United States
                  Environmental Protection
                  Agency
Atmospheric Research and     ~ A
Exposure Assessment Laboratory  **
Research Triangle Park NC 27711   '>
                  Research and Development
EPA/600/S3-89/040 Sept. 1989
&EPA         Project Summary
                  Characterization  of Painted
                  Surfaces in the  United States
                  from the  Perspective of
                  Potential  Damage from Acidic
                  Deposition
                  Frederick W. Lipfert
                    Data are reviewed on the  types
                  and applications of exterior paints
                  used in the United States, from the
                  perspective of potential damage by
                  air pollution or acidic deposition.
                  Residential buildings are the most
                  economically important subset of the
                  painted structures in the  United
                  States for painting costs; this ranking
                  is likely to continue in the  future.
                  Painting over existing finishes is an
                  important class of situations for re-
                  search, because these conditions are
                  more common and more difficult than
                  virgin surfaces. Automobile finishes
                  are a high-value use of paint, but the
                  importance of acid deposition as a
                  reason  to repaint  has  not  been
                  established.
                    Based on consumer surveys, the
                  most important mode of paint failure
                  is peeling, which accounts for about
                  half of residential paint problems.
                  Such problems, often  occur witWn
                  two to three years after painting;.
                  Color changes (deterioration^ are
                  next in importance,  followed by
                  chalking and erosion. Painting  solely
                  to change color or to aid in the resale
                  of  the property  is of minor im-
                  portance. Paints  containing  acid-
                  sensitive components, especially oil-
                  based glossy paints, may be found in
                  today's  retail market  in all  price
                  ranges. Trends  in paint usage and
                  performance are generally supportive
of (or  not inconsistent with) the
hypothesis that air pollution or acid
rain may be  having some adverse
effects, although such data are by no
means conclusive. The report recom-
mends  that selections of coatings
and substrates for  acid deposition
research should include those com-
binations that are widely used (latex
over wood and over previous  paint)
and those that are sensitive to acid
deposition (paints containing CaCO3;
alkyd paint over steel).
  This  Project Summary was devel-
oped by EPA's Atmospheric Research
and Exposure  Assessment Laboratory,
Research Triangle Park, NC,  to an-
nounce key findings of the research
project  that is fully documented in a
separate report of the same title (see
Project Report ordering information at
back).

fntroduction
  The National Acid Precipitation As-
sessment Program (NAPAP) is responsi-
ble for developing an understanding of
the causes and effects  of acidic dep-
osition and for  supporting decision-
making on strategies to reduce acid dep-
osition. Damage to structural materials is
an important component,  since the po-
tential economic effects are large by vir-
tue of the many structures exposed to
acid deposition. The U.S. Environmental
Protection Agency conducts research on

-------
acid deposition damage to common con-
struction materials, which include metals
and  painted surfaces. This research pro-
vides guidance to the EPA research pro-
gram on the mechanisms of damage to
painted surfaces by acid deposition.

Results and Discussion
   Data on the types and applications of
exterior paints used in the United States
were reviewed from the perspective of
potential  damage by air  pollution  or
acidic deposition. Sources of information
included data from the Census of Manu-
factures  on factory  shipments  of paint
and allied products, statistics on the con-
struction industry, data on consumer ex-
penditures for residential  repairs and
alterations, and data from consumer sur-
veys. This information shows that  resi-
dential  buildings  are the  most eco-
nomically important subset of the painted
structures in  the United States  in  terms
of the  costs of painting. The trends for
new  construction suggest that this rank-
ing is likely to continue in the future.
   Table  1  presents  preliminary data
from the  1987 Census of Manufactures
including shipment volumes  (million gal-
lons), factory values (million dollars), and
m-place values which  include estimated
mark-ups  and  application labor (billion
dollars), for outdoor paint  applications.
The  annual  in-place  value of  archi-
tectural coatings is the highest category,
followed by automotive (and other trans-
portation equipment) paints. Maintenance
paints, coil coatings, and traffic marking
paints  have substantially lower in-place
values.  The ranking  of automotive fin-
ishes must be discounted because of the
high  proportion of painting done to repair
body damage, rather  than  because  of

                                Table 1.
paint failure. Considering that a car may
be ten or more years old by the time its
refinished paint nears failure, extending
the life of this paint would appear to have
only  marginal  value  relative to the re-
maining value of the car. In addition, the
importance of acid deposition as a cause
of failure  of automotive finishes has not
been established.
   To gain insight  into the uses of archi-
tectural coatings,  estimates were  made
for new construction,  maintenance paint-
ing, residential maintenance, and painting
costs for various  other types  of  struc-
tures, based on published data.  The es-
timate for 1977 for  residential painting,
including  the  estimated  value  of  do-it-
yourself labor, was about $14 billion;  by
1986, the estimated value had  risen to
about $20-30  billion. A  1977  input-
output analysis of the US construction in-
dustry estimated that $147 million was
spent for maintenance painting costs to
non-buildings and  $1 1 billion for  build-
ings,  which confirmed the  relatively low
rank of maintenance painting. In addition,
the 1979  national  expenditure for corro-
sion protection of  highway  bridges was
estimated  at  $130-160  million  (which
was  about half of  what was needed for
adequate corrosion  protection).  Even
after  accounting for inflation,  this cate-
gory  would not rank  high  in Table  1.
However,  the costs of bridge failure due
to inadequate maintenance  have  not
been  considered;  a  1984  estimate  of
spending  on  new  and  rehabilitated
bridges  excluding  maintenance  was
about $5 billion.
   According  to several  consumer sur-
veys, the most important mode  of paint
failure appears to be peeling and flaking,
which, in  its various manifestations,

  7987 Paint Shipments and Associated Costs
  (exterior uses)
accounts  for about  half  of  resident!
paint problems. Figure 1 shows the  di
tribution of  reasons for repainting give
by respondents to a large  mail  survey
1975.  This  survey and others  indica
that  such problems often occur within tv\
to three years  after application, althouc
manufacturers' test panel results seldoi
identify peeling as  an  important mode <
paint film failure. Based on several  su
veys,  color  changes  (deterioratioi
ranked next  in importance.  Althoug
chalking and  erosion have  been  ol
served, their roles in decisions to repai
are  less  apparent. Painting  solely 1
change color or for resale of the proper
appears to be of minor importance.
   In Figure 2, the 1975 consumer surve
data have  been segregated by Censt
Region and according to whether or m
there was prior peeling, which  is seen I
have a major influence on the percentag
of respondents with  new  paint peelini
The  West region had the fewest peeliri
problems. The  probability of new peelin
was  increased  by about a  factor of thre
if peeling had occurred previously, in s
regions and  for  all types  of  paint.  Th
performance of a given type of paint  wa
dependent  on  the type  of paint alread
on the  surface. In the absence of pr«
vious peeling, latex paint applied over a
oil-based  paint was usually  the mo;
likely to peel,  especially  in  the  Nort
Central or Northeast Regions.  With pre
vious  peeling,  the  differences  wer
smaller but latex over latex was often th
worst,  suggesting that a deteriorated oi
based  paint  surface may  provide  bette
adhesion for repainting.
  Although  the Northeast  and Nort
Central Regions rank  highest  in  aci
deposition  and  had  the poorest pair
                                                Shipments  Factory Cost In-place Value
                                Classification     million gal.    million $      billion $
                               Architectural Coatings (exterior)
                                  Oil-based          80        $807
                                  Water-based      123         944

                               Automotive Finishes
                                  new vehicles       73        1323
                                  refimshing         44         904

                               Coil Coating           20         303

                               Industrial Main-
                                  tenance Paints      28         313

                               Traffic Marking
                                  Paints             19          95
                                 $9.5
                                  14.6
                                   6.0
                                  11.0

                                   2.0


                                   2.8


                                   0.7

-------
                                            Reasons for repainting
                                               1975 mail survey
                                  Other (5.8%)

                 Unpainted sfc (4.5%)
                                                            Erosion (17.4%)
   To change color (8.6%)
       Dirt (9.9%)
      Mildew (2.8%)



   Orig. color chg (5.1%)
Figure 1.
Distribution of reasons for repainting (1975 mail survey).

-------
                                                    2                 3

                                                    Years since repainting
         Figure 2.     Percent of respondents with paint peeling or flaking (1975 mail survey).
performance, there  are  many other  re-
gional environmental differences to con-
sider  besides  acid  deposition in  evalu-
ating  differences  in  paint performance.
For example, the North Central  Region
surfers more from weather extremes be-
cause of its continental climate; also the
winter ultraviolet radiation exposure of a
vertical  wall may be  higher in more
northern latitudes because of the low sun
angles and reflection from snow covered
ground  surfaces.  Nevertheless,  the
trends in  paint usage and  performance
are generally supportive of  (or at least
not inconsistent with) the hypothesis that
air  pollution or  acid   rain  may   be
manifesting  some adverse  effects, al-
though  such  data are  by no means
conclusive.
   Not all paint formulations are expected
to be sensitive to acid deposition. Previ-
ously it was thought  that the cheapest
paints might be the most sensitive, but
acid-sensitive paint  components  may
be found  in today's retail market m all
price ranges, especially in  oil-based
glossy paints. These components include
calcium carbonate (CaCOj), which is an
inexpensive  pigment  used an  extender
(thickener), and zinc oxide (ZnO), which
is used  as a pigment  and in conjunction
with mildewcides.
Recommendations

   The  report recommends  that  selec
lions  of coatings and  substrates for re
search on the effects  of acid depositioi
should include both those combination
that  are most  widely  used  (latex ove
wood and over previous paint) and thosi
that  are sensitive to acid  depositioi
(paints  containing  CaCOa, alkyd  pain
over steel)  Although both new construe
tion and maintenance  painting are eco
nomically  important, the  more difficul
conditions involved  in painting over exist
mg finishes make this an important clas:
of situations for research.

-------
  Frederick W. Lipfert is with Brookhaven National Laboratory, Upton, NY 11973
  J. W. Spence is the EPA Project Officer (see below).
  D. £ Renard is the Army Project Officer (see below).
  The complete report, entitled "Characterization of Painted Surfaces in the United
        States from the Perspective of Potential Damage from Acidic Deposition,"
        (Order No.  PB 89-181 2261 AS; Cost: $15.95, subject  to change)  will be
        available only from:
           National Technical Information Service
           5285 Port Royal Road
           Springfield, VA 22161
           Telephone: 703-487-4650
  The EPA Project Officer can be contacted at:
           Atmospheric Research and Exposure Assessment Laboratory
           U.S. Environmental Protection Agency
           Research Triangle Park NC 27711
United States                   Center for Environmental Research
Environmental Protection         Information
Agency                         Cincinnati OH 45268
Official Business
Penalty for Private Use $300

EPA/600/S3-89/040
        000085833   PS

-------