oEPA
           United
           Environmental Protection
           Agency
               Office of
               Toxic Substances
               Washington D.C.
EPA 560/5-88-007
March 1990
           Office of Toxic Substances
ASBESTOS CONTAINING THERMAL
SYSTEM INSULATION:  FACTS AND
FIGURES

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                                        EPA 560/5-88-007
                                             March,  1990
                 FINAL REPORT
ASBESTOS-CONTAINING THERMAL SYSTEM INSULATION:
               FACTS AND FIGURES
                 Prepared by:

           Chesson Consulting, Inc.
         1717  Massachusetts  Ave.,  N.W.
             Washington, DC 20036
                   Battelle
               Arlington Office
       2101 Wilson Boulevard, Suite 800
             Arlington, VA  22201

            Contract  No.  68-02-4294
                   for the:

         Exposure Evaluation Division
          Office of Toxic Substances
   Office of Pesticides and Toxic Substances
     U.S. Environmental Protection Agency
             Washington, DC 20460

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This document has been reviewed and approved for publication by
the Office Of Toxic Substances, Office of Pesticides and Toxic
Substances, U.S. Environmental Protection Agency.  The use of
trade names or commercial products does not constitute Agency
endorsement or recommendation for use.

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                    AUTHORS AND CONTRIBUTORS

This report was prepared by Jean Chesson of Chesson Consulting,
Inc. under contract to Battelle.   Amy Doll and David Lawrence of
Chesson Consulting prepared the illustrations.  Mark Wright,
under contract to Battelle, designed the cover.

The EPA Work Assignment Manager was Bradley Schultz.  Substantial
contributions were also made by Cindy Stroup,  Betsy Dutrow, and
Joe Breen of the Exposure Evaluation Division in the EPA Office
of Toxic Substances.

                         ACKNOWLEDGMENTS

Al Unger and Barbara Leczynski, the Battelle Project Managers,
and Edie Sterrett and Mary Frankenberry, the EPA Project
Officers, provided managerial and administrative support.
Discussions with John Rogers of Westat, Inc. were invaluable in
interpreting the EPA survey data.
                               iii

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                        TABLE OF CONTENTS
SUMMARY	   Vll

1.  INTRODUCTION  	    1
     1.1  DESCRIPTION OF ASBESTOS-CONTAINING THERMAL SYSTEM
          INSULATION  	    1
     1.2  FEDERAL REGULATORY PROGRAMS 	    2

2. CHARACTERISTICS OF ASBESTOS-CONTAINING
                    THERMAL SYSTEM INSULATION 	    3
     2.1  PREVALENCE	    3
          Building Type	    5
          Building Age	    7
          Building Height	    7
          Geographical Region	    8
     2.2  ASBESTOS CONTENT  	    8
     2.3  CONDITION	     10
          Building Type	     10
          Building Age	     10
          Building Height	     11
     2.4  LOCATION	     15
     2.5  AIRBORNE ASBESTOS LEVELS   	     16

3.  MANAGING ASBESTOS-CONTAINING THERMAL SYSTEM INSULATION      21
     3.1  DETERMINING IF ASBESTOS-CONTAINING MATERIAL  IS
          PRESENT IN A BUILDING	     21
     3.2  ESTABLISHING AN OPERATIONS AND MAINTENANCE
          PROGRAM	     22
     3.3  ASSESSING THE NEED FOR FURTHER ACTION	     22
     3.4  IMPLEMENTING RESPONSE ACTIONS 	     22

REFERENCES	     25

APPENDIX A.  EPA REGIONAL ASBESTOS COORDINATORS 	     29

APPENDIX B.  SOURCES OF ADDITIONAL INFORMATION  	     33
                                IV

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                         LIST OF FIGURES
Figure 1.  The estimated number of buildings (in thousands) with
asbestos-containing materials	   4

Figure 2.  The relationship between type of building and type of
ACM; a) estimated number of buildings,  b)  estimated percent of
buildings, c) estimated total floor area	   6

Figure 3.  The relationship between building construction date
and presence of asbestos-containing material	   7

Figure 4.  The relationship between building height and type of
ACM; a) estimated number of buildings,  b)  estimated percent of
buildings, c) estimated total floor area	   9

Figure 5.  The number of buildings (in thousands) that have no
asbestos-containing TSI, TSI with no damage, TSI with some
moderate damage only, and TSI with some significant damage.    11

Figure 6.  The relationship between type of building and
condition of asbestos-containing TSI; a) estimated number of
buildings in each condition category, b) estimated percent of
buildings, c) estimated total floor area	    12

Figure 7.  The relationship between building construction date
and condition of asbestos-containing TSI; a) estimated number of
buildings in each condition category, b) estimated percent of
buildings, c) estimated total floor area	    13

Figure 8.  The relationship between building height and condition
of asbestos-containing TSI; a) estimated number of buildings in
each condition category, b) estimated percent of buildings, c)
estimated total floor area	    14

Figure 9.  The estimated number of buildings (in thousands) with
asbestos-containing material in fan and boiler rooms and in
public areas	    16

Figure 10.  In EPA's study of public buildings  (USEPA 1988),
average airborne asbestos  levels in 15 buildings with only TSI
followed a similar trend to that observed in all 49 buildings. 18
                                VI

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                             SUMMARY


           Thermal  system  insulation  (TSI) is material applied to
 pipes,  boilers,  tanks, ducts, etc. to prevent heat loss, heat
 gain,  or water condensation.  TSI that contains asbestos
 represents a potential health hazard to custodial and maintenance
 personnel  working  with and around the material.  However,
 compared to other  types of building materials that contain
 asbestos,  TSI is often easier to repair, encapsulate, enclose, or
 remove.  This document provides information on the
 characteristics  of asbestos-containing TSI and lists resources
 available  to individuals  who are responsible for making asbestos
 management decisions.

           The purpose of  this report is to draw attention to
 asbestos-containing TSI without diminishing the importance of
 other  types of asbestos-containing material.  Information on the
 characteristics  of asbestos-containing TSI is provided.  Research
 on asbestos and  guidance  on its management have tended to
 emphasize  surfacing material at the expense of TSI.  While each
 building must be individually and thoroughly inspected for all
 types  of asbestos-containing materials by a qualified building
 inspector,  the information contained in this report will help
 building owners  and managers, especially those responsible for
 large  numbers of buildings, anticipate possible outcomes and plan
 appropriate actions.  Although this document is not an
 instruction manual for inspecting buildings for asbestos-
 containing material, or for the management or specific abatement
 of these materials, a brief overview is provided to help readers
 identify sources of additional information.

           In 1984,  the U.S. Environmental Protection Agency
 conducted  a national survey to determine how many buildings
 contain asbestos (USEPA 1984).  The survey found that of the
 approximately 3.6  million buildings represented in the survey,
 about  733,000 contain some type of asbestos material.  The most
 common  forms of  asbestos-containing material are thermal system
 insulation as described above, and sprayed- or trowelled-on
 surfacing  material.  Of the 733,000 buildings estimated to
 contain asbestos,  most (about 563,000) have asbestos-containing
 TSI.  Many fewer (about 192,000 buildings) have asbestos-
 containing surfacing material.  (A small number of buildings have
 both asbestos-containing  TSI and surfacing material.)

           The EPA  Survey  showed that TSI is more likely to be
 present in some  types of  building than in others.  Of the
building categories covered by the survey, residential apartment
buildings,  buildings built prior to 1944, and buildings of 8
 floors or  njpre are most likely to have asbestos-containing TSI.
This does  not mean, of course, that all buildings in these
categories  have  asbestos-containing TSI.

                               vii

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          Asbestos fibers are believed to be released from TSI
through disturbance of the material.   Visible damage indicates
that disturbance has occurred.  The EPA Survey found that over
half the buildings with asbestos-containing TSI have some
significantly damaged TSI and 80 percent have at least some
damaged TSI.  TSI is more likely to be damaged in commercial non-
residential buildings, in buildings constructed prior to 1944,
and in buildings of 8 floors or more.

          Although TSI is typically associated with restricted
areas such as fan and boiler rooms, a  substantial number of
buildings (at least 262,000) have asbestos-containing TSI in
public areas.  For instance, a pipe wrapped with asbestos-
containing TSI may run through office  space.  Limited information
indicates that elevated airborne asbestos concentrations can
occur during disturbance of the material.

          Results from a recent study  of asbestos in New York
City are in general agreement with the EPA findings (NYCDEP
1988).  Overall, asbestos-containing TSI is more prevalent than
asbestos-containing surfacing material, and more of the TSI is in
poor condition.  However, surfacing material is more prevalent in
some types of New York City buildings, especially tall office
buildings, hospitals, and theaters and places of public assembly.

          Since asbestos is restricted to TSI in many buildings,
the majority of asbestos control programs will not have to
address asbestos-containing surfacing  material.  TSI is generally
easier and less costly to repair, remove or replace.  EPA
recommends that building owners and managers obtain proper
training for their staff or hire specialists to inspect their
buildings and develop asbestos management plans.   (Under the
Asbestos Hazard Emergency Response Act of 1986, this is mandatory
for schools.)  A building owner or manager's approach to
controlling asbestos-containing material will generally involve
four basic steps.  First, determine if asbestos-containing
material is present.  Second, establish a special  operations  and
maintenance plan.  Third, assess the need for further action.
Finally, take further action as appropriate.  Documents produced
by EPA and other organizations provide guidance on implementing
each step.
                               Vlll

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IX

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                         1.  INTRODUCTION


          Thermal system insulation (TSI)  is material .applied to
pipes, boilers, tanks, ducts,  etc.  to prevent heat loss, heat
gain, or water condensation.   Asbestos-containing TSI represents
a potential health hazard,  particularly to custodial and
maintenance personnel working with and around the material.  In
February 1988, in response  to the findings of a study mandated
by the 1986 Asbestos Hazard Emergency Response Act (AHERA), the
Administrator of the U.S. Environmental Protection Agency (EPA)
recommended that attention  be focused on asbestos-containing TSI.
This recommendation was made because much is known about the
identification and control  of asbestos-containing TSI and,
compared to other types of  asbestos materials, TSI is often
easier to repair, encapsulate, enclose or remove.

          This document provides information on the
characteristics of asbestos-containing TSI and lists resources
available to individuals responsible for making asbestos
management decisions.  This document is not an instruction manual
for inspecting buildings for asbestos-containing TSI, or for the
management or specific abatement of these materials.  EPA
recommends that building owners and managers obtain proper
training for their staff or hire specialists to inspect their
buildings and develop asbestos management plans.  (Under AHERA
this is mandatory for schools.)  Appendix A contains a list of
the EPA Regional Asbestos Coordinators who may be contacted for
information on approved training courses and other asbestos
related matters.  Additional reference sources are given in
Appendix B.

1.1  DESCRIPTION OF ASBESTOS-CONTAINING THERMAL SYSTEM INSULATION

          Asbestos-containing TSI is typically found on equipment
containing hot or cold air or liquid — pipes, boilers, chillers,
tanks, and sometimes ducts.  The insulation may be a chalky
mixture of magnesia and asbestos, preformed fibrous asbestos
wrapping, asbestos fiber felt, corrugated paper, or insulating
cement, and is usually covered with a protective jacket of cloth,
tape, paper, metal, or cement.  Boiler insulation may consist of
thermal bricks  (refractory) or asbestos insulating blankets, and
is usually covered with finishing cement.  Occasionally, asbestos
millboard is used as a stiff outside covering on removable boiler
insulation.

The data described in this report refer to asbestos-containing
TSI located within buildings.  Asbestos-containing TSI may also
     IMEPA Study of Asbestos-Containing Materials in Public
Buildings: A Report to Congress."  U.S. Environmental Protection
Agency, Washington, D.C.  February, 1988.

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 be found on utility systems  serving groups  of buildings and  in
 many industrial  settings.

 1.2  FEDERAL REGULATORY PROGRAMS

           Federal  regulations  pertaining  to asbestos-containing
 TSI include EPA's  National Emission Standards for  Hazardous  Air
 Pollutants (NESHAP)(40  CFR 61,  Subpart M),  the  Friable Asbestos-
 Containing Materials in Schools;  Identification and Notification
 Rule (47 FR 23360,  May  27, 1982;  40 CFR Part 763), and the
 Asbestos-Containing Materials  in  Schools; Final Rule  and Notice
 (52 FR 41826,  October 30, 1987; 40 CFR Part 763) promulgated
 under the Asbestos Hazard Emergency Response Act (AHERA).  The
 Occupational Safety and Health Administration  (OSHA)  regulates
 occupational exposure to asbestos (51 FR  22612,  June  20, 1986 and
 53  FR 35610,  September  14, 1988;  29 CFR Parts 1910 and 1926).

           In 1975,  NESHAP restricted the  installation or
 reinstallation of  friable asbestos-containing TSI  (40 FR 48292,
 October 12,  1975).   (Friable material is  material  that can be
 crumbled,  pulverized, or reduced  to powder  by hand pressure.)
 NESHAP also specifies standards for demolition  or  renovation
 involving at least 260  linear  feet or 160 square feet of friable
 asbestos materials.

           The 1982  Identification and Notification Rule required
 local  educational  agencies to  inspect all school buildings for
 friable materials  (including TSI) applied to structural surfaces;
 sample and analyze for  asbestos or treat  the material as
 asbestos-containing;  and inform employees and parent-teacher
 groups.   Under the AHERA rule,  inspection is extended to non-
 friable materials  and must be  performed by  an accredited
 inspector.   If asbestos-containing materials are identified, the
 local  educational  agency must  implement an  operations,
 maintenance,  and repair (O&M)  program and submit a management
 plan to the State  Governor.  Although AHERA applies only to
 schools,  some  private building owners and managers are using the
 regulation as  a basis for their asbestos  management programs.

           The  OSHA rules establish a permissible exposure limit
 (PEL)  of  0.2  fibers/cm3 as an eight hour time-weighted average
 and an  excursion limit  of 1.0  fibers/cm3 as a 30 minute time-
weighted  average measured by phase contrast microscopy (PCM).
Exposures  at or above the action  level of 0.1 fibers/cm3 trigger
various monitoring  and  medical  surveillance requirements.
Through the EPA worker  protection rule (40  CFR  Part 763, Subpart
G) and the AHERA rule,  OSHA  provisions are  extended to asbestos
abatement workers employed by  State and local government
employees and  operations and maintenance  workers employed by
local educational agencies.

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            2. CHARACTERISTICS OF ASBESTOS-CONTAINING
                    THERMAL SYSTEM INSULATION

          Information on asbestos-containing TSI in public and
commercial buildings is available from a 1984 national survey
(USEPA 1984a).  The target population consisted of Federal
government buildings, rental apartment buildings with 10 or more
dwelling units, and privately-owned buildings used primarily for
non-residential purposes.  A total of 231 buildings were
inspected for surfacing materials (sprayed- or trowelled-on
friable material),  TSI (pipe and boiler insulation),  and ceiling
tile.  Additional information collected during the survey, but
not included in the study report, is reported in Rogers (1988) .
The survey provides national estimates with a known degree of
accuracy.  Only the estimates are discussed here, since the
objective is to illustrate general trends rather than emphasize
numerical values.   Note, however that the estimates are not
precise and small differences between them are not significant.
Readers should consult the original reports for a measure of the
uncertainty associated with each estimate.

2.1  PREVALENCE

          The 1984 national survey provides three measures of
prevalence with respect to asbestos-containing TSI: the number of
buildings with asbestos-containing TSI; the percentage of
buildings with asbestos-containing TSI; and the total floor area
of buildings with asbestos-containing TSI.  The amount of
asbestos-containing TSI  (e.g., linear or square feet) was not
measured in the survey.  Therefore, buildings with a small amount
of asbestos-containing TSI are given the same weight as buildings
in which asbestos-containing TSI is present throughout the
building.

          All three measures of prevalence — number of
buildings, percent, and total floor area — provide useful
information on asbestos-containing TSI.  The number of buildings
with asbestos-containing TSI indicates the magnitude of the
problem in terms of the organizational effort involved.  The
percentage of buildings in different categories  (e.g.,
residential versus commercial) with asbestos-containing TSI may
be used to determine the most efficient use of limited resources.
For example, if two building categories contain the same number
of buildings, but the percentage of buildings with asbestos-
containing TSI in the first category is greater than the
percentage in the second category, inspection restricted to
buildings in the first category will identify a greater number of
buildings with asbestos-containing TSI per dollar  spent, than the
same inspection applied to all buildings.  The total floor area
of buildings with asbestos-containing TSI provides a rough
measure of the number of people potentially exposed, and,
possibly, the amount of  asbestos-containing material present.

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          Buildings with asbestos-containing TSI account for the
majority of public and commercial buildings with asbestos-
containing material  (Figure  1) .  Of  the  estimated 733,000
buildings with friable asbestos-containing material';  192,000 have
asbestos-containing surfacing  material and 563,000 have asbestos-
containing TSI.  These results imply that only about 22,000
buildings have both asbestos-containing  TSI and asbestos-
containing surfacing material.   (Asbestos-containing ceiling
tile, which is too rare to significantly affect the estimates,' is
ignored.)  Thus, the majority  of buildings with asbestos-
containing TSI. could implement a management program for TSI
immediately with little chance of having to extend5'it later to
include surfacing-material.
                                             xjxjx  Surfacing Only (170)
                                                  TSI & Surfacing (22)


                                                  TSI Only (541)
                                                  No ACM (2,873)
  Figure 1.  The estimated number of buildings  (in thousands)
  with asbestos-containing materials.

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          The corresponding estimated percentages are:   15
percent of all buildings have only asbestos-containing TSI; 1
percent have both asbestos-containing TSI and asbestos-containing
surfacing material; and 4 percent have only asbestos-containing
surfacing material.  Buildings with only asbestos-containing TSI
have an estimated total floor area of 13 billion square feet;
buildings with both asbestos-containing TSI and asbestos-
containing surfacing material have an estimated total floor area
of 3.8 billion square feet; and buildings with only asbestos-
containing surfacing material have an estimated total floor area
of 1.8 billion square feet.

          Asbestos-containing TSI is also the dominant form of
asbestos-containing material in schools.  A national telephone
survey (USEPA 1984b) estimated that 71 percent of local
educational authorities have one or more schools with asbestos-
containing TSI, and 45 percent have only asbestos-containing TSI.
On-site inspections of a subset of the schools indicated that
these percentages may be underestimated.  Some schools did not
realize that they were required to inspect TSI.

          The City of New York Department of Environmental
Protection has recently completed a survey of New York City
buildings grouped into 18 categories according to use (NYCDEP
1988).  TSI is present in an estimated 68 percent of the
buildings.  Overall, fewer than 0.5 percent have asbestos-
containing surfacing material.  However, surfacing material is
more prevalent in certain types of buildings.  For example, 28
percent of tall office buildings, 15 percent of hospitals, and 12
percent of theaters and places of public assembly have asbestos-
containing surfacing material.

          The sections below show how the incidence of asbestos-
containing TSI depends on building type, building age, and
building height.

          Building Type.  Figure 2a shows that the largest number
of buildings with asbestos-containing TSI are commercial, non-
residential buildings, followed by residential buildings of 10
units or more, and federal buildings.  However, since commercial,
non-residential buildings are by far the most numerous of the
three types of building, the percentage of commercial, non-
residential buildings with asbestos-containing TSI is low
compared to federal and residential buildings  (Figure 2b).  Floor
area of buildings with asbestos-containing TSI follows a similar
pattern to number of buildings  (Figure 2c).

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                (a) Number of Buddings (1.000's)

                     800 '
                     600  -
                     400  -
                     200  -
                                       ComrnwrcW   Al

                                  Type of Building
                  (b) Percent of Buildings

                      100
                           Fodsrsl   RwtoertW' Cormrwrciai   Al

                                  Type of Building
                 (c) Floor area
                     (Billions of square feet)
                      10 -
                       5 -
                                       CommcrcW   Al

                                  Type of Building
Surfacing only:

TSI & Surfacing

TSI only
                                                     |   | Surfacing only

                                                     |   j TSI & Surfacing

                                                     Fd TSI only
                                                      |  | Surfacing only

                                                      fcff:l TSI & Surfacing

                                                      MM TSI only
Figure 2.    The relationship between type  of  building  and type  of
ACM;  a)  estimated number of buildings;  b)  estimated percent of
buildings;  c)  estimated total  floor area.

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       eo
CO
o>
TJ
'5

"5
o>
|
Z
           400
           300
           200
           100
                 Up to 1944  1945-1959  1960-1969  1970-1978

                          Construction Date
  Figure 3.   The relationship between building  construction date
  and presence of asbestos-containing material.
          Building Age.  The majority of buildings with asbestos-
containing thermal system  insulation were constructed prior to
1944 (Figure 3).  The use  of asbestos-containing TSI declined
during the 1950's and 60's.  NESHAP further limited its use in
the mid 1970's.  In contrast,  use of surfacing asbestos-
containing material peaked in  the 1960's.  The total numbers of
buildings in each age category are roughly equal, thus the
percentage of buildings with asbestos-containing TSI as a
function of age follows the same pattern as the number of
buildings with asbestos-containing TSI.

          Building Height.  Buildings with three to seven floors
represent the greatest number  of buildings with asbestos-
containing thermal system  insulation (Figure 4a).  Compared to

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shorter buildings  (1-2 floors), few of these buildings contain
surfacing material.  Figure 4b shows that although buildings of 8
floors or more are rare relative to shorter buildings, almost 100
percent of these tall buildings contain asbestos-containing TSI,
and an estimated 40 percent contain both asbestos-containing
surfacing material and asbestos-containing TSI.  Due to their
size, the estimated floor area of buildings of 8 floors or more
with asbestos-containing TSI  (5.3 billion square feet) represents
a significant proportion of the total estimated floor area of
buildings with asbestos-containing TSI (16.8 billion square
feet).

          Geographical Region.  Although the 1984 national survey
was not designed to provide estimates by region, some qualitative
trends were observed.  Buildings in the east and midwest are more
likely to have central heating and hence TSI.  Buildings in the
west, southwest, and southeast are less likely to have central
heating except in larger buildings.


2.2  ASBESTOS CONTENT

          Asbestos-containing TSI has a higher estimated asbestos
content (70 percent) than surfacing material (14 percent) or
ceiling tile (3 percent).  However, since asbestos-containing TSI
is generally protected by a non-asbestos cover or wrap, the
higher asbestos content does not necessarily imply a higher
exposure,  particularly if the material remains undisturbed.
                                8

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                 (a) Number of BuNdlnga (1,000's)

                       400
                       300  -
                               1-2       3-7     8 or more

                                 Height of Building (floors)

                    (b) Percent of Buildings

                       100
                        80
                        GO
                        40
                        20
                   (c) Floor area
                       (Billions of square feet)

                         B
                               1-2      3-7     8 or more

                                 Height of Building (floors)
                               1-2       3-7     8 or more

                                  Height of Building (floors)
|   | Surfacing only

EH TSI & Surfacing

    TSIonly
I  | Surfacing only

HI TSI & Surfacing

   TSI only
                                                        |   | Surfacing only

                                                        ["I TSI & Surfacing

                                                        n TSIonly
Figure  4.   The relationship  between building  height and type of
ACM;  a)  estimated number  of  buildings; b)  estimated percent  of
buildings;  c)  estimated total  floor area.

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 2.3  CONDITION

           Each area of TSI  in the 1984  national  survey was
 classified into one of three categories:  good condition, moderate
 damage,  and significant damage (Rogers  1988).  An  estimated
 453,000  buildings have at least some  damaged asbestos-containing
 TSI and  an estimated 317,000 buildings  have  at least  some
 significantly damaged asbestos-containing TSI (Figure 5).  These
 numbers  correspond to 13 percent and  9  percent of  all buildings,
 respectively.   Note that,  since the amount of TSI  was not
 measured,  the amount of damaged asbestos-containing TSI  within a
 building is not necessarily large.  Nevertheless,  the estimates
 indicate that some action,  such as  repair, might be appropriate
 in  a majority of buildings  with asbestos-containing TSI.

           The City of New York Department of Environmental
 Protection reached a similar conclusion based on the  results  of
 its survey (NYCDEP 1988).   Overall, 19  percent of  TSI is in poor
 condition,  and another 68 percent is  in fair condition.  The  city
 has introduced legislation  requiring  inspection  for asbestos-
 containing materials (both  TSI and  surfacing)  for  all buildings
 and,  when asbestos is found,  an operation and maintenance
 program,  management plan and response actions.

           The sections below indicate how condition of asbestos-
 containing TSI identified in the EPA  national survey  is  related
 to  building type and building height.

           Building Type.  Commercial, non-residential buildings
 constitute the majority of  buildings  with at least some  damaged
 asbestos-containing TSI and the majority  of  these  contain at
 least some significantly damaged asbestos-containing  TSI (Figure
 6a).   Despite the smaller percentage  of commercial, non-
 residential buildings with  asbestos relative to  federal  or
 residential buildings,  the  percentage of  commercial,  non-
 residential buildings with  at least some  significant  damage is
 greater  than in either of the other two building types  (Figure
 6b).   This  suggests that although asbestos-containing thermal
 system insulation is less common in commercial,  non-residential
 buildings,  it is more likely to be  damaged when  it is present.
 The  floor  area of buildings in the  three  condition categories
 follows  a  similar pattern to the number of buildings  (Figure  6c).

          Building Age.2  The older the building, the more likely
 it  is  to contain damaged asbestos-containing TSI (Figure 7).
 Buildings constructed prior to 1944 account  for  the majority  of
 buildings with at least some significant  damage.
     Information on building age was obtained from a memo
written by John Rogers, Westat to Joan Blake and Cindy Stroup,
EPA dated March 9, 1987.

                                10

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                                              No damage (110)
                                          /// Some moderate
                                              Some significant
                                              damage (317)

                                              No asbestos-containing
                                              TSI (3,043)
  Figure 5.   The number of buildings  (in thousands)  that  have no
  asbestos-containing TSI, TST with no damage, TSI with some
  moderate damage only; and TSI with  some significant  damage.
          Building Height.  The  results for buildings of 8 floors
or more should be interpreted  cautiously because they are based
on  inspection of a small number of  buildings.   The number of
buildings that have at  least some significantly damaged asbestos-
containing TSI appears  to be greatest for buildings of 3 to 7
floors (209,000), and least for  buildings 8 floors or more
(2,000) (Figure 8a).  Although only  a small percentage of
buildings of 8 floors or more  have significantly damaged
asbestos-containing material,  an estimated 78 percent have at
least some damaged material  (Figure  8b).   The floor area
represented by buildings in each of  the three condition
classifications is roughly comparable across building height
(Figure 8c).
                                11

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               (a) Number of Buildings (1,000's)
                     600
                     500

                     400

                     300

                     200

                     100
|   | good condition
[::::::::::::| moderate damage
   significant damage
                          F«d«r*   Fta&tenW ComnwreW
                                Type of Building
                 (b) Percent of Buildings
                    100
                     80
                     60
                     40
                     20
                               RMfcfenW Commwtd*
               (c) ROOT area          Type of Building
                   (Billions of square feet)
                     20
|   | good condition
[vXvX] moderate damage
   significant damage
                     15
                     10
|  | good condition
[^J moderate damage
E3 significant damage
                                     Comrrwo*
                                Type of Building
Figure 6.   The  relationship between  type of building  and
condition of  asbestos-containing  TSI; a)  estimated number of
buildings in  each condition category, b)  estimated percent  of
buildings, c)  estimated total  floor  area.
                                         12

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                 (a) Number of Buildings (1,000's)

                       400
                       300
                       200
                       100
|  | good condition

[XvXvj moderate damage

   significant damage
                            Up to 1944 1945-1958  1080-1908  1870-1879

                                   Construction Date

                   (b) Percent of Buildings

                       100
                        80
                        60
                        40
                        20
|   | good condition

|:   | moderate damage

fc: "j significant damage
                  (c) Floor area
                      (Billions of square feet)

                        10
                            Up to 1944 1945-1959  1980-1989 1970-1979

                                   Construction Date
                                                        |  | good condition

                                                        P:-:-Xv| moderate damage

                                                           significant damage
                            Up to 1944 1945-1858  1800-1969 1970-1879

                                   Construction Date
Figure  7.   The relationship between building construction  date
and condition  of  asbestos-containing TSI;  a)  estimated number  of
buildings  in each condition category,  b)  estimated percent of
buildings,  c)  estimated total floor area.
                                          13

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             (a) Number at BufcNngs (1,000's)

                   400
                   300 -
                   200 -
                    100 -
 |  | good condition

' t::::::::::l moderate damage

    significant damage
                           1-2    -  3-7     8 or more

                             Height of Building (floors)
                (b) Percent of Buildings

                    100
                                                   |   | good condition

                                                   |::::::>::::] moderate damage

                                                       significant damage
                           1-2       3-7     8 or more

               (c) Floor area       Height of Building (floors)

                   (Billions of square feet)

                     8
                                   ^.-
                                 --»-«*-• !•:;•:•
                                                       good condition

                                                       moderate damage

                                                       significant damage
                           1-2      3-7     8 or more

                             Height of Building (floors)
Figure 8.   The  relationship  between building height and  condition
of  asbestos-containing TSI;  a)  estimated  number of buildings  in
each  condition  category,  b)  estimated percent  of buildings,  c)
estimated total floor area.
                                          14

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2.4  LOCATION

          The 1984 national survey recorded the location of
asbestos-containing materials (surfacing,  TSI,  and ceiling tile)
as either in fan and boiler rooms or in public  areas.   A separate
analysis of the location of asbestos-containing TSI has not been
performed.  Nevertheless, some inferences  can be made from the
aggregated data.  An estimated 462,000 buildings have asbestos-
containing material in fan and boiler rooms (Figure 9)  and this
material is almost entirely TSI (J. Rogers, personal
communication).  At least an estimated 262,000  buildings have
asbestos-containing TSI in public areas.  (Some buildings have
asbestos-containing TSI in both fan and boiler  rooms and in
public areas.)  These results indicate that although asbestos-
containing TSI is typically associated with restricted areas such
as fan and boiler rooms, and the greatest  amount of material is
probably located there, a substantial number of buildings have at
least some asbestos-containing TSI in public areas.

          An estimated 360,000 buildings have some damaged
asbestos-containing TSI in fan and boiler  rooms, and an estimated
282,000 have some significantly damaged asbestos-containing TSI
in fan and boiler rooms.  At least 217,000 buildings have some
damaged asbestos-containing TSI in public  areas, and at least
85,000 buildings have some significantly damaged asbestos-
containing TSI in public areas.

          The location of asbestos-containing material in general
(surfacing, TSI, and ceiling tile) is related to building
height.  Since asbestos-containing thermal system insulation is
the most prevalent type of asbestos-containing material, the
location of asbestos-containing TSI is likely to have a similar
relationship with building height.  Buildings with 1 or 2 floors
are more likely to have asbestos-containing material only in
public areas.   (These buildings account for most of the surfacing
material.)  Buildings of 3 to 7 floors are more likely to have
asbestos-containing material restricted to fan and boiler rooms,
and buildings of 8 floors or more tend to have ACM in both public
areas and fan and boiler rooms.

          The New York City survey  (NYCDEP 1988) does provide
location information specifically for TSI.  To the extent that
New York City buildings are representative of buildings in other
parts of the U.S., the data may provide additional insight into
where asbestos-containing TSI is likely to be found in buildings.
                                15

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                                          m-:-\ Public Only (271)

                                              F&BRoom&Public(183)

                                              F&B Room Only (279)

                                              No ACM (2,873)
  Figure 9.   The estimated number of buildings (in thousands)
  with asbestos-containing material in fan and boiler rooms and
  in public  areas.
2.5  AIRBORNE ASBESTOS LEVELS

          Research on_exposure to airborne asbestos  in  buildings
has focused on surfacing material (e.g., USEPA  1980,  1983, ,1985a,
1986, Tuckfield et al 1988).  Consequently,  information on
ambient airborne asbestos levels in buildings with asbestos-
containing TSI is restricted to two studies  - a recent  EPA  study
(USEPA 1988) and Burdett and Jaffrey  (1986).  Neither study was
designed specifically to investigate TSI.

          The EPA study measured airborne asbestos levels in 49
buildings in the United States using transmission electron
microscopy  (TEN) and a direct transfer sample preparation
technique.  The buildings, which were selected  according to the
presence and condition of the asbestos-containing material,
                                16

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consisted of six buildings with no asbestos-containing material
(Category 1),  six buildings with asbestos-containing material in
generally good condition (Category 2) ,  and 37 buildings with some
damaged material (Category 3).   Forty of the buildings contained
asbestos-containing TSI and 15  contained only asbestos-containing
TSI.  Although airborne asbestos levels were low in absolute
magnitude across all building categories,  there is an increasing
trend in average airborne asbestos levels.  Outdoor measurements
are lowest followed by building categories 1, 2 and 3 .   Figure
10 shows that in this study, buildings with only asbestos-
containing TSI followed the same trend.


          Burdett and Jaffrey (1986)  included 24 buildings with
warm air heaters containing asbestos in a study of airborne
asbestos levels in 43 buildings in the United Kingdom.  Samples
were analyzed by TEM using a direct preparation technique similar
to that used in USEPA (1988).  The authors concluded that only in
one building were sufficient asbestos fibers collected to provide
an estimate of airborne asbestos concentration (0.002 f/cm ) .
All other samples were below the level of quantification.

          Airborne fiber levels during disturbance of asbestos-
containing TSI have been measured by phase contrast microscopy
(PCM).  PCM counts only fibers longer than 5 micrometers, does
not distinguish asbestos fibers from other types of fibers such
as cellulose and fiber glass, and cannot detect thin fibers
(fibers with diameters less than 0.25 micrometers).  Therefore,
PCM results cannot be compared directly with TEM results.
Pinchin (1982) monitored airborne asbestos levels before, during,
and after removal of block-type boiler and pipe insulation from
equipment that was being dismantled.  The removal proved
difficult because the material was not easily wetted.  Airborne
fiber levels measured by PCM while work was in progress ranged
from over 5.0 f/cm3 at the beginning of the removal to 1.0 f/cm3
as work practices improved.  Two air samples analyzed by TEM
before the work began measured an average airborne  asbestos
concentration of 0.9  f/cm3. After clean-up the estimated
airborne asbestos concentration was 1.8 f/cm3.   The author
implies that there was an unidentified, additional source of
asbestos fibers, but does not elaborate.
      Note that methods for measuring and reporting airborne
asbestos vary and refinements are constantly being made.  EPA
currently reports asbestos structures per cubic centimeter  of  air
to emphasize that other structures  (bundles, clusters, matrices),
in addition to fibers, are included in the count.  Some
researchers state their results as fibers per cubic centimeter of
air irrespective of the type of asbestos structures counted.

                                17

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         Outdoor
         Category 1
         (No ACM)
        Category 2
      (Good Condition)
        Category 3
        (Damaged)
                                           All Sites
                                           Bldgs with TSI only
                  0       0.0002     0.0004     0.0006     0.0008

                     Median Average Airborne Asbestos Cone, (s/cc)
  Figure 10.  In EPA's study  of public buildings  (USEPA  1988),
  average airborne asbestos levels in 15 buildings with  only TSI
  followed a similar trend to that observed in all 49 buildings.


          Despite  the  use of  glove bags to restrict  fiber
movement, NIOSH  (1987)  recorded average fiber  levels of  0.3, 0.3,
0.6, and 0.006 f/cm3 by PCM at four sites during removal of  pipe
insulation.  The low level measured at the fourth site may be
due, in part, to improved work practices as the workers  became
more experienced.

          In the supplementary information to  the OSHA final
rules  (51 FR 22612), estimated exposure during routine
maintenance in commercial and residential buildings  (which
presumably  includes  maintenance involving TSI) is 0.29 f/cm
(mean  8 .hour/ time-weighted average measured by PCM) .  The OSHA
rules  also  cite data indicating airborne fiber levels of 0.01 to
0.57 f/cm3  with a geometric  mean of 0.09 f/cm3 during wet
removal of  asbestos-containing pipe insulation.
                                 18

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          Although the data are not extensive,  they indicate that
elevated airborne fiber levels can occur during disturbance of
asbestos-containing TSI,  and strongly support the need for
special precautions when working with or near asbestos-containing
TSI.  Note that many of the reported levels exceed current OSHA
standards and would trigger worker protection and surveillance
requirements.
                                19

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20

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    3.  MANAGING ASBESTOS-CONTAINING THERMAL SYSTEM INSULATION


          "Guidance for Controlling Asbestos-Containing Materials
in Buildings" (USEPA 1985b),  popularly referred to as the "Purple
Book," describes the steps a  building manager or owner should
follow to identify and manage asbestos-containing material4.
They are:

          1.   Determine if asbestos-containing material is
               present;

          2.   Establish a special operations and maintenance
               (O&M) program;

          3.   Assess the need for further action; and

          4.   Implement response actions as appropriate.

Readers should consult the Purple Book and other reference
sources before implementing these steps.  This section provides
an overview of the material in the Purple Book, but is not
intended as a substitute for detailed guidance provided by EPA
and other organizations.  Schools must comply with AHERA
requirements.

          The building owner should appoint an asbestos program
manager to direct all asbestos-related activities.  Depending on
the size and nature of the building, the asbestos program manager
may be supported by various in-house and external personnel.
Building owners with successful asbestos management programs
often emphasize the importance of communication and cooperation
with occupants, tenants, contractors, and others who visit or
work in the building.

3.1  DETERMINING IF ASBESTOS-CONTAINING MATERIAL IS PRESENT IN A
BUILDING

          The building is inspected carefully to identify all
potential asbestos-containing material.  EPA recommends that
undamaged TSI be left undisturbed and assumed to be asbestos-
containing until there is a need for maintenance or other
activities that are likely to disturb the material.  When the
need arises, samples are collected and analyzed by a qualified
laboratory using polarized light microscopy  (PLM) to determine
whether or not asbestos is present.   (The National Institute  of
Technology and Standards, formerly the National Bureau of
     *The Purple Book may be obtained from your EPA Regional
Asbestos Coordinator, or by calling the Toxic Substances  Control
Act Assistance Office at  (202) 554-1404.
                                21

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Standards,  maintains  a  list  of  accredited  PLM  laboratories.)
Damaged  insulation  should  be sampled where the material  is
exposed.   (AHERA does not  require  schools  to sample TSI
determined  by  an accredited  inspector  to be fiberglass,  foam
glass, or rubber.)

          Accurate  labelling and record keeping are particularly
important for  TSI because  the nature of the material may vary
within a small area.  For  example, while pipe  insulation on
straight runs  may be  asbestos free, material on joints and elbows
may contain asbestos.   Clear labelling of  sampling locations,
whether  asbestos-containing  or  asbestos-free,  prevents
unnecessary resampling  at  the time of  maintenance or repair.
Warning  labels attached to asbestos-containing material  reduce
the likelihood of accidental disturbance,  particularly by
individuals such as plumbing or heating contractors who  may be
unfamiliar  with the building.

3.2  ESTABLISHING AN  OPERATIONS AND MAINTENANCE PROGRAM

          A special O&M program is established whenever  asbestos-
containing  material is  present  or  assumed  to be present  in a
building.   The plan is  designed to clean up asbestos fibers
previously  released,  prevent future release by minimizing
disturbance or damage,  and monitor the condition of the  material.
While details  will  vary from building  to building, a key element
of an O&M program for asbestos-containing  TSI  is a job approval
system that ensures that work with or  near asbestos-containing
TSI will not occur  without appropriate precautions.  EPA is
currently preparing a new  guidance document on O&M programs.

3.3  ASSESSING THE  NEED FOR  FURTHER ACTION

          The  need  for  further  action  is based on an assessment
of the current condition of  the material,  the  potential  for
future fiber release, and  building renovation  and replacement
plans.  The relative  risks and  costs of different options must be
carefully weighed.  In  many  cases, the decision for asbestos-
containing  TSI may Joe, a continuing O&M plan combined with repair
of any damaged material as soon as the damage  is detected.

3.4  IMPLEMENTING RESPONSE ACTIONS

          Response  actions for  asbestos-containing TSI include
repair (including encapsulation),  enclosure, and, in extreme
cases, removal.   Where  possible, repair is the generally
recommended action  for  damaged  asbestos-containing TSI.
Enclosure can  be  used to minimize  future disturbance.  For
example,  pipes  running  through  a public corridor may be  enclosed
to prevent  building occupants deliberately or  accidentally
damaging the insulation.   Removal  is necessary when the  material
is so badly damaged that it  no  longer  performs its insulating

                                22

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function, or when system components must be repaired or replaced.
Response actions involving asbestos-containing TSI may be less
costly than those involving surfacing material because they often
take place in restricted areas with minimal disruption to
building occupants.  Elaborate procedures may be needed, however,
if the asbestos-containing TSI is associated with the air
handling system and the building must remain operational during
performance of the work.

          Procedures for response actions are described in the
Purple Book, in "Abatement of Asbestos-Containing Pipe
Insulation" (EPA Technical Bulletin 1986-2) and the National
Institute of Building Sciences Model Guide Specifications (NIBS
1986).  Containment of the work area is generally required.
Response actions should be performed only by trained and
qualified individuals.  For work involving a small amount of
asbestos-containing TSI, glove bags provide a practical
alternative to constructing containment barriers around the work
area.  As with all forms of asbestos abatement, effective use of
glove bags requires training and experience (NIOSH 1987).  EPA
recommends the wearing of respirators and protective clothing
while using glove bags.
                                23

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24

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                           REFERENCES


Burdett GJ, Jaffrey SAMT.  1986.   Airborne asbestos concentrations
     in buildings.  Annals of Occupational Hygiene 30:185-199.

NIBS. 1986. National Institute of Building Sciences.   Model Guide
     Specifications: Asbestos Abatement in Buildings.  Washington,
     DC: National Institute of Building Sciences.

NIOSH. 1987.  National Institute for Occupational  Safety and
     Health.  An evaluation of glove bag containment  in asbestos
     removal.  Cincinnati, OH: U.S.  Department of  Health and
     Human Services.

NYCDEP.  1988.  City of New York Department of Environmental
     Protection.  Final report on the assessment of the public's
     risk of exposure to in-place asbestos.  December 1, 1988.

Rogers J. 1988.  Additional analysis of data collected in the
     asbestos in buildings survey.  Draft Final Report.
     Washington, DC: Office of Toxic Substances, USEPA. Contract
     68-02-4243.

Tuckfield RC, Tsay Y, Margeson DP et al. 1988.  Evaluation of
     asbestos abatement techniques,  phase 3: removal.   Draft
     Final Report.  Washington, DC:  Office of Toxic Substances,
     USEPA.  Contract 68-02-4294.

USEPA. 1980. U.S. Environmental Protection Agency.  Measurement
     of asbestos air pollution inside buildings with sprayed
     asbestos. Washington, DC: Office of Toxic Substances, USEPA.
     EPA 560/13-80-026.

USEPA. 1983. U.S. Environmental Protection Agency.  Airborne
     asbestos levels in schools. Washington, DC: Office of Toxic
     Substances, USEPA. EPA 560/5-83-003.

USEPA. 1984a. U.S. Environmental Protection Agency.  Asbestos  in
     buildings: National survey of asbestos-containing  friable
     materials. Washington, DC: Office of Toxic Substances,
     USEPA. EPA 560/5-84-006.

USEPA. 1984b. U.S. Environmental Protection Agency. Evaluation of
     the asbestos-in-schools  identification and notification
     rule. Washington, DC: Office of Toxic Substances,  USEPA.  EPA
     560/5-84-006.

USEPA. 1985a. U.S. Environmental Protection Agency. Evaluation of
     asbestos abatement techniques, phase  1:  removal.  Washington,
     DC: Office of Toxic Substances, USEPA. EPA 560/5-85-019.


                                25

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USEPA. 1985b. U.S. Environmental Protection Agency. Guidance for
     controlling asbestos-containing materials in buildings.
     Washington, DC: Office of Toxic Substances, USEPA. EPA
     560/5-85-019.

USEPA. 1986. U.S. Environmental Protection Agency. Evaluation of
     asbestos abatement techniques, phase 2: encapsulation with
     latex paint. Washington, DC: Office of Toxic Substances,
     USEPA. EPA 560/5-86-016.

USEPA. 1988. U.S. Environmental Protection Agency. Assessing
     asbestos exposure in public buildings. Washington, DC:
     Office of Toxic Substances, USEPA. EPA 560/5-88-002.
                                26

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APPENDIX A
     27

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28

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         APPENDIX A.  EPA REGIONAL ASBESTOS COORDINATORS
EPA Region 1
JFK Federal Building
Boston, MA 02203
(617) 565-3273
(Connecticut, New Hampshire,
Rhode Island, and Vermont)

EPA Region 2
Woodbridge Avenue
Edison, NJ 08837
(201) 321-6668
(New Jersey, New York, Puerto
Rico, and Virgin Islands)

EPA Region 3
841 Chestnut Street
Philadelphia, PA 19107
(215) 597-9859
(Delaware, District of
Columbia, Maryland,
Pennsylvania, Virginia, and
West Virginia)

EPA Region 4
345 Cortland Street, N.E.
Atlanta, GA 30365
(404) 347-5053
(Alabama, Florida, Georgia,
Kentucky, Mississippi, North
Carolina, South Carolina, and
Tennessee)

EPA Region 5
230 S. Dearborn Street
Chicago, IL 60604
(312) 886-6003
(Illinois, Indiana, Michigan,
Minnesota, Ohio, and
Wisconsin)
EPA Region 6
Allied Bank Tower
1445 Ross Avenue
Dallas, TX 75202
(214) 655-7244
(Arkansas, Louisiana, New
Mexico, Oklahoma, and Texas)

EPA Region 7
726 Minnesota Avenue
Kansas City, KS 66101
(913) 236-2835
(Iowa, Kansas, Missouri, and
Nebraska)

EPA Region 8
One Denver Place
999 18th Street, Suite  500
Denver, CO 80202-2405
(303) 293-1744
(Colorado, Montana, North
Dakota, Utah, and Wyoming)

EPA Region 9
215 Fremont Street
San Francisco, CA 94105
(415) 974-7290
(Arizona, California, Hawaii,
Nevada, American Samoa, and
Guam)

EPA Region 10
1200  6th Avenue
Seattle, WA 98101
(206) 442-2870
(Alaska,  Idaho,  Oregon, and
Washington)
                                29

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30

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APPENDIX B
     31

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32

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         APPENDIX B.  SOURCES OF ADDITIONAL INFORMATION
General:
     Guidance for controlling asbestos-containing materials in
     buildings (Purple Book).  U.S.  Environmental Protection
     Agency. 1985. Washington,  DC:  Office of Toxic Substances,
     USEPA. EPA 560/5-85-019.

     Toxic Substances Control Act Assistance Office:  (202) 554-
     1404.

Operations and Maintenance:

     Asbestos in Buildings: Guidance for Service and Maintenance
     Personnel.  U.S. Environmental Protection Agency.   1985.
     Washington, DC: Office of Toxic Substances, USEPA. EPA
     560/5-85-018.

Abatement:

     Abatement of Asbestos-Containing Pipe Insulation.   U.S.
     Environmental Protection Agency.  1986.  Washington, DC:
     Office of Toxic Substances, USEPA.  Technical Bulletin
     1986-2.

     National Institute of Building Sciences.  Asbestos Abatement
     and Management in Buildings: Model Guide Specifications.
     August 1988.  Washington, DC: National Institute of Building
     Sciences.
                                33

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   50372-IQ1
    REPORT DOCUMENTATION
             PAGE
1. REPORT NO.
 EPA 560/5-88-007
                                                          3. Recipient's Accession No.
   4. Title and Subtitle
       Asbestos Containing Thermal System Insulation: Facts and Figures
                                                          5. Report Date
                                                          [March. 1990
   7. Authors)
       Chesson, J.
                                                          8. Performing Organization Rept. No.
   9. Performing Organization Name and Address
       Chesson Consulting, Inc., 1717 Massachusetts Ave, NW, Washington, DC 20036

       Battelle, Arlington Office, 2101 Wilson Boulevard, Arlington, VA 22201
                                                           10. Preiect/Taf k/Work Unit No.
                                                           11. Contract(C) or Grant(G) No.
                                                           (C)68-02-4294

                                                           (G)
   12. Sponsoring Organization Name and Address
       U.S. Environmental Protection Agency
       Office of Toxic Substances
       Exposure Evaluation Division (TS-798)
       401 M Street, SW, Washington, DC 20460
                                                           13. Type of Report & Period Covered
                                                          Peer-reviewed report
                                                           14.
   IS. Supplementary Notes
   16. Abstract (Limit: 200 words)
       This document provides information on the characteristics of asbestos-containing thermal system insulation (TSI)
       and lists resources available to individuals who are responsible for making asbestos management decisions.  The
       primary source of information is an U.S. EPA national survey that was conducted in 1984 to determine how
       many buildings contain asbestos.  Recent analysis of data not included in the original study report provides
       additional information on condition of the asbestos-containing material.

       Of the 733,000 buildings estimated to contain asbestos, most (about 563,000) have asbestos-containing TSI.
       Many fewer (about 192,000 buildings) have asbestos-containing surfacing material.  Of the building categories
       covered by the survey, residential apartment buildings, buildings built prior to 1944, and buildings of 8 floors or
       more are most likely to have asbestos-containing TSI.  Over half the buildings with asbestos-containing TSI have
       some significantly damaged TSI and 80 percent have at least some damaged TSI.  TSI is more likely to be
       damaged in commercial  non-residential buildings, in buildings constructed prior to  1944, and in buildings of 8
       floors or more.

       Since friable asbestos is restricted to TSI in many buildings, the majority of asbestos control programs will not
       need to address asbestos-containing surfacing material.
  17. Document Analysis  «. Descriptors
      Asbestos, thermal system insulation, surfacing material, damage, public buildings, commercial buidlings,
      residential buildings
     b. Identlfiers/Opcn-Ended Terms
    c. COSATI field/Group
 IB. Availability Statement
                                        19. Security Class (This Report)
                                        Unclassified
                                                                                  Class (This Page)
21. No. of Pages
 37
                                                                                                        22. Price
(See ANSI-Z39.18)
                                                    See instructions on Reverse
                                                                       OPTIONAL FORM 272 (4-77)
                                                                       (Formerly NTIS-35)
                                                                       Department of Commerce

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