United States
                   Environmental Protection
                   Agency
Air and Energy Engineering
Research Laboratory
Research Triangle Park NC 27711
                   Research and Development
EPA/600/S2-88/061 Jan. 1989
&EPA          Project Summary
                    Evaluation  of  Perchloroethylene
                    Emissions from Dry Cleaned
                    Fabrics

                    Bruce A. Tichenor, Leslie E. Sparks, and Merrill D. Jackson
                      A  study  was  conducted  to
                   evaluate  the  emissions   of
                   perchloroethylene (perc)  from  dry
                   cleaned fabrics to determine: a) how
                   the introduction of fresh dry cleaning
                   Into a  home affects the  indoor
                   concentration of perc, and  b)  the
                   effectiveness of "airing  out"  for
                   reducing perc emissions.  Small
                   chamber tests were  conducted to
                   determine perc  emission charac-
                   teristics for three fabrics at  several
                   temperatures and air exchange rates.
                   Test house studies  were conducted
                   to  determine the indoor concen-
                   tration of perc due to the placement
                   of dry cleaned clothing in the house.
                   Based on the study results, and
                   assuming the test conditions were
                   representative of normal dry cleaning
                   and consumer practices, it is con-
                   cluded that
                    1) Emissions  from freshly  dry
                      cleaned clothing cause elevated
                      levels of  perchloroethylene in
                      residences, and
                    2) For the three  fabrics tested,
                      "airing out" of  dry  cleaned
                      clothing by consumers will  not
                      be  effective   In  reducing
                      perchloroethylene emissions.
                   Significant variations in dry cleaning
                   practices and/or in the mix of fabrics
                   and clothing  being  cleaned could
                   provide different  results  and
                   conclusions.
                      This Project Summary  was
                   developed by  EPA's Air and  Energy
                   Engineering Research Laboratory,
                   Research  Triangle  Park NC,  to
                   announce  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).

 Introduction
   The  EPA's Air and Energy  Engin-
 eering  Research Laboratory  (EPA/
 AEERL) conducted a short term study to
 evaluate the emissions  of perchloro-
 ethylene (perc) from dry cleaned fabrics.
 Specifically, the study was designed to
 answer two questions:
  •To what extent does the residual perc
   in dry cleaned fabric increase the
   concentration  of perc in residential
   environments?
  •How effective  is  "airing  out" in
   reducing indoor perc concentrations?
   A study consisting of five components
 was conducted:  1) Fabric/Clothing  Se-
 lection; 2) Emission Factor Determination
 (Small Chamber Testing); 3) Evaluation
 of Perc  Residuals  (Solvent Extraction); 4)
 Indoor Air Quality (IAQ) Model Analysis;
 and 5) Evaluation of Indoor  Concen-
 trations (Test House).

 Results

 Emission Factors
   Emission factors for perchloroethylene
 from  dry  cleaned fabrics  were
 determined  by  testing in  small
 environmental  test  chambers  under
 controlled conditions.   Evaluation of the
 data from these tests provided several
 conclusions:
 - A preliminary  screening evaluation
   showed that wide  variations in initial
   emission factor, Ro,  and  emission
   factor half-lives,  t(1/2),  occurred
   between  different fabrics.  Thus, the

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  type  of  fabric  is  important  in
  determining indoor emissions of perc
  from dry cleaned clothes.
  Based on the screening study and on
  the  prevalence of fabrics used in dry
  cleaned clothing, three fabrics  were
  selected  for  investigation:  55%
  polyester/45% wool;  100% wool; and
  50%polyester/50% rayon.
  The air  exchange rate showed no
  effect on the emission factor or decay
  rate for the three fabrics investigated.
  This suggests that the emissions are
  limited by the diffusion of perc  within
  the  fabric  and  are not  controlled by
  evaporative processes.  This  also
  suggests  that increasing the ventila-
  tion by airing out the clothes will not
  speed up the emission of perc.

  Since  the  three  fabrics tested had
  emission  factor  half-lives  of about a
  day, airing the clothes out for  a few
  hours  before  hanging  them in the
  home will do little to reduce the indoor
  perc concentrations.  For fabrics with
  faster  perc decay rates, airing out
  may be more practical.
         -  Temperature had a major impact on
            the emission factors and decay rates.
            Increases in temperature  caused
            higher  initial emission factors and
            lower half-lives.   Thus, exposing  the
            clothing to higher temperatures prior
            to bringing them home shows promise
            as a means of  reducing in-home
            exposure to perc.

         Residuals
            No acceptable data  were developed
         on the perc residuals within the fabric.
         The  solvent  extraction procedure, using
         methylene chloride,  failed  to  produce
         reliable results.  A fully tested "standard
         method" is needed.


         Indoor Concentrations
            All the test house  experiments
         showed that the introduction  of dry
         cleaned  clothing caused elevated  levels
         of perc  in the  house.   Differences  in
         concentration between  the  tests were
         probably  due  to  differences  in the
         amount  of perc  retained  at  the dry
         cleaner.
   Bruce A. Tichenor, Leslie E. Sparks, and Merrill D. Jackson are with EPA's Air
        and Energy Engineering Research Laboratory, Research Triangle Park,
        NC 27711.
   Bruce A. Tichenor is the EPA Project Officer (see below).
   The complete report, entitled "Evaluation of Perchloroethylene Emissions from
        Dry Cleaned Fabrics," (Order No. PB  89-118  681/AS;  Cost:  $15.95,
        sub/'ect 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:
            Air and Energy Engineering Research Laboratory
            U.S. Environmental Protection Agency
            Research Triangle Park, NC 27711
Model Results
   The IAQ model, using emissions d
developed  in  the  small  chambe
predicted indoor  perc  concentratio
which compared favorably  with the
measured in the test house.  The effi
of perc "sinks" in the test house was al
demonstrated.

Conclusions
   Based  on the  study results, a
assuming the  test conditions  a
representative of normal dry cleaning a
consumer practices, it is concluded tha
   1)    Emissions from freshly  d
cleaned clothing  cause elevated levels
perchloroethylene in residences.
   2)    For the three  fabrics  teste
"airing out of dry cleaned  clothing
consumers is not  effective  in reduci
perchloroethylene emissions."
   It  is  emphasized  that  the
conclusions are  based on the  results
the study reported  herein. Signifies
variations in dry cleaning practices and<
in the mix of fabrics and clothing bei
cleaned could provide different  resu
and conclusions.
United States
Environmental Protection
Agency
Center for Environmental Research
Information
Cincinnati OH 45268
                                                                                          riff is o .2 s; •
Official Business
Penalty for Private Use $300

EPA/600/S2-88/061
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