by removing
solvent vapors from the  booth.  Filters in the discharge from
the booth remove  coating overspray (the portion of the coating
solids that does  not adhere  to the surface being sprayed) from
the exhaust air.
     There are three types of spray booths used in the refinish
industry:  crossdraft, downdraft,  and  semi-downdraft  (Figure
2-2).  Traditionally,  the air  flow in  refinish spray booths
has been from one side of the  booth  to the other,  or
 "crossdraft."  In the  crossdraft design,  incoming  air  is
pulled into the  booth  through  filters  located in  the entrance
door.  The air travels along the  length of the  car and then
passes through coating arrestor  filters at the opposite  end,

                              2-11             '   '    .

-------
r
                     Figure 2-1.  Typical Infrared Heating Unit
                                        2-12

-------
                          T  T   T  T  I  f  T  f  T  " T
                              Downdraft
                               Make-up Air
                     j  i  m  i  m  I
                            Semi-downdraft
                              Crossdraft
Figure 2-2.  Spray booth make-up and exhaust air orientation
                                 2-13

-------
where coating overspray is removed.  The air then exits
through an exhaust stack, carrying with it any solvent vapors
or other VOC's.
     Downdraft booths  have a vertical  air  flow  (top  to  bottom)
and are considered state-of-the-art because they provide the
cleanest drying/curing environment.  In a downdraft booth,  the
air is pulled in through filters in the roof, travels down
                        '
over the top of the automobile, picks up coating solvent and
overspray, and passes into a, grate-covered pit in the floor of
the booth.
                                       ,
     The downdraft  booth is a better design than  the crossdraft
booth because the air is less turbulent, which helps minimize
the mixing of overspray with air in the rest of the booth.   In
addition, air circulation is more uniformly concentrated
around the automobile and solvent vapor is drawn down and away
from the painter's breathing zone.
     Downdraft booths  can utilize dry-filtration  or
wet-filtration  (waterwash) systems to capture coating
overspray.  In wet-filtration booths, water is used to capture
overspray.  Both types of filters only remove coating solids;
they do not reduce VOC emissions to the atmosphere.
     The semi-downdraft spray booth is a combination.of
crossdraft and downdraft booth designs.  Air enters the booth
through the ceiling and is discharged at the back of the
booth.  Air in a semi-downdraft spray booth is more turbulent
than in a downdraft booth but less turbulent than in a
                                                       s
crossdraft booth.
     In order to decrease the drying time after coating
application, most  shops with spray booths use heated air
drying systems.  Smaller  shops may use traveling ovens that
can be rolled out  for use  inside the booth after the
automobile has been sprayed.  Small, portable,, infrared
heating units are  also available either to warm metal  surfaces
prior to coating application or to speed the drying time'of
the repair.
                              2-14

-------
     Approximately 40 percent of all body shops own crossdraft
 booths  and .30  percent  own  downdraft  or  semi-downdraft
 booths.45  The portion that  can heat the booth air  is  not
 known.  As the refinish industry continues  to  move  away  from
 lacquer coatings  and toward  slower drying higher-solids  and
 waterborne coatings, shops that do not  already have spray
 booths  are expected  to purchase them.
 2 . 6  SPRAY EQUIPMENT
     Current practice in the refinish industry is to apply
 coatings with  hand-held spray  guns that use air pressure to
 atomize the  coating.   There  are two  basic types of  spray gun
 systems:   pressure-feed and  suction-feed.   In  a pressure-feed
.system, the  coating  is contained in  a "pot" that is connected
 by hose lines  to  the spray gun.   Compressed air introduced to
 the  pot pushes the liquid  through the hose  and out  of  the
 spray gun  nozzle.  Pressure-feed systems generally  require
 significantly  more coating than suction-feed because of  the
 amount  of  residual coating in  the pressure  pot and  hose  lines.
     In a suction-feed system,  coating is contained in a "cup"
 mounted on the spray gun.  The rapid flow of air through the
 air  line and spray gun creates a vacuum which  draws the
 coating from the  cup and forces it through  the gun  nozzle.
     Based on available data, it  is  clear that some spray
 equipment  is likely  to give  better transfer efficiency than
 others.  Simply defined, transfer efficiency is the ratio  of
 the  amount of  coating  solids deposited  onto the surface  of the
 coated  part  to the total amount of coating  solids that exit
                         .                           c
 the  gun nozzle.  Paint that  is sprayed  but  not deposited onto
 the  surface  is referred to as  "overspray."   Increased  transfer
 efficiency,  or reduction of  coating  overspray, has  a number  of
 benefits.  Because coating overspray releases  the same amount
 of solvent as  the coating  that adheres  to the  substrate,
 reducing overspray reduces VOC emissions.
     Less overspray also benefits the refinisher.   Solvent
 concentration  in  the booth is  reduced,  less time is spent
 applying coatings (because more reaches the substrate),  and

                              2-15

-------
solvent use for cleanup of overspray is reduced.       j
Additionally, a shop that uses high-transfer efficiency spray
equipment uses less coating, and therefore may also realize a
savings in coating costs.  The transfer efficiency of spray
guns vary dramatically depending on a number of factors;, such
as the shape of the surface being coated, type of gun, |
velocity of the aerosol, skill and diligence of the operator,
and extraneous air movement within the spray booth.    ',
2.6.1  Conventional Air Spray Guns
                                                       I
     Conventional  air  spray guns  are  suction-feed and are  the
standard method of applying coatings.  Figure 2-3 shows the
two basic type's of conventional spray guns: syphon-feed and
gravity-feed.  In syphon-feed guns the paint cup is attached
below the spray gun, and the rapid flow of air through the gun
creates a vacuum that siphons the coating out of the cup.
Gravity-feed guns, which have the paint cup attached above the
gun, require less air pressure to move the coating through the
                                                       i,
gun and provide substantially better transfer efficiency than
syphon-feed guns.46
     The air pressure  at  which conventional spray guns operate
is usually 30 to 90 pounds per square inch  (psi).  One pf the
major problems with these guns is that the high velocity of
the aerosol causes the coating particles to "bounce", which
increases overspray.  The transfer efficiency of conventional
spray guns is substantially lower than that of "high-volume,
low pressure" (HVLP). spray guns.                       i
2.6.2  High-Volume, Low-Pressure Spray Guns
           *
     High-volume,  low-pressure spray  guns use large volumes  of
air at low pressure (10 psi or less)  to atomize coatings.
                                                       i
Because the atomized spray leaves the gun at a lower velocity
than in conventional air spraying, there is less particle
"bounce."  As a result, higher transfer efficiency can be
achieved,  with overspray reportedly being reduced by 25 to 50
percent.47
     The air source in an HVLP spray  system can be a turbine or
conventional compressed air.  Both systems can be purchased to

                              2-16

-------
Syphon-Feed
Gravity-Feed
  Figure 2-3.   Conventional spray equipment
                        2-17

-------
handle multiple spray guns.  The materials of construction of
most HVLP systems are designed to be compatible with a full
range of coatings.  Many HVLP spray systems are designed to
atomize high-, medium-, and low-solids coatings.
     When first using HVLP spray equipment,  the  painter must
adjust to the different characteristics of the spray pattern.
Initially, HVLP spray guns are more difficult to use,
especially for color-matching, because the greater transfer
efficiency requires that the painter move the gun more iquickly
in order to avoid applying an excessively thick coat.  Thick
films can cause splotching, which occurs when solvent
initially trapped^ in the thicker coating escapes to the
surface and causes'a blemish.  Also, thicker films retard the
evaporation rate of the solvent, which can influence the
positioning of metallic flakes.  In addition, the HVLP spray
requires more skill to blend.48  Once a painter becomes
experienced with HVLP guns, however, these problems are
overcome, with a significant cost savings because the amount
of waste coatings can be reduced with no sacrifice in the
quality of the refinished surface.                  .   j   '   .
2.6.3  Low-Volume, Low-Pressure Spray Guns
     Low-volume,  low-pressure  (LVLP)  spray guns  are  quite
similar to HVLP spray guns in that atomized coatings are
released at lower pressure (9.5 to 10 psi) and lower velocity
than conventional air spray guns.  The transfer efficiency of
LVLP spray guns is reportedly about the same as for HVLP spray
guns.  The primary difference is that LVLP guns use a
substantially smaller volume of air for paint atomization  (45
to 60 percent less).  Consequently, energy costs for air
compression are less than with HVLP guns.49            i .
2.6.4  Electrostatic Spray Guns
     Electrostatic spray systems create an electrical potential
between the coating particles and the substrate.  The charged
coating particles are attracted to the substrate, thus
reducing overspray and increasing transfer efficiency. ',
                              2-18

-------
     Typical  electrostatic spray,systems  are pressure-feed.
A large amount of coating is contained in the hose that
connects the spray gun to the paint pot.   It must be removed
before" the next coating can be applied with the gun.  These
designs appear impractical for the refinish industry,
primarily because refinish facilities change coatings so
often.50  In addition, the cost of electrostatic spray systems
may be prohibitive for most body shops.51
     It  has been  reported  that  there  are  explosion and
electrocution risks associated with use of electrostatic spray
guns unless very strict operating procedures are observed.52
Foremost, it is necessary to establish and maintain proper
electrical grounding -of all metallic objects in electrostatic
spray areas,  especially solvent and paint containers.  If
improperly grounded, these objects can develop high-voltage
charges as they come in contact with the electrified air
molecules and paint molecules.   A spark near these objects may
easily ignite any surrounding solvent vapors.53  Users of
electrostatic spray equipment should carefully observe all
manufacturers' operating procedures.
2.7  EQUIPMENT CLEANING         .   •   •
     Spray equipment can be cleaned manually or with any  of
several types of gun cleaning systems specifically designed
for this purpose.  About 60 percent of all body shops
reportedly use some type of gun cleaning system.54'55  Shops
that do not have spray gun cleaning systems usually rinse the
outside of the gun and cup, add solvent to the cup, and then
spray the solvent into the air or into a drum set aside for
spent solvent.56
     An  enclosed  gun cleaner or washer  (Figure  2-4)  consists of
a closed container  (much like an automatic dishwasher with a
door or top that can be opened and closed) fitted with
cleaning connections.  The spray gun is attached to a
connection,  and solvent is pumped through the gun and onto the
exterior of the gun.  The paint cup is also placed in the
cleaner, where the interior and exterior are sprayed with

                             2-19

-------
 Spray Nozzle
   Gun Support
  Pump Tubing
   Inlet Fitter
  and Tubing
Solvent Basin
                                                                  Pump
          Figure 2-4.  Typical enclosed gun cleaner
                                  2-20

-------
solvent.  Many gun-cleaners are capable of cleaning two guns
and cups per cleaning and are typically designed to clean
other equipment such as paint stirrers and strainers.
Cleaning solvent falls back into the cleaner's solvent
reservoir for recirculation.  Solvent is recirculated until it
is too contaminated for further use.  Some enclosed gun
cleaners are equipped with a second solvent reservoir that
contains virgin solvent that is used as a final rinse.
    A typical  open gun cleaner,  shown in  Figure  2-5,  consists
of a basin similar to a sink in which the operator washes the
outside of the. gun under a solvent stream.  The gun cup is
filled with recirculated solvent, the gun tip is placed into a
canister attached .to the basin, and suction draws the solvent
from the cup through the gun.  The operator then removes the
cup, places the gun's suction stem under the clean solvent
spigot, pulls the trigger, and pumps solvent through the gun.
The solvent gravitates to the bottom of the basin and drains
through a small hole to a reservoir that supplies solvent to
the recirculation pump.  The recirculating solvent is changed
when it no longer cleans satisfactorily.
    Waste  solvents generated by spray equipment  cleaning are
often disposed of by evaporation  (via spraying into the air,
or by placing in open drums) or incineration, or are reclaimed
via distillation.  Solvent can be reclaimed either at the shop
or Off-site.  Off-site solvent reclaimers collect spent
solvent from body shops, distill it, and return clean solvent
to the shops.  Some companies provide this service only for
those shops that rent their gun cleaning systems.
    In-house recycling can be  as simple as letting spent
solvents settle and decanting the "clean" layer for reuse.
This method, gravity separation, is used where the purity of
the solvent is not critical.  Some on-site distillation units
produce a more refined solvent, which reduces the amount of
new solvent that must be purchased and eliminates disposal
fees for the reclaimed solvent.
                              2-21

-------
Figure 2-5.
Typical open gun cleaner
      2-22

-------
     Care must be  taken when  a  solvent  reclaim unit  is to be
placed in use.   Solvents are combustible and can also be an
explosion hazard.57  Explosion hazards are possible from the
distillation residues that contain nitrocellulose.
Nitrocellulose is found in lacquer paint but would not be
expected in enamels and urethanes.58  In addition, some
on-site reclaimers are hot explosion-proof and may pose a
hazard when operated near other non-explosion-proof electrical
equipment.   It is recommended that reclaim equipment be
operated outdoors and away from spark-producing equipment,  and
that the power is turned off when the machine is being
emptied.59    •'    •
     The use of  solvent  for gun cleaning can reportedly  be
reduced by using teflon-lined paint cups, which makes paint
removal easier.  Some facilities use a small plastic liner
inside the paint cup to make cleanup easier and reduce solvent
use.  The paint-covered plastic liner is discarded after each
use and the paint cup remains essentially free of paint.
                              2-23

-------
2.8  REFERENCES
1.   Rauch Associates,  Inc.   The Rauch Guide  to  the  U.  S.  Paint
    .Industry.   ISBN 0-932157-00-09.   1990.   p.  85.

2.   National  Paint and Coatings Association,  NPCA Automotive
     Refinish  Coalition's  Estimates  of 1990 National Baseline
     VOC Emissions  from the  Automotive Refinish  Industry.
     Washington,  DC.  March  1992.

3.   Telseon.   Sullivan, J.,  Radian  Corporation,  with  '
     Schultz,  K.  R.,. E.  I. du Pont de  Nemours &  Company,  Inc.
     April 9,  1993.   Estimate of the number of refinishing
     coating manufacturers in the United States.

4.   Ref.  3    •'        :                                i     . '

5.   Letter from Sell,  J., Automotive  Refinish Coalition  to
     Jordan, B.,  EPA/CPB.  December  2, 1991.   Automotive
     Refinish  Coalition's  additional comments concerning
     technical  and  factual issues raised by the  study.  |p. 2.
                                                       i
6.   Ref.  1                                            !

7.   Letter from Roland, D.,  Automotive Service  Industry
     Association, to Ducey,  E.,  EPA/CPB.   January 22,  1993.
     Distributors of automotive  refinishing coatings.

8.   Collision Repair Industry.   Repair in the 90's.  Insight
     1:5.   February,  1991.                              i

9.   Letter from Graves, T.  J.,  Esq.,  National Paints and
     Coatings  Association, to South  Coast Air Quality
     Management District.  July  8, 1988.   Automobile
     refinishing industry  characterization and regulation.

10.  Meeting Summary from  Sullivan,  J. W., Radian Corporation,.
     to Schultz,  K.  R.,  E. I. Du Pont  de Nemours & Company,
     Inc.,  July 29,  1992.  Baseline  emission  estimates for the
     automobile refinishing  industry.

11.  Sell,  J.  Position  Paper of  the  NPCA Automotive  Refinish
     Coalition Concerning  Draft  Automobile Refinishing Control
     Techniques Guidelines.   In: National Air Pollution
     Control Techniques Advisory Committee.   Research Triangle
     Park,  N.C.  Office of Air Quality Planning  and Standards.
     November  21, 1991.  p.  1081.

12.  Schultz,  K.  R.,  E.  I. Du Pont de  .Nemours &  Company,  Inc.
     Comments  on the Automobile  Control Techniques Guideline
     Draft for NAPCTAC  Review on 11/21/91. In:   National Air
     Pollution Control  Techniques Advisory Committee.  Research
                              2-24

-------
     Triangle Park,  NC.   Office of Air Quality Planning and
     Standards.   November 21,  1991.   p.1070.

13.  Letter from Randall,  D.  A.,  Automotive Service
     Association,  to Ducey,  E.,  EPA/CPB.   June 27,  1991.
     Summary of  Automotive Refinishing Model Shop Emission
     Reduction Costs.

14.  Ref 13.

15.  Letter from French,  R.,  Collision Industry Conference,  to
     Ellen,  D.,  EPA/CPB.   October 11,  1992.   Body shop
     licensing.

16.  Telecon.  Shaw,  I.,  Radian Corporation,  with Sieradski,
     R.,  Akzo Coatings,  Inc.   October 12,  1992.   European
     automobile  refinishing industry.

17.  Ref.  16.       ' '"

18.  Ref.  16,

19.  Ref.  9.
20
     Ref.  11.
21. Memorandum from Campbell,  D.  L.,  Radian Corporation,  to
    Ducey,  E.,  EPA/CPB.   June  19,  199'0.   Trip report of site
    visits  with Sherwin-Williams  Sales'Manager,  Doug Smith.
22

23

24




25
     PPG Refinish Manual.

     Ref.  22.
PPG Industries.  1989.
    Memorandum from Ross  A.,  EPA/ORD,  to Ducey,  E.,  EPA/CPB.
    September 17,  1991.   Urethane Dispersions in Automotive
    Refinishing.

    Letter  from Sell,  J.,  Automotive Refinish Coalition to
    Jordan,  B., EPA/CPB.   December 2,  1991.   Automotive
    Refinish Coalition's  Additional Comments Concerning
    Technical and  Factual Issues Raised by the Study,   p.  2.

26. Athanson,  W. J.  World Automotive Chemical Coatings--
    Solvents Glossary.  D.  Van Nostrand Co.,  New York,  NY.
    1989.   p.  89.

27. U.  S. Environmental Protection Agency,  Office of Air
    Quality Planning and  Standards,  Glossary for Air
    Pollution Control  of  Industrial Coating Operations. Second
    Edition.   EPA-450/3-83-013R.  Research Triangle  Park,  NC.
    December 1983.   p. 23.
                             2-25

-------
28.



29.


30.

31.

32.


33.
Telecon.   Sullivan,  J.,  Radian  Corporation, with
Smith, D.,  Sherwin-Williams  Company.  January  10, 1992.
Paint mixing  and  recordkeeping.
34,

35.



36.



37,




38,
39
Babcox Publications.
'1993.   p.  51.

Ref. 28.
1993 Annual Industry Profile.   June
Ref.  11.  pp.  1076,  1081,  and  1082.               i

Clark, M. Common Complaints, Specific  Solutions.  Body
Shop  Business.   June 1990.  pp.  80-81.

Athey, C.,  C.  Hester, M. McLaughlin, R.M. Neulicht,  and
M.B.  Turner. •  Reduction of Volatile Organic  Compound
Emissions;from Automobile  Refinishing.   U.S.  Environmental
Protection  Agency, Research Triangle Park, North  Carolina.
EPA-450/3-88-009.  1988.                          !

Ref.  22.                                      .  '  '•

Telecon.  Sullivan,  J.,  Radian Corporation,  with  ;
Smith, D.,  Sherwin-Williams Company.   April  23, 1992.
Coating preparation.

Bay Area Air Quality, Management District.  Staff  Report  on
Proposed Regulation  8,  Rule 45 - Motor Vehicle  and Mobile
Equipment Coating Operations.   May 1,  1989.

Letter from Schultz,  K., E.I.  Du Pont  de Nemours  &
Company, Inc., to Brower,  G.,  New Jersey Department  of
Environmental  Protection.   January 24,  1989.  pp. ;3,4.
New Jersey  Refinish  Rule Development Procedures.

Inglis, R.  J.  BASF  Comments on Draft  Automobile  Control
Techniques  Guideline.   In:  National Air Pollution Control
Techniques  Advisory  Committee.  Research Triangle Park,
N.C.  Office of  Air  Quality Planning and Standards.
November 21, 1991.   Pp.  1012-1019.               j

Ocampo, G., Sherwin-Williams.   Comments on Draft
Automobile  Control Techniques  Guideline. In:  National
Air Pollution  Control Techniques Advisory Committee.
Research Triangle Park,  NC. Office of Air Quality
Planning and Standards.  November 21,  1991.   pp.  1045-
1048.
40.  Ref.  32.

41.  Ref.  38.

42.  Ref.  39.
                              2-26

-------
43. Ref.  22.

44. Ref.  38.

45. .Norton, J.   1992 .Annual  Industry  Profile.   Body Shop
    Business.  1JL:56.  June 1992.

46. Memorandum from Campbell, D.  L.,  Radian  Corporation,  to
    Ducey, E.,  EPA/CPB.  June 20,  1990.   Revised  trip  report--
    CBWD's, Inc.

47. Graco, Incorporated.  Product Information.  High Output
    HVLP  Sprayers.  1990.

48. Ref.  33.

49. Telecon,  Sullivan J., Radian  Corporation, with Thomas, M.,
    IWATA Paint Spray Equipment Manufacturing Company.
    November  26,  1992.   Low-volume low-pressure spray  guns.

50. Ref.  13

51. Ref.  33

52. Adams, J.   New  Application Methods and Techniques.  Binks
    Manufacturing Company.   Franklin  Park, IL.  In:  SPCC '91
    National  Conference  and  Exhibition.   Long Beach, CA.
    November  13,  1991.   p. 37-56.

53. Ref.  52.

54. Telecon.   Soderberg, E., Radian Corporation with Kusz, J.,
    Safety Kleen Corporation.  January 8,  1991.   Gun
    cleaners.

55. Telecon.   Campbell,  D.L., Radian  Corporation,  with
    Schultz,  K.,  E.I. Du Pont de  Nemours  & Company,  Inc.
    December  12,  1990.   Coating cost  and  industry
    characterization.
56.
57.
58.
59.
Ref. 54.
Gwynn, Sandra. Are Recylers Safe? Hammer and Dolly.
June 1992. pp. 37 and 38.
Ref. 57.
Ref. 57.
                              2-27

-------

-------
                3.0  EMISSION  CONTROL TECHNIQUES

3.1  INTRODUCTION
   The  steps involved  in automobile refinishing include surface
preparation, coating application, and spray equipment
cleaning.  Each of these steps can be a source of VOC
emissions.   (Techniques for estimating these emissions are
presented in Chapter 4.)  This chapter discusses techniques
for reducing VOC emissions from refinishing, which include:
   •     using low-VOC  surface  preparation  products;
  ••     using low-VOC  ("high-solids"  or  waterborne)  coatings;
   •     improving the  transfer efficiency  of spray equipment;
   •     using gun cleaning  equipment  that  recirculates  gun
        cleaning solvent;
   •     using add-on control devices;
   •     improving housekeeping practices and training programs;
        and
   •     reducing the number and severity of automobile
        collisions.            .      •
   VOC  emissions can be  reduced by using waterborne surface
preparation products,  and by using coatings that are
inherently low in VOC, such as urethanes.   Emissions could
also be reduced by reformulating conventional coatings to
lower their VOC content.  Improved transfer efficiency reduces
VOC emissions by decreasing the amount of coating overspray.
Gun cleaning equipment that controls evaporative losses also
recirculates solvent for several cleanings to reduce solvent
use.   Add-on control devices examined for this industry are
carbon adsorbers,  incinerators, and biofilters.
                              3-1

-------
   Improved housekeeping practices  include using  closed
containers for storing fresh and spent solvents.   Training
programs could focus on educating shop workers on ways to
reduce solvent and coating use.  Reducing the number and
severity of collisions involves equipping automobiles w,ith
safety features such as anti-lock brakes and "5-mile-per-hour"
bumpers.                                               '•
   Although beyond the  scope  of this  study,  increasing the
minimum allowable structural strength of new automobile
bumpers could 'be a pollution prevention step for this
industry.  The damage to sheet metal, lamps, etc., must, to
some degree, reflect the effectiveness of the bumper in
protecting the automobile from such damage.  Less damage
should translate to less coating use and reduced emissions.
   Low-VOC surface preparation products  are  discussed in
Section 3.2.and low-VOC primers and topcoats are discussed in
Section 3.3.  Gun cleaners are discussed in Section 3.4.
Existing State regulations for automobile refinishing are
presented in Section 3.5.  Add-on control devices are
discussed in Section 3.6.  The use of improved housekeeping
practices and training programs to reduce VOC emissions are
discussed in Section 3.7.               •               !
3.1.2  Coating VOC Content                             ;
     Before discussing  techniques  to  reduce the VOC emissions
from coating applications, it  is necessary to discuss the
methodology used to determine  the VOC content of coatings.  As
explained in Chapter 2, the  solids portion of a  coating
remains on the substrate to  form the film; therefore, the VOC
content of a coating ideally would be related to its volume
solids.  There is as yet, however, no generally  accepted
method for the determination of the solids content of  [
coatings.  This document continues the EPA's approach of
relating-the mass of VOC in  a  coating to the combined volumes
of VOC and solids, expressed as: mass of VOC per unit volume
of coating, minus volume of  water and any negligibly
photochemically reactive  ("exempt") compounds.   Unless

                              3-2

-------
 otherwise stated,  the VOC contents  discussed in this  document
 represent the amount of VOC in the  coating as it is applied,
 that is,  after the coating has been reduced or diluted  by the
 painter prior to application.
 3.2   EMISSION REDUCTIONS FROM  SURFACE  PREPARATION PRODUCTS
   VOC emissions can be reduced during surface preparation by
 using products that contain less VOC than  conventional
 products.   Conventional surface preparation products  average
 6.4  pounds of VOC  per gallon (Ib VOC/gal),  or 765 grams of VOC
 per  liter (g  VOC/-O-1  These products  consist mainly  of
 solvent,  the  active ingredient for  removing residual  grease
 and  wax from  the surface to be painted.
   The active ingredient in low-VOC surface preparation
 products  is detergent rather than solvent.   A gallon  of these
 products  contains  less than 1.7 Ib  VOC/gal  (200  g VOC/^);  more
 than a  70  percent  reduction over conventional products.2/3
 The  VOC contents of these  products  are not  expressible  in the
 same terms as  coatings because they contain no solids.
 Low-VOC surface  preparation products reportedly  work  as well
 as conventional  products,  but  they  must be  allowed to remain
 on the surface longer before being  wiped off and they require
 additional rubbing  for thorough removal.4*5   Conventional
 surface preparation products are wiped off  almost  immediately
 after being applied.   Low-VOC  surface  preparation products are
 already required in several  ozone nonattainment  areas of  the
 United States.
 3.3  EMISSION REDUCTIONS FROM  COATING  APPLICATIONS
   Emissions from coating applications  can  be reduced  by: (1)
 applying coatings with lower VOC content,  (2)  using spray
 equipment  that has  a  higher  transfer efficiency  so that less
 coating is wasted,  and (3). abatement.
 3.3.1  Low-VOC Coatings
   Information on low-VOC coatings was  gathered through  a
survey of the major manufacturers of automobile  refinish
coatings conducted by  the EPA  in March of 199O.6  The survey
revealed that all of  the major manufacturers  have developed

                              3-3

-------
coatings that contain substantially less VOC than conventional
coatings.  These coatings have been developed to comply with
several State regulations that mandate their use.     ;
   Table 3-1  lists  the various  coatings  used  in  automobile
refinishing and the VOC contents of conventional coatings.
This table also presents VOC limits for the various coatings,
which are organized into three options.
   The  limits of  Option  1 were  derived by evaluating  the
availability and reported limitations of the coatings included
in the survey.  Coatings at these limits are currently
available, and their use would not require the purchase of any
additional equipment. ' Therefore, shops at all levels of
technical sophistication should be able to use these coatings
with no loss of productivity or quality.              j
   The  Option 2 limits were  suggested by coating manufacturers
several years ago when they anticipated that such coatings
could be developed before they were required by a rule.  The
Option 2 primer/primer surfacer limit of 3.8 Ib VOC/gal  (455 g
VOC/£)  and the 5.0 Ib VOC/gal .(600 g VOC/*) limit for 3-stage
topcoats are claimed by manufacturers to be  "technology-
forcing" because there are no coatings  currently available at
these limits.  There are, however, 4.05 Ib VOC/gal primer
surfacers currently available.  Whether coatings could be
developed to meet the 3.8 and 5.0 Ib VOC/gal limits before
they are required by a rule is not known.             •
   The  VOC limits of  Option  3  are identical to the limits
determined to be Best Available Retrofit Control Technology
(BARCT) by the California Air Resources Board  (GARB)
(effective January 1, 1992 through December  31,  1994),! except
for the precoat.7  These coatings are  currently available;
however, their longer drying times would likely require  the
purchase of  additional equipment  (such as heating lamps) by
shops in geographical areas with weather conditions  less
favorable than California's.                          ;
   The  VOC limits presented in this document are lower than the
VOC contents of most refinish  coatings  currently used.   Newer

                              3-4                     :

-------
§
o
H
H
ft
O

J
o
F-l

8


i
H


I
O
H
 i
co

H
J



1






r7
1
O
X)
rH

JJ
a
Q)
a
o
o
u
-g









m
g
•H
4J
O
CN
G
O
•H
4J
a-
H
,c
u
•H
4J
a
o


1u
. en
2
1
i-H
C
Q

4J
a
§»
a
o
o
&
o
Cn
0)
j->
rt
O
S
•H
4J
O
O







in co in
• i • •
VO O3 f^O


in oo vo
• I • *
vo m *#

:in vo vo
t. .f. • •
tp ^^ -
VO P- P» VO

i i it
00 VO VO O
* • * •
in *# *f in



U
rt

i.
^
m

t i ti
4-) 0) 0)
C 6rH
Q) -H rt
g r( g
rt -u "^
 VD kD

i i i i
GO GO GO VO
• • • • .
in ^* in ^*








0)

Q) rt
Cn O
rt o
jj ^. j j_J Q
03 0) rH 4.) rt O
3 a) rt o aJ
03 tt> &1 S O O
AJ rH O S O M 0)
rt Cn rt fl a) rt Cn
o a J w m  rt
U -H rt rH 4J
aco mo co
O '
E-. m

o
<>'


0
*


0
•
c^





o
t^
















4J
i-H
rt
•H
U
0)
p
CO
                                    3-5

-------
technologies near commercialization hold promise of much
greater reductions.
   At least one manufacturer markets a solventborne 2.8 Ib
VOC/gal  (335 g VOC/O  coating which serves as both a primer
                                                       I ,
surfacer and primer  sealer.  This  coating does not take
significantly longer to dry  than conventional primers, and is
compatible with most of the  manufacturer's topcoat systems;
however, it is incompatible  with plastic substrates,8
   The VOC contents  of  conventional pretreatment wash primers
range from 5.8 to 6.5  Ib VOC/gal  (695 and 780 g VOC/-O ; the
average is approximately 6.3 Ib VOC/gal  (755 g VOC/-O .9  A
limit of 6.5 Ib VOC/gal  (780 g VOC/-O is included in all
options to ensure that this  bare metal coating can be  applied
in a thin film and that it will be compatible with subsequent
coatings.  No emission reductions  are anticipated from1
pretreatment wash primers, but significant reductions  could
not be expected since only about two percent of total
automobile refinish  emissions result from their application.
   Precoats  contain  between 4.6  and 7.1  Ib VOC/gal  (550 and 850
g VOC/£); the average is approximately 5.8 Ib VOC/gal  (695 g
VOC/-O .10  As discussed in Chapter 2, a separate category for
precoats is not necessary; therefore, none of the options
contain precoat categories.
   Since primer sealers are sometimes  used as bare  metal
coatings, the primer sealer  limits of the options  (discussed
below) were used to  estimate the emissions reductions  from
                                                       j
precoats.  The Option 1 and  2 limit of 4.6 Ib VOC/gal  (550 g
VOC/O would result  in about a 60  percent reduction in VOC
emissions from the average precoat; the Option 3 limit ;of 3.5
Ib VOC/gal (420 g VOC/£) would result in about an 80 percent
reduction.                                             |
   Conventional  primer/primer surfacers  contain between^ 4.6 and
7.1 Ib VOC/gal  (550  and 850  g VOC/-O ; the average is
approximately 5.7 Ib VOC/gal  (685  g VOC/-O .13-  The Option 1
                              3-6

-------
limit of 4.6 Ib VOC/gal  (550 g VOC/O would result in about a
55 percent reduction in VOC emissions from conventional
primer/primer surfacers; the Option 2 limit of 3.8 Ib VOC/gal
(455 g VOC/-O would result in about a 70 percent reduction;
the Option 3 limit of 2.8 Ib VOC/gal  (335 g VOC/*) would
result in about an 85 percent reduction.
   Conventional  primer sealers  typically contain between 5.0
and 6.7 Ib VOC/gal (600 and 805 g VOC/£); the "average is
approximately 6.3 Ib VOC/gal (755 g VOC/£)-12  The Option 1
and 2 limit of 4.6 Ib VOC/gal  (550 g VOC/*)  would result in
about a 75 percent reduction in VOC emissions from
conventional primer sealers; the Option  3 limit of 3.5 Ib
VOC/gal (420 g VOC/*) would result in about a 90 percent
reduction.
   As discussed  in Chapter 2,  topcoats are applied as a single
coating, or a two-stage  (basecoat/clearcoat) or three-stage
(basecoat/midcoat/clearcoat) system.  The following  equation
may be used to estimate the average VOC  content of a two-stage
topcoat:
                     VOC  =
                        a
                                   2 VOC
                                        CC
where:
   VOCa
   VOCbc
   voccc
Average VOC content  (Ib VOC/gal)
VOC content of basecoat  (Ib VOC/gal)
VOC content of clearcoat  (Ib VOC/gal)
This equation is used because the basecoat is approximately
one-third, and the clearcoat two-thirds, of the total film
thickness of a two-stage topcoat system.
   The  following equation may be used to estimate the average
VOC content of a three-stage system:
                              3-7

-------
                 voca =
                                       2 VOCCC
where:
   VOCa
   VOCbc
   VOCmc
   VOCCC
Average VOC content (Ib VOC/gal)
VOC content of basecoat (Ib VOC/gal)
VOC content of midcoat (Ib VOC/gal)
VOC content of clearcoat  (Ib VOC/gal)
This equation 'is used because the basecoat and midcoat each
are approximately one-quarter, and the clearcoat one-half, of
the total film thickness of a three-stage topcoat system.
   The  VOC contents  of  conventional  refinish topcoats  range
from 4.6 to 6.7 Ib VOC/gal  (550 to 805 g VOC/£) .3.3  The
average VOC contents of the different topcoat types are
presented in Table 3-1.  The emission reductions from
conventional topcoats that would result from a 5.0 Ib VOC/gal
(600 g VOC/-O limit range from about 70 percent for lacquers
to about 40 percent for all other topcoats.  The 5.2 Ib
VOC/gal  (625 g VOC/£) limit for 3-stage topcoats included  in
Option 1 would result in about a 30 percent reduction from
conventional coatings.
   The  use of topcoats  with VOC contents below the Option 3
limits reportedly can result in inferior color-match.  Coating
manufacturers contend that  the use of such  coatings could
actually increase VOC emissions because painters could be
forced to refinish substantially larger portions of an
automobile in order to blend the refinished area into the
existing finish.
   States may wish to consider different VOC limits for mobile
equipment  (e.g, farm machinery and construction equipment).
Several States have made such a distinction in their  rules.
Lower VOC limits for topcoats are reportedly  feasible for
mobile equipment because high gloss and color-match are  not  as
important as they are  in passenger  cars.
                               3-8

-------
   A rule containing VOC limits  for coatings  could  be
implemented and enforced at one or more points in .the coating
distribution chain.  In California, most rules require body
shops to keep records of the amount and VOC content of the
coatings they use.  If accurate records are kept, this is
undoubtedly the most accurate.  Shops maintain that such
recordkeeping is burdensome and decreases their productivity.
Such recordkeeping can also be burdensome to the State who
would have to review records for a large number of shops.
   A rule could  be written  such  that only compliant coatings
could be sold by distributors in the area affected by the
rule.  Recordkeeping at the shop level would be unnecessary if
only compliant coatings could be purchased by shops.  However,
the purchase of compliant coatings by shops does not guarantee
that coatings will not be diluted or reduced such that they
are no longer compliant.  Also,  shops could purchase their
coatings from distributors outside of the regulated area.
Such purchases may be reduced by a statewide rule.
   A rule enforced at the distributor .level may  decrease  the
burden on the State, since no shop records would be reviewed;
however, the State may still need to visit shops if their rule
contained shop requirements such as gun cleaners and high-
transfer-efficiency spray equipment.
3.3.2  High-Transfer-Efficiency Spray Equipment
   Although  transfer efficiency  is  a simple concept,  it is
difficult to use for regulatory purposes because of the many
factors that can affect it.  As a consequence, transfer
efficiency is not a quantifiable VOC control method, even
though it can have a significant effect on coating usage and
resulting emissions.  States may choose to publicize the
benefits of certain types of spray equipment  (such as HVLP),
or institute equipment standards that require their use.
3.3.3  New Developments in Spray Equipment
   In addition to  HVLP and  LVLP  spray equipment  designed  to
increase transfer efficiency, several manufacturers are
currently developing new types of spray equipment that may be

                              3-9

-------
feasible for use in automobile refinishing in the future.  One
manufacturer has developed a spray system that uses
supercritical carbon dioxide to replace a large portioii of the
solvent normally required for the spray application of:
coatings.  This system is currently infeasible for body shops
because existing automobile refinish coatings have yet to be
reformulated to allow application using this technology.
Aside from its current technical infeasibility, its high
capital cost ($50,000 to $70,000) makes it economically
infeasible for most body shops.  It is estimated that within 3
years such a system could be feasible for use in shops.14
3.4  EMISSIONS. REDUCTIONS FROM EQUIPMENT CLEANING
   Gun cleaning  is,a  source  of  solvent  emissions.   As  discussed
in Chapter 2, spray equipment can, be cleaned manually with
little to no control of evaporative emissions or with gun
cleaning equipment designed to reduce solvent consumption,
evaporation, and worker exposure.  Solvent may be emitted from
gun cleaning equipment both during the actual cleaning
operation (active losses) and during standby  (passive losses).
   As  discussed  in Chapter 2, most  body shops already  operate
gun cleaners.  State rules in several ozone nonattainment
                                                      I
areas already require their use  (Section 3.5) .  An estimated
60 percent reduction in VOC emissions is achieved by shops
that switch from cleaning guns manually to a gun cleaner.
   Gun cleaners  are of  two types, enclosed or open.  According
to a March,  1990, study comparing open and enclosed gun
cleaners, VOC emissions from open and enclosed cleaners are
about the same. 3-5  This report is based on comparisons of
passive and active VOC losses from four models of open gun
cleaners manufactured by the same company with five enclosed
units manufactured by other companies.  The study concluded
that the bowl-shape of open cleaners causes the cleaning
solvent to readily drain to the solvent reservoir, and the
small diameter of the solvent drain hole and hose mitigates
evaporative losses as well as the lid on enclosed systems..
                              3-10

-------
   In general,  neither  open nor  enclosed  gun  cleaners are
completely vapor-tight.'  For enclosed cleaners, a small amount
of solvent evaporates from the cleaning basin because of an
imperfect seal along the edge of the cleaner lid.  One of the
enclosed gun cleaner manufacturers in the above-mentioned
study has since redesigned its seal to reduce VOC leakage.
   Solvent  emissions  also  occur  from enclosed gun cleaners
while the lid is open for insertion and removal of the spray
guns.  Rapid opening and closing of the lid causes significant
turbulence of the air within the cleaner, which causes some
displacement of the solvent-laden air from the cleaner.  One
manufacturer above offers an optional speed-controlled lid
opener and closer designed to minimize turbulence and reduce
displacement of solvent-laden air.  The redesigned lid seal
and speed-controlled lid have not been tested to quantify
impacts on emissions.
3.5  EXISTING STATE REGULATIONS
   A number of  States containing ozone  nonattainment  areas have
already adopted rules for automobile refinishing.  A summary
of these regulations is presented in Table 3-2.  The following
subsections briefly describe the regulations in these States.
3.5.1  New Jersey
   The New  Jersey regulation  applies to the entire State,  and
specifies the maximum allowable VOC emissions per volume  of
coating.  No requirements are specified regarding surface
preparation or equipment cleaning operations.16
3.5.2  New York City
   The New  York City Metropolitan Area  regulation applies  to
the five boroughs of New York City and four  surrounding
counties.  The regulation limits the VOC content of automobile
refinish coatings applied.17
3.5.3  Texas
   In Texas,  automobile refinishing is  regulated under a rule
covering several types of surface coating processes.  The
Texas regulation limits the VOC  content of coatings and
surface preparation products in  all nonattainment areas.   Body

                              3-11

-------












1
H
§
3
t^
CD
&3
PS
CD
£3
rH
jj-4
CO
H


*
OJ
ro
W
I—I


H






















r4 JJ
Q) tn
C GJ
rc E
Q) 0)
_J t [
O-H
CD H





CQ
•H
E
•H
i-H <_<
°ti
5 t"
r^ *x^
__o
JH O
5 r*
JJ
o ""H
ri "*"**
**
in
CA
*"»





a *7
o jjd
CU-H-H 2.
U JJ E O £,

ft







Co
/it
CO
rl
rtj









0 g 0









o o
« •
og t» in
* CN
o in • ••
in • •• u> ^^
* ^Q &i ,O
VD "CO
^1* JJ *H •• *r™>
O • •• (0* JJ ft
«^J< ••inOiHOOtC 3rH
VD O JJ-'CO-OO Xi o — '
JJ Cti JJ •• •• CQ •• JJ JJ
n5 O •• CO" JJ CQ JJ O rH ^N^, rH
O O CQ (UnSMMccltDrc! MrH
UJHJH rtOO)
CQCJO ft&i&CUEHmw ptJO





/It ' jtt
UJ —U U)
C . CJ
£ H £







>1
JJ
nJ -H
>< U
0)
CO X
0) X! 0
HJ to ><
crj
> X S
Q) 0) QJ





CQ







H
•
OJ

o
o r-
u
rt co jj
»M • C
in SH 04 0) &i
3 u C
f> CO CO -H
0) in jj
•• in M $H GO rO • cti
JJ • fl) 0 • -H «* O
0) m -H tti ^ H °
E MO) •>>.••>,
JJ •• ft CQ •• U JJ JJ
CtJ JJ *^^ JJ *rH CC rH
Q) ret JH M cc> rH O nJ
5-)OQ)Q)OrHrj-H
jJUSEurtfto
CM CM CM CM H S CO






p*
vo
•






^1
•H
ril
rt
•H CQ "O
CO)
rl U U

IH S *O CQ
•H O r< Pjj

rt  H Xl
a) a-H >,g
JJ CU rt H
jj S ;CQ d o
CQ vH -H C IW
CO *O (ti
tt) JJ t-3 CO
^•1 JJ JJ JJ
•H fO ti ^t'H
jj (d fl) X) E
0) C (U CO H
tji JJ
o c re d M
JJ -H B a) 0)
fO E S
CO CQ E <1) O
•H -H >i-H
rH rH JJ 3 CO
ft ft-H D"d
& ftrH a) a
cd cc co j-i  ,Q O *O
3-12

-------
shops in these areas are also required to use enclosed gun
cleaners.1^
3.5.4  California
   Several  California air quality districts  have adopted rules
for automobile refinishing, including the Bay Area, South
Coast, Ventura, San Joaquin, Santa Barbara, and Mojave.
Others, such as San Diego and Sacramento, have rules in
development.  With minor differences, these rules contain the
same requirements determined to be the "best available"
control technology by CARB,19 including VOC content limits for
coatings and surface preparation products, and spray gun
efficiency and' cleaning requirements.
3.6  ADD-ON CONTROLS
   Add-on controls are used to remove VOC's  from spray booth
exhausts in a variety of industries.  They can be grouped into
two broad categories:  destructive and recovery devices.  The
most common destructive technique is incineration.  Recovery
techniques adsorb, scrub, or condense solvent and other VOC's
from the air.
   These devices  are.currently, economically infeasible for body
shops.  The annual operating cost of an incinerator is
estimated to be $120,000.20  The annual operating cost of a
carbon adsorber is estimated to be $40,000.21  These costs are
prohibitive to body shops, one-quarter of which have annual
.sales less than $100,000.22
   The intermittent spray booth activity in many shops also
makes add-on devices very expensive  on a cost per emission
reduction basis.  At least one manufacturer, however,  is
designing a lower cost incineration  system specifically  for
the process conditions of refinish spray booths.  Because of
the high costs of currently available add-on control devices,
they are not further discussed.
3.7  EMISSION REDUCTIONS FROM IMPROVED HOUSEKEEPING PRACTICES
   AND TRAINING PROGRAMS
   In addition to the emission reduction techniques already
described, solvent evaporation can be minimized through

                              3-13

-------
diligent housekeeping practices.  Shops can reduce VOC
emissions by storing fresh and spent solvent in closed
containers that decrease vapor loss by minimizing the amount
of time that solvent is exposed to the atmosphere.  Costing
waste can be minimized by mixing only as much coating as is
needed to complete a job.  Waste paint, spent solvent, and
sludge from gun cleaners and in-house distillation units
should also be stored in closed containers and disposed of
properly by transfer to designated hazardous waste management
facilities.  To assist local enforcement agencies in tracking
disposal and ensuring proper disposal, a manifest system
should be used.'.
   "Miscellaneous" .solvent  use  should also be minimized.   For
example, some shop employees use solvent to remove coating
overspray from spray booth walls..  Spray booth walls can be
cleaned with non-VOC products made specifically for this
purpose rather than solvent.  Several companies market
waterborne strippable coatings designed for spray booth walls.
When this coating becomes covered with overspray, it is pulled
off the booth walls, and another coat is applied.  This
process change can almost eliminate the need to use solvent to
clean booths.                                          ;
   Coating  use  (and  costs)  and  VOC  emissions  can also  be
reduced through training programs that explain why and how
solvent emissions contribute to unhealthful air, and teach
good work practices.  These programs could recommend the use
of higher-transfer-efficiency- spray equipment,  inform painters
of the importance of minimizing overspray, and teach methods
by which color-match can be achieved without extensively
diluting the coating with additional solvent.  Training
programs can also help painters select the correct types of
coatings to use on certain substrates and in certain
conditions (i.e., varying temperature or humidity) so that
jobs do not have to be redone.
                             3-14

-------
 3.8   REFERENCES
 1.
2.
3.
4.
5.
6.
7.

8.



9.
10.

11.

12.

13.

14.
 Letter from Ocampo,  G.P.,  The Sherwin-Williams  Company,
 to Ducey,  E.,  U.S.  Environmental  Protection Agency.
 October 30,  1990.

 South Coast Air Quality Management  District.  Staff
 Report on  Proposed  Rule 1151--Motor Vehicle and Mobile
 Equipment  Non-Assembly Line Coating Operations.   June
 16,  1988.

 State of California Air Resources Board.   Determination
 of Reasonably  Available Control Technology and  Best
 Available  Retrofit  Control Technology for Automobile
 Refinishing Operations.  January  8,  1991.

 Telecon.   Soderberg,  E., Radian Corporation, with
 Schultz, K., E.I. Du Pont  de  Nemours & Company,  Inc.
 February A,  1991.   Low-VOC surface  preparation
 products.

 Telecon.   Gilbert,  J.,  Radian Corporation,  with Torres,
 T.,  H Street Auto Body.  August 10,  1992.   Low-VOC
 refinishing products.

 Memorandum from Campbell,  D.L., Radian Corporation, to
 Ducey,  E.  EPA/CPB.   February  28,  1991.  Summary of
 Coating Manufacturer's  Survey Responses --  Automobile
 Refinishing CTG.
Ref. 3.

PPG Industries.
1993.
Product Bulletin No. 184.  December,
National Paint and Coatings Association.  NPCA
Automotive Refinish Coalition's Estimates of 1990
National Baseline VOC Emissions from the Automotive
Refinish Industry.  Washington, DC.  March 1992.  6 pp,

Ref. 9.

Ref. 9.

Ref. 9.

Ref. 9.

Telecon.  Morris, M., U.S. Environmental Protection
Agency, with West, T., Union Carbide.  April 11, 1994.
Carbon Dioxide Spray Systems.
                             3-15

-------
15.
16.
17.
18.
19.

20.




21.

22.
ENSR Consulting and Engineering.  Comparison of Solvent
Emissions from Two Types of Spray Gun Cleaning Systems.
Prepared for Safety-Kleen Corporation.  ENSR Document
No. 5831-005800.  March 1990.

New Jersey State Department of Environmental Protection
and Energy. Control and Prohibition of Air Pollution by
Volatile Organic Compounds.  Title 7, Chapter 27.  New
Jersey.  State Department of Environmental Protection
and Energy.  January 28, 1992.

New York State Department of Environmental
Conservation.  An Evaluation of Alternatives to Reduce
Emissions from Automobile Refinishing in New York, New
York.  New York State Department of Environmental
Conservation.  August 1987.

Texas Natural Resources Conservation Commission.
Control of Air Pollution from Volatile Organic !
Compounds. Regulation 5, Chapter 115, Subchapter E.
Austin, Texas.  November 10, 1993,

Ref. 7.

U. S. Environmental Protection Agency, Office of Air
Quality Planning and Standards.  OAQPS Control Cost
Manual.  Fourth Edition.  EPA 450/3-90-006.  Research
Triangle Park, NC.  January 1990.  pp. 4-1 to 4-44.
Ref. 20.

Babcox Publications.
p. 29.  June 1993.
1993 Annual Industry Profile.
                              3-16

-------
        4.0  BASELINE EMISSIONS AND EMISSION REDUCTIONS
     Volatile organic compound emissions  from automobile
refinishing occur during surface preparation, coating
application, and spray equipment cleaning.  This chapter
presents estimates of the VOC emissions from each of these
processes and emission reductions that can be achieved using
the control techniques described in Chapter 3.
     Since most  of  the automobile  refinish rules  developed by
States will be in effect by early 1995, projections of 1995
emissions were used as the "baseline" from which emission
reductions were measured. Considering the reductions already
achieved by State rules, baseline VOC emissions were estimated
for each refinish process, and are presented in Table 4-1.
Table 4-2 presents estimates of the reductions achievable
using the control techniques described in Chapter 3.
4.1  SURFACE PREPARATION
4.1.1  Baseline Volatile Organic Compound Emissions from
       Surface Preparation
     Emissions from surface preparation are a function  of  the
VOC content of the surface preparation product, the amount of
product used per refinish job, and the number of refinish jobs
performed.    As discussed in Chapter 3, several State
regulations require the use of low-VOC surface preparation
products.  For purposes of estimating baseline emissions it
was assumed that conventional surface preparation products
will continue to be used in unregulated areas; in States that
have rules,  it was assumed that products have the maximum VOC
content permitted by the limits of the respective rules.
     For  each refinish job, it was assumed that approximately

                              4-1

-------
o
  2
  o
1
M
J
W

3
CQ

in
en
en
H
m
d
i-H O
rt -H
JJ CO
o m
[H -rj
Q)
tn
d "H
3 (-<
UJ 5?
H
O
d
o
tn-H
d -U
•H rt
4J O
nJ -H
O i-l
o a
rt
d
o
0) -H
O 4-)
rt nj
LJ M
3 a
CO 0)










nS
CO

f£

















O O O O O
m o H f- r-
i U rt
(U -H Cn
m 44 d d

a) o o d
i-j >H m »w -H
rt -H nS
> > X rH g

S3 S3 EH U Cd



o
CO
in
m

OQ

U)
OS



0
in
o
M
m





m
in
in



m
0)

rt
•g
i=
§
-H
a
4J

rt
d
o
d
.
CO

•
£3

rH
CC
JJ
0
EH
                                      4-2

-------




td
*— *
S-l
"^v.
CO
8
AJ
w
a.
s
K
H
p~|
g
&
O

H
I
H
EH
U
D
Q
§
S
O
H
CO
CO
H
S
w
<
B
z
KC

.
OJ
1
•^
TABLE




CO
m
C S-i
O rt
rH
O


ro OJ
Cn
C3 C3
O-H
•H 4J
4J ft!
O* 8

03 CO
&}
G G
O-H
•H 4->
JJ rt
ao
0 U


rH 03
Cn
G G
O-H
•H JJ
4-> rt
.8-8



O
U 0)-H S
O U 4J ij
£* (C rt r-l
i *i i ^-i _t
S M rt o
o s aR
J CD fl) o
>H









rt
a)





H
t^  a\ in o '"],
n m oj 0
H




o
ooo o
in 03 CD o *x>
rn ro rH *





._ _ m
^ °) 0 0 H





CO
rt

Is

* 1 ^
CO C
>i 0)
jj • i
•H D 3
>^ cj ns -H
 £ X rH g G
0) fl) QJ nj 

G U. S. attainme •-H C (C O Jj £j O EH in cr\ rH II 5-1 rt cp »S Jaseline (C 4-3


-------
4 oz, or 0.25 pints (0.12 £),  of surface preparation product
are used.1"5  Approximately 19 million refinish jobs are
performed in the United States each year,6"8 and the number of
•jobs performed in a particular geographical area of the United
States is assumed to be a function the area's population.   The
number of refinish jobs performed in an area is estimated by
                                                       i
the following equation:
                        = JUS * (pa / PUS)
                                                          (4.1)
where:

     JUS  =


     PUS  -
               Number of  refinish jobs performed in area;
               Number of  refinish jobs performed in the  United
               States;
               Population of area;  and                 j
               U.S.  population.                         i
Census data for 1990 were used in this document to estimate
1995 populations.  The U.S. population in 1990 was
approximately 248,710,000.9  Population data for each
nonattainment area were compiled from available 1990
metropolitan area statistics.
     Annual surface preparation product use in an area is
estimated by the following equation:
                      SP= = Ja *  (0.25/8)
                                                          (4.2)
where:
     SPa
     Ja
     0.25

     8
               Area surface preparation product use (gal/yr};
               Number of refinish jobs performed in area;
               Pints of surface preparation product used per
               job; and
               Pints per gallon.
     As shown in Table 4-3, it is estimated that 226,000 gal/yr
                              4-4

-------
 TABLE 4-3.   1995 SURFACE PREPARATION PRODUCT USE,  EMISSIONS,
        AND  EMISSION REDUCTIONS IN NONATTAINMENT AREAS
Area
New Jersey
New York City'
Texas
•California
Remaining U.S.
Baseline
product use
(gal/yr)
7,280
16,590
17,730
51,320 -
133,030
Baseline
emissions
(tons/yr)
23
53
12
39
426
Emission
reductions
(tons/yr)
17
39
0
0
313
  nonattainment areas

Total U.S.
  nonattainment areas
225,950
553
369
                             4-5 •

-------
of surface preparation products are used in nonattainment
areas.                                                 !
     Baseline  emissions  from surface preparation were estimated
by the following equation:
                  ESp = SPa * VOCsp / 2,000
                                       (4.3)
where :
     E
      sp
     VOC
        sp
     2,000
 Area VOC emissions  from surface  preparation
 (Ib/yr);
 Area surface preparation product use
 (gal/yr);
"VOC content of surface preparation product
 (Ib VOC/gal); and
 Pounds per ton.
     The above equations were used to estimate 1995 baseline
VOC emissions from surface preparation in nonattainment areas
of the United States.  As shown in Table 4-3, emissions were
estimated separately for each nonattainment area with an
existing regulation, and for all unregulated  nonattainment
areas combined.
4.1.2  Reduction of Volatile Organic  Compound from Surface
       Preparation Operations
     The use of surface preparation products with lower VOC
contents will reduce VOC emissions.   Waterborne surface
preparation products with VOC contents below  1.7 Ib VOC/gal
 (204 g VOC/£) are currently  available.  The emission  ',
reductions  achieved in nonattainment  areas by using these  low-
VOC products  are presented in Table  4-3.  VOC emissions are
reduced by  about 70 percent.
                               4-6

-------
4.2  COATING APPLICATION
4.2.1  Baseline Volatile Organ-ic Compound Emissions from
       Coating Applications
    •Estimates  of  1995  VOC  emissions  from coating applications
were based on 1988 coating usage and emission estimates
provided by coating manufacturers10r11.  The amount of
coatings projected for application in nonattainment areas in
1995, and the resulting VOC emissions, are presented in Table
4-4.  Application of about 12 million gallons of coatings is
estimated to result in about 32,000 tons of VOC emissions.
Primer coatings account for approximately 23 percent of the
emissions,' topcoats for approximately 74 percent, and
specialty coatings for the remaining 3 percent.
     Emissions  from coating applications  are dependent  on
coating usage and VOC content.  The amount of coating .required
for a refinish job ultimately depends on the solids content of
the coating.  The relationship between the VOC  (predominantly
solvent) and solids in a solventborne coating was approximated
using the following equation:
                      Vs = 1 - (VOCC / d)
                                            (4.4)
where:
     V,
      s
     vocc
Volume solids content of coating  (fraction);
Solvent (VOC) content of coating  (Ib solvent/gal
coating);  and
Density of solvent  (Ib solvent/gal solvent).
     The amount of coating solids applied in the United States
was estimated by the following equation:
                          Cs  =  Cc  * Vs
                                            (4.5)
where:
               Gallons of coating solids applied in the United
               States;
                              4-7

-------
TABLE 4-4.  1995 VOLATILE ORGANIC COMPOUND EMISSIONS IN
      NONATTAINMENT AREAS  FROM REFINISH COATINGS   :
      Coating category
  Coatings
   applied
(103  gallons)
Emissions
(tons/yr)
Primers
  Pretreatment wash primer       210
  Precoat                         60
  Primer/primer  surfacer       1,600
  Primer sealer                  720

Topcoats
  Single stage
    Lacquer  ,                    600
    Enamel       ,              1,980
  Basecoat                     1,810
  Clearcoat                    4,640

Specialty                        260

Total                         11,880
                    650
                    170
                  4,260
                  2,170
                  1,800
                  5,240
                  5,340
                 11,520

                    910

                 32,050
                          4-8

-------
     Cc   =    Gallons of coatings applied in the United
               States; and
     Vs   =    Volume solids content of coating (fraction).

The amount of  coating solids applied  in a particular area of
the United, States is  assumed to be  a  function  of  the
population of  that area, and was  estimated by  the following
equation  :•'.„•
        sa
 =  C
                  (P
                                      PUS)
(4.6)
where :
     Cs
     Pa
     PUS
Gallons of solids applied in area;
Gallons of solids applied in the United States;
Population of area; and
U.S. population.
     By rearranging equation 4.5,  the amount of coating used in
a particular area  ("area coating use") can be  estimated by
dividing the amount of coating solids applied'in the area by
the coating VOC content that is typical or, in the case of
regulated areas, required in the area.  Area coating use was
estimated by the following equation:
-ca  -  '-sa
                                  /
                                     'sa
                                            (4.7)
where:
     cca
     Csa
     VSa
Area coating use  (gal/yr);
Gallons of coating solids applied in area; and
Volume solids content of coating  (a function of
the presence and stringency of the area's
applicable rule) expressed as a fraction.
     The VOC emissions in an area from coating applications
were estimated using the following equation:
                              4-9

-------
Et
                         (Cca * VOCC) / 2,000
(4.8)
where:
    •Et
     Cca
     VOCC
     2,000
 Area coating application emissions
  (tons/yr);
 Area coating use  (gal/yr);
 VOC content of coating  (Ib VOC/gal); and
 Pounds per ton.         v>
Equations 4.4 'through 4.8 were used for each coating category
and nonattainment area of the United States to estimate
baseline VOC emissions and emission reductions.
4.2.2 Reduction of Volatile Organic Compound Emissions from
       Coating Applications
     The use of  coatings  with VOC contents lower than those of
conventional coatings will reduce VOC emissions.  Table 4-5
presents the projected reductions from the use of coatings
that meet the limits of Options  1 through 3.  Option 1 reduces
baseline emissions by about 10,500 tons, or 33 percent; Option
2 reduces the baseline by about  11,200 tons, or 35 percent;
and Option 3 reduces the baseline by about 12,000 tons, or 38
percent.
     No emission reductions are anticipated in California
because by 1995 all nonattainment areas are expected to be
subject to rules at least as  stringent as Option 3.
Reductions of about 300 to 500 tons are expected in New Jersey
nonattainment areas, where the VOC limits of their existing
rule are higher than those .of Option 1.   Similar reductions
are expected in New York City, which, like New  Jersey, has
higher VOC limits than those  of  Option 1.  About 200  to 300
tons of reductions are expected  in nonattainment areas in
Texas.
                              4-10

-------
o

g
o
u
O
s
O
o
§
g
a
•w
g-
1
H ^-~
NONATTA
(tons/yr
s
H  m o l ^
_u __u 	 ^ *
^ "* ^ rH M
H rH


0 0
S S-'S 0 H S
^ ^ « : o H
rH H



° S
000 0 ^
in CN oo o VD UI
" " - „- o




§ § § s 1 §
m 0 r4, t^ "1 X
rH* r>r t>r r>r ^ ^
r-l CN CN CN ^ m





CO
0)
rt

• C
>i CO (1)
jj • g
•H • p C
S U rt -H
d) -H en nS
CO _*^ {5 f3 1 *
5-1 J-l 5-1 -H 4J
(u o o. d rt m
hj, rH 03 «W -H d rH
id *H rs O n$
> ^ K rH g d 4J
J5 S3 EH O Pi EH

























in
CTi
rH
II

$»l
id
0)
>,
0)
d
•H
iH
0)
CO
cd
ffl
Id
4-11

-------
4.3   EQUIPMENT  CLEANING
4.3.1  Baseline Volatile  Organic Compound.Emissions from
Equipment  Cleaning
    ••Emissions from cleaning spray equipment are a function of
the number of refinish jobs performed and the method of
cleaning.  A gun  is required  to be cleaned approximately four
times with each refinish  job.  Multiplying the  four cleanings
by the  19  million refinish jobs performed in the United States
annually,  it was  estimated that there are 76 million cleanings
annually.
     Like the amount of coating used,  it was also assumed that
the number of gun cleanings in any area of the  United States
is a  function of  it's population, estimated by the following
equation:                                             i
where :
     NUS
     Pa
     PUS
                     Na = NUS *  (Pa / PUS)
                                            (4.9)
Number of gun cleanings in area;
Number of gun cleanings in the United States;
Population of area; and
U.S. population.
     Approximately 60 percent of body shops in unregulated
nonattainment areas  of the United States use gun
cleaners.12'13  For  areas that  require gun cleaners, it was
assumed that all shops are in compliance with the
requirements.
4.3.1.1  Emissions from Gun  Cleaners
     Although gun cleaners are designed to minimize VOC
emissions, VOC evaporates during cleaning  ("active  losses"),
and, to a lesser degree, when the cleaner is not in use
("passive losses") because of brief periods of solvent
exposure to the atmosphere and  imperfect lid seals.  Active
losses are approximately 0.06 pounds per cleaning.14  The
number of cleanings  performed using gun cleaners is estimated

                              4-12

-------
by the following equation:
where:
     Nc

     Na
                         Ngc = Na *
                                                         (4.10)
               Number of  gun cleanings  performed in area using
               gun cleaners;
               Number of  gun cleanings  in area;  and
               Fraction of  shops in area that use gun cleaners.
       Gun cleaners are assumed to be in use about five percent
of the time; therefore, passive losses occur about 8320 hours
per year.  Passive losses are approximately 0.004 pounds per
hour.15  The number of shops and, thus, gun cleaners,  in a
particular area is assumed to be a function of its population.
There are approximately 50,000 body  shops in the United
States.16"18  The number of gun cleaners in .an area  is
estimated by the following equation:
                Ngun = 50,000
                                    /PUS)
                                                         (4.11)
where:
     N,
      gun
     Fa
     Pa
     PUS
               Number of gun cleaners in area;
               Fraction of shops in area that use gun cleaners;
               Population of area;  and
               U.S.  population.
     Total emissions from gun cleaners, consisting of active
and passive losses, are estimated by  the  following  equation:
        Er
               (Nac * A / 2000) +  (Naun * P * H / 2,000)   (4.12) '
                "gc
where:
     E,
     N
      gc
      gc
               "gun
Area emissions from gun cleaners  (tons/yr);
Number of gun cleanings performed in area

          4-13               .

-------
    A
    2,000
    •N,
     P
     H
gun
using gun cleaners;
Active VOC emissions (Ib/cleaning);
Pounds per ton;
Number of gun cleaners in area;
Passive VOC emissions (Ib/hr); and
Hours per year the gun cleaner is not in
use.
4.3.1.2  Emissions from Manual Gun Cleaning
     Shops  not' equipped with a gun cleaner usually rinse the
outside of the spray gun with solvent, fill the gun cup with
solvent, and then spray the solvent through the gun into a
container of spent solvent.19  The number of manual gun
cleanings performed in an area is estimated by the following
equation:
                      N,
                       !mc
                      Na  *
                 -  Fa)
(4.13)
where:
     Nmc
         Number of manual cleanings performed in area;
         Total number of gun cleanings performed in area;
         and
         Fraction of shops in area that use gun cleaners.
It was assumed that approximately 10 ounces of solvent are
used per manual gun cleaning, and that  80 percent of  the
solvent evaporates to the atmosphere.   Emissions from manual
gun cleaning were estimated by the  following equation:
            Nmc *  (10 / 128 / 2,000) * d * 0.8
                                                         (4.14)
•where:
     N,
      'me
              Area emissions  due  to manual  gun cleaning
               (tons/yr);
              Number  of manual  gun cleanings  performed in
              area;
                              4-14

-------
     10
     128
     2,000
    •d

     0.8
     Ounces per cleaning;
     Ounces per gallons;
     Pounds per ton;
     Density of solvent = 7.1 Ib/gal (850
     and
     Fraction of solvent that evaporates.
4.3.1.3  Total Gun Cleaning Emissions
     The baseline VOC emissions  for any area are the sum of
emissions from gun cleaners and manual cleaning.   (In areas
that require gun cleaners, there were assumed to be no
                 "*-_,»
emissions from manual cleaning.)  Total gun cleaning emissions
were estimated by the following equation: .     --
where:
     EC
     Lmc
          Eg —
                                  + E
                                    me
(4.15)
Total area emissions from gun cleaning
(tons/yr);
Area emissions from gun cleaners (tons/yr); and
Area emissions due to manual gun cleaning
(tons/yr).
     The above equations  were used to estimate 1995 baseline
VOC emissions from gun cleaning in nonattainment areas of the
United States.  As shown in Table 4-6, emissions were
estimated separately for each nonattainment area with an
existing regulation, and for all unregulated nonattainment
areas combined.
4.3.2  Emission Reductions from Gun Cleaning
     As  shown in Table  4-6,  nonattainment area gun cleaning
emissions would be reduced by about 55 percent by  requiring
gun cleaners.  None of these reductions are achieved in
regulated areas; emissions in unregulated areas are reduced
about 65 percent.
                              4-15

-------
TABLE 4-6.  1995 GUN CLEANING EMISSIONS AND EMISSION
     REDUCTIONS  IN NONATTAINMENT AREAS  (tons/yr)   ,
        Area
   Baseline gun
cleaning emissions
                                          Annual
                                         emission
                                        reductions
  New Jersey
  New York City
  Texas
  California
  Remaining U.S.
    nonattainment
    areas
  Total
        107
        243
         96
        280
      1,946

      2,672
   67
  152
    0
    0
1,221

1,440
                         4-16

-------
4.4  REDUCTION OF VOLATILE  ORGANIC COMPOUND EMISSIONS  USING
   '  IMPROVED  HOUSEKEEPING  PRACTICES
     The  emission reductions  achievable through improved
housekeeping practices would vary significantly from shop to
shop because of the variability in current work practices.
Nonetheless, there are common-sense measures that all shops
can adopt to reduce emissions.  Workers should take care to
minimize coatings and solvents use.  Recycling or incinerating
waste coatings and solvents at licensed waste disposal/
treatment facilities can reduce VOC emissions.  The regulating
agency can require that all shops maintain a manifest of these
wastes to ensure that they are delivered to a licensed
facility.   •.••-,.
                              4-17

-------
4.5

1.
8.
9.
10,
11,
REFERENCES
Telecon.  Forrester, J., Radian Corporation with Goulding,
B., Maaco Auto Painting and Bodyworks.   August 14, 1992.
Surface preparation product usage.

Telecon.  Forrester, J., Radian Corporation, with Dameron,
C., CBWD's Collision Repair Center.  August 10, 1992.
Surface preparation product usage.

Telecon.  Forrester, J., Radian Corporation, with
Barefoot, A., Northside Body Shop.  August 14, 1992.
Surface preparation product usage..

Telecon.  Sullivan, J., Radian Corporation, with CXNeal,
J., Tyree's Cars, Inc.  August 14, 1992.  Surface
preparation product usage.                         ;

Telecon.  Sullivan, J., Radian Corporation, with Haslip,
G., Auto Alignment.  August 14, 1992.  Surface preparation
product usage.

Meeting Summary from Sullivan, J.W., Radian Corporation,
to Schultz, K.R., E.I.  Du Pont de Nemours & Company, Inc.
July 29, 1992.  Baseline emission estimates for the
automobile refinishing industry.

Telecon. Sullivan, J.,  Radian Corporation, with Hunke,  M.,
Dawn Enterprises.  July 23, 1992.  Annual automobile
insurance statistics.
Collision Repair Industry.
1:5.  February, 1991.
Repair in the 90's.  Insight
U. S. Bureau of the Census.  Statistical Abstract  of  the
United States:  1991  (llth edition).  Washington,  DC.
1991.  p. 7.

National Paint and Coatings Association.  NPCA Automotive
Refinish Coalition's  Estimates  of  1990 National  Baseline
VOC Emissions from the Automotive  Refinish  Industry.
Washington, DC.  March 1992.

Letter from Inglis, R.,  BASF Corporation, to  Sullivan,
J.W., Radian Corporation.  March 8,  1993.   Emission
estimates for the automobile refinish industry.
12.  Telecon.  Soderberg. E., Radian Corporation with Kusz, J.,
     Safety-Kleen Corporation.  January 8, 1991.  Percent of
     refinishing shops that use Safety-Kleen spray gun
     cleaners.
                              4-18

-------
 13.  Telecon.  Campbell, D., Radian Corporation with
     Schultz, K.,  E.I. DuPont de Nemours &  Company, Inc.
     December 12,  1990.  Automobile and truck refinishing
     industry, characterization.

 14.  ENSR Consulting and Engineering.  Comparison of Solvent -
     Emissions from Two Types of Spray Gun Cleaning Systems.
     Prepared for Safety-Kleen Corporation.  Camarillo,
     California,  p. 3-2, 3-9, 3-10.

 15.  Ref. 14.

.16.  Ref. 6.

 17.  Ref. 8.

 18.  Letter from Graves, T.J., Esq., National Paints and
     Coatings Association, to South Coast Air Quality
     Management District.  July 8, 1988.  Automobile
     refinishing industry characterization and regulation.

 19.  Telecon.  Soderberg, E., Radian Corporation with Kusz, J.,
     Safety-Kleen Corporation.  January 8, 1991.
                              4-19

-------

-------
                       5.0  COST IMPACTS
     This chapter discusses the methods and assumptions used
to estimate the cost impacts of implementing the control
techniques described in Chapter 3.  Sections 5.1 and 5.2
present estimates of the costs that coating manufacturers and
distributors, respectively, would incur from the
implementation of the coating options.  Section 5.3 discusses
the costs incurred by body shops from the implementation of
the coating options, and from the use of low-VOC surface
preparation products and gun cleaners.  Cost effectiveness of
the control techniques are discussed in Section 5.4.
5.1  COSTS TO COATING MANUFACTURERS
     Coating manufacturers may incur costs from the
implementation of the VOC limits of the coating options due to
(1) process modifications,  (2) disposal of obsolete products,
and (3) training.  Research and development (R&D) costs
associated with formulating low-VOC coatings were not
considered, since these costs have generally already been
forced by State regulations.
5.1.1  Process Modifications
     Implementation of the coating options will require
manufacturers to modify production facilities.  Transition to
coatings compliant with Options 1 and 2 is estimated to cost
about $3 million.  Most of this cost would be to modify
pumping and mixing equipment to process high-solids coatings.1
Although solventborne coatings are available that meet the
primer and primer sealer VOC limits of Option 3, these limits
would likely be. met using waterborne coatings because of
difficulties in the application of high-solids coatings, such

                              5-1

-------
as the difficulty in applying a thin coat of primer sealer.
Modifications required to produce waterborne coatings, will
cost about $32 million, primarily to upgrade process equipment
from-carbon steel to corrosion resistant materials.2"5
5.1.2  Disposal Costs
     Another potential cost would be the disposal of any
coatings in body shop inventories that are made obsolete by
the control options.  There are several ways to minimize this
potential cost, including a "phase-in" period to allow for the
depletion of inventories, and redistribution of noncompliant
coatings to unregulated attainment areas.  Manufacturers were
unable to quantify the costs of redistributing noncompliant
coatings, but they-are anticipated to be small.6'7
Noncompliant coatings remaining when the phase-in period ends
may be returnable to manufacturers, who would dispose of the
coatings if another market for them could not be found.8  Due
to the phase-in period and nominal redistribution costs, it
was assumed that the costs of noncompliant coating disposal
and redistribution are insignificant.
5.1.3  Training Costs
     Implementation of the coating options would likely
require that manufacturers teach their sales representatives,
technicians/trainers, district/other managers, marketing
personnel, and "product specialists"  (personnel who provide
the interface between R&D and marketing departments) to use
the new coatings.  It was estimated that approximately
1,000 employees would require one day of training.9/10  The
cost for each was estimated at $425, including travel,
lodging, and wages.11  Training costs for all options are
assumed to be equal.
5.1.4  Annual Costs to Coating Manufacturers
     Process modification and training costs were annualized
over 10 years at an interest rate of 7 percent.  These  costs
are presented in Table 5-1.
                              5-2

-------
Table 5-1.  ANNUAL COSTS OF CONTROL TECHNIQUES
                                                      $)

Manufacturer costs
Process
modifications
Training
Distributor training
costs
Body shop costs
Surface preparation
Training
Heating systerfis.
Gun cleaners
Total annual costs
Option 1

430
60
80 .

780
240
0
(l,.230)a
360
Option 2

430
60
80

780
240
6,080
(1,230)
6,440
Option 3

4,560
60
80

780
240
6,080
(1,230)
10,570
aValues in parentheses represent costs savings or credits
                            5-3

-------
5.2  COSTS TO DISTRIBUTORS
     Coating distributors must be trained in order to provide
essential services (e.g., mixing of topcoat colors,
troubleshooting advice, general product information)  to their
customers.  An estimated 1,300 distributors would have a
representative attend a 1-day training seminar.12/13   The
total cost for each distributor was estimated to be $425,
including travel, lodging and wages.14'15
     The training costs for distributors were also annualized
over 10 years at an interest rate of 7 percent, and are
presented in Table 5-1.
5.3  COSTS TO BODY SHOPS
     Costs incurred by shops may include surface preparation
product costs, painter retraining, infrared heating system
purchase/operation, and productivity losses.  Shops would
likely incur only surface preparation product costs and
training costs if the VOC limits of Option 1 were implemented,
while Options 2 and 3 may trigger all of the costs mentioned
above.
     5.3.1  Surface preparation product costs.  Low-VOC
surface preparation products cost about $5 more per gallon
than conventional products.16  As previously discussed,  the
same amount of product is reportedly needed to prepare a
surface for refinishing; therefore, the incremental cost to
body shops for low-VOC surface preparation products is $5 per
gallon.  As shown in Table  4-3, approximately  160,000 gallons
of product are applied in nonattainment areas without VOC
limits for surface preparation products.
     As discussed in Chapter  3, low-VOC surface preparation
products may  require more time for  thorough  cleaning  and
removal than  conventional products.  Although  this additional
time could decrease shop productivity,  it  is not  expected to
be significant.
     5.3.2  Training costs.  Because  compliant coatings  may
mix, spray, and  dry differently  than  noncompliant coatings,
painters must be retrained  in these areas,   it was estimated

                              5-4

-------
that 15,150 painters will require training.  Coating
manufacturers, who will provide the training, estimate that
the requisite 8 hours of instruction17*18 can be scheduled
(during weekends or evenings) with no loss of shop
revenue, ^-^i 20
     Because training may require overtime, it was assumed
that shops will reimburse painters with overtime wages of $12
per hour  (1.5 times the normal hourly wage) and the cost of
two meals  ($15).21  It was also assumed that no travel costs
will be incurred; training will be made available locally.22"
24  The 8-hour course will be offered at no charge by coating
manufacturers..25"28   •;             .
     5.3.3  Infrared Heating System Costs.  As discussed  .
earlier,  coatings compliant with Options 2 and 3 may require
supplementary heat because their drying characteristics are
affected  by ambient conditions.  Without supplementary heating
they reportedly can require up to two days to dry.2^  TO
minimize  productivity losses, shops may purchase heating
systems to use during periods of adverse ambient conditions.
     Two  moderate-to-large heaters were assumed to be
necessary at shops.  Most shops already own one heating
system, so the costs presented in this document are for.the
purchase  and operation of an additional heating system at
15,150 shops.  Heating systems are estimated to cost $2,120
each, and are used on approximately 25 percent of refinish
jobs.30,31
     5.3.4  Spray Gun Cleaning Costs.  Costs associated with
gun cleaners include capital and maintenance costs.  Gun
cleaners  are estimated to cost $1,000 each.^2  Annual
maintenance costs include replacement parts and operating
labor, and were assumed to be 4 percent of the gun cleaner
capital cost.
     Gun  cleaners are designed to reuse cleaning solvent.   Gun
cleaners  use about 7 ounces  less solvent per cleaning than
manual cleaning, resulting in substantial  cost savings.
                              5-5

-------
     5.3.5  Potential Productivity Losses
     Coatings that meet the limits of Options 2 and 3 may
affect shop productivity because of their longer drying times.
The following is a discussion of the potential effects on
productivity of the various coatings.
          Primer surfacers.  Although a 3.8 Ib VOC/gal primer
surfacer  (Option 2) is not currently available, it is not
likely that the use of such a coating would affect shop
productivity.  The availability of a 4.05 Ib VOC/gal primer
surfacer implies that surfacers at this VOC level do not
affect shop productivity.  Further, although it may not be
perfectly suitable for.passenger car refinishing, the
currently available 2.8 Ib VOC/gal primer surfacer/sealer does
not adversely affect productivity and, in fact, may increase
productivity according to product literature-33  Since a
primer surfacer at the Option 2 limit is not currently
available, conservative estimates of annual costs for Option 2
include the purchase of infrared heating systems.
     As previously discussed, Option 3 primer surfacers are
typically based on waterborne technology.  Productivity losses
may occur in some geographical areas if these surfacers are
used.  In humid, cool conditions, waterborne surfacers are
reported to dry slowly, and drying times of up to two days
under such conditions are reportedly common  in the absence of
supplementary heating.34
     The impacts on productivity that would be caused by use
of Option 3 surfacers are highly variable and  impossible to
quantify on a nationwide basis.  For instance, a substantial
number of shops would not lose any productivity because they
would compensate for increased drying time by performing other
work while the surfacers are drying, and by  scheduling work
flow through the shop differently.  However, many shops cannot
merely work on other refinish jobs while jobs with primer
surfacer  coats are drying because  these shops  do not have
adequate  floor space.  Shops may need to use drying  equipment,
such as infrared heating systems,  to reduce  drying time.

                              5-6

-------
Shops that use infrared heating systems to accelerate drying
may still lose up to 15 minutes per job positioning the
heating systems.35  It should be noted that the use of heating
systems may not totally eliminate productivity losses.
     Primer sealers.  No productivity losses are anticipated
from the primer sealers of any option.  Shop employees in the
SCAQMD reported that primer sealers equivalent to Option 3 dry
as quickly as conventional primer sealers.36'42
     Topcoats.   Coating manufacturers report that low-VOC
topcoats dp not dry significantly slower than conventional
topcoats and, consequently, no productivity losses are
expected from the use of low-VOC topcoats.43  Manufacturers
claim, however, that shops without spray booths that use
lacquer topcoats will lose productivity when switching to
compliant topcoats.  The longer drying times of compliant
topcoats leave the wet surface exposed to airborne
contaminants.  Manufacturers maintain that shops must expend
more labor during polishing to remove the additional.
contamination.44
     Costs for shops without spray booths that use lacquers
have not been included in this document, primarily because
lacquer use for automobile refinishing has steadily dropped
over the last few years, a trend which would likely continue
even in the absence regulatory action.  In 1988 and 1993,
lacquers were used on 25 percent and 14 percent of refinish
jobs, respectively.45/46  Furthermore, there is evidence that
most shops without spray booths are already using conventional
enamels or urethanes, which, as mentioned previously, do not
dry significantly faster than low-VOC topcoats.
     5.3.6  Annual Costs to Shops
     The capital costs of heating systems and gun cleaners,
and the costs of training were annualized over 10 years at an
interest rate of 7 percent.  These annualized costs, annual
costs of electricity and maintenance of heating systems,
annual gun cleaner maintenance costs, and annual costs of low-
VOC surface preparation products are presented in Table 5-1.

                              5-7

-------
5.4  COST EFFECTIVENESS
     Average cost effectiveness is the cost to reduce VOC
emissions by 1 ton.  Average cost effectiveness values were
calculated by dividing annual costs by annual emission
reductions.  Although surface preparation and gun cleaner
costs are presented with the coating options in Table 5-1,
these control techniques could be implemented separately;
therefore, the cost effectiveness of these techniques are
described individually.
     VOC reductions from the use of low-VOC surface
preparation products cost about $2100 per ton.  Although there
are annual capital recovery and maintenance costs associated
with using gun cleaners, the savings achieved from the use of
less solvent results in a credit of about $900 per ton of VOC
emission reductions.
     The annual costs of the coating options include costs for
process modifications, manufacturer, distributor, and body
shop training, and infrared heating systems  (Options 2 and 3).
The average cost effectiveness of Options 1 through 3 are $80,
$600, and $900 per ton, respectively.
     Incremental cost effectiveness is the cost to achieve the
incremental emission reductions from implementing one option
instead of another.  The cost for the additional emission
reductions achieved by Option 2 over Option 1 is about $8,000
per ton.  The incremental cost effectiveness of implementing
Option 3  (instead of Option 2) is about $5,000 per ton.
                              5-8

-------
5.5  REFERENCES

1,   Telecon.  Sullivan, J. W.,  Radian Corporation, with
     Schultz, K. R.,  E.I. du Pont de Nemours & Company, Inc.
     March 16, 1993.   Costs of regulation.

2.   Ref..1.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Meeting Summary from Sullivan, J. W.,  Radian Corporation,
to Sell, J., National Paint and Coatings Association, et.
al.  January 8, 1993.  National Paint and Coatings
Association Automotive Refinish Coalition views on future
Federal regulation.

Letter from Schultz, K. R., E.I. du Pont de Nemours &
Company,.Inc., to Sullivan, J. W., Radian Corporation.
June 18, 1993.  Cost estimates of plant modifications
necessary to produce waterborne coatings.

Sullivan, J. W.,  Radian Corporation.  September 13, 1993.
Calculation of costs to manufacture waterborne primers.

Telecon.  Burk, D. G.,  Radian Corporation, with Inglis,
R., BASF, Inc.  June 2, 1993.  Effects of regulation on
inventory distribution and coating waste handling and
disposal cost.

Telecon.  Burk, D. G.>  Radian Corporation, with
Sieradzki> R., AKZO, Inc.  June 3, 1993.  Effects of
regulation on inventory distribution and coating waste
handling and disposal cost.

Telecon.  Sullivan, J.  W., Radian Corporation, with
Schultz, K: R., E.I. du Pont de Nemours & Company, Inc.
April 9, 1993.  Impacts of regulation.

Meeting Summary from Sullivan, J. W.,  Radian Corporation,
to Sell, J., National Paint and Coatings Association, et.
al.  Model shops and costs of Federal regulation.
July 9, 1993.

Memorandum and attachments from Sullivan, J. W., Radian
Corporation, to Radian Project File.  August 31, 1993.
Training and low-VOC coatings.
Letter from Sell, J., National Paint and Coatings
Association, to Ducey, E., EPA/CPB.  June 3, 1993.
of Federal regulation.
                                                         Costs
                              5-9

-------
12
13.



14,

15.

16,

17,

18,

19,

20,
21.

22.

23.

24.

25.

26.

27.

28.



29,
Letter from Roland, D. R., Automotive Service Industry
Association, to Ducey, E., EPA/CPB.  January 22, 1993.
Comments on chapters 4 and 5 of draft Automobile
Refinishing CTG.

Sullivan, J. W., Radian Corporation, September 13, 1993
Calculation of manufacturer and distributor training
costs.

Ref. 10.

Ref. 11.
Ref.

Ref,

Ref.

Ref,
1.

10.

11.

10.
Letter from Carragher, R. J., Automotive Service  Industry
Association, to Ducey E., EPA/CPB.  May 10, 1993.
Comments on training for the automotive refinishing
industry rulemaking.

Ref. 20.

Ref. 10.

Ref. 11.

Ref. 20.

Ref. 9.

Ref. 10.

Ref. 20.

Telecon.  Burk, D. G., Radian Corporation,  with
Sieradzki, R., AKZO Coatings, Inc.  March  25,  1993.
Painter retraining.

Memorandum from Sell, J., National  Paint and  Coatings
Association, to Sullivan, J. W.,  Radian Corporation.
August 23, 1993.  Additional background information
concerning the Automotive Refinish  Background Information
Document.
                              5-10

-------
30.  Telecon.  Sullivan, J. W.,  Radian Corporation, with
     Gregory, D.  April 1, 1993.  Edwin Trisk heating lamps.

31.  Telecon.  Sullivan, J. W.,Radian Corporation, with
    . Hutchins, J.  March 22, 199.3.  Infratech curing systems.

32.  Ref. 9.

33.  PPG Industries.  Product Bulletin No. 184. December,
     1993.

34.  Ref. 29.

35.  Ref. 29.

36.  Sullivan, J. W.,  Radian Corporation.  Site visit at R. B.
    . Paint and Body Center.  Sante Fe Springs, CA.  prepared
     for Morris, M. , EPA/CPB.  August 25, 1993.

37.  Sullivan, J. W.,  Radian Corporation.  Site visit at One
     Day Paint and Body, Anaheim, CA.  Prepared for Morris,
     M. ,  EPA/CPB.  August 25, 1993.

38.  Sullivan, J. W.,  Radian Corporation.  Site visit at Lee's
     Body Works.  Sante Fe Springs, CA.  Prepared for Morris,
     M.,  EPA/CPB.  August 25, 1993.

39.  Sullivan, J. W.,  Radian Corporation.  Site visit at Maaco
     Auto Painting.  Sante Fe Springs, CA.  Prepared for
     Morris, M., EPA/CPB.  August 25, 1993.

40.  Sullivan J. W., Radian Corporation.  Site visit at House
     of Imports.  Buena Park, CA.  Prepared for Morris, M.,
     EPA/CPB.  August 25, 1993.

41.  Sullivan, J. W.,  Radian Corporation.  Site visit at
     Camenita Collision Center.   Sante Fe Springs, CA.
     Prepared for Morris, M., EPA/CPB.  August 25, 1993.

42.  Sullivan, J. W.,  Radian Corporation.  Site visit at Dave
     Salas Metric's Auto Body Shop.  Sante Fe Springs, CA.
     August 25, 1993.

43.  Ref. 9

44.  Ref. 9

45.  Body Shop Business.  1990 Annual Industry Profile.  9_:49.
     June 1990.

46.  Babcox Publications.  1993 Annual Industry Profile.
     p. 48.  June 1993.
                              5-11

-------

1. REPORT NO.
EPA-453/R-94-031
TECHNICAL REPORT DATA
(Please read Instructions on reverse before completing)
2.
4. TITLE AND SUBTITLE
Alternative Control Techniques Document:
Automobile Refinishing
7.AUTHOR(S)
9. PERFORMING ORGANIZATION NAME AND ADDRESS
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Technical Support Division
Research Triangle Park, NC 27711
12. SPONSORING AGENCY NAME AND ADDRESS '' " :
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Technical Support Division
Research Triangle Park, NC 27711
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
April 1994
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
13. TYPE OF REPORT AND PERIOD COVERED
Final
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This document provides information on alternative control techniques (ACT) for volatile organic
compound (VOC) emissions from automobile refinishing. This document contains information on
emissions, controls, control options, and costs that States can use in developing rules. The document
presents options only, and makes no recommendations.
17.
». DESCRIPTORS
KEY WORDS AND DOCUMENT ANALYSIS
b. IDENTIFIERS/OPEN ENDED TERMS
Air Pollution
Volatile Organic Compounds
Automobile Refinishing
Alternative Control Techniques
IS. DISTRIBUTION STATEMENT
Release Unlimited
19. SECURITY CLASS (Report)
Unclassified
20. SECURITY CLASS (Page)
Unclassified

c. COSATI Field/Group

21. NO. OF PAGES
80
22. PRICE
EPA Fona 2220-1 (Rev. 4-77)    PREVIOUS EDITION IS OBSOLETE

-------