United States Industrial Environmental Research EPA-600 2-80-088
Environmental Protection Laboratory May 1980
Agency Research Triangle Park NC 27711
Research and Development
Evaluation of a
Commercial Vacuum
System for the Removal
of Asbestos
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
EPA REVIEW NOTICE
This report has been reviewed by the U.S. Environmental Protection Agency, and
approved for publication. Approval does not signify that the contents necessarily
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This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161:
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EPA-600/2-80-088
May 1980
Evaluation of a Commercial
Vacuum System for the
Removal of Asbestos
by
R.W. Welker, D.F. Finn, J.D. Stockham,
and R.P. Hancock
I IT Research Institute
10West 35th Street
Chicago, Illinois 60616
Contract No. 68-02-2617
Task No. 10
Program Element No. C1Y-L1B
EPA Project Officer: David C. Sanchez
Industrial Environmental Research Laboratory
Office of Environmental Engineering and Technology
Research Triangle Park, NC 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, DC 20460
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ABSTRACT
Personal, area and environmental asbestos exposures resulting from wet
and dry asbestos removal using a commercial vacuum system were measured in
a brief field study. Personal and area (indoor) asbestos concentrations
during dry removal were less than one fiber per cm3, as measured by NIOSH
P&CAM 239 when the vacuum system was used. Asbestos released to the environ-
ment from the vacuum system's three-stage exhaust filter was negligible.
Asbestos was released from the system operator's protective garments when
he exited the work area to service the vacuum system.
Sources of asbestos fiber release associated with vacuum system opera-
tion were identified; these occurred during operation disassembly and asbestos
disposal. Following vacuum shutdown, liquid drained out of the collection
reservoir due to inadequate door seals. During vacuum hose disassembly,
bulk losses of asbestos-containing materials occurred. During disposal,
the exterior of the vacuum truck became contaminated as the reservoir was
emptied. The need for additional dry removal testing has been clearly
identified.
This report is submitted in partial fulfillment of Contract No. 68-
02-2617 by IIT Research Institute under the sponsorship of the U.S. Environ-
mental Protection Agency. The study covered the period October 21, 1979
to December 21, 1979, and work was completed as of February 4, 1980.
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IV
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CONTENTS
Abstract iii
Figures vii
Tables vftl
Acknowledgment , ix
1. Introduction 1
2. Conclusions 3
3. Recommendations 4
4. Background 5
Site Description 5
Site Preparation 5
Safety Considerations 8
Vacuum System Description 8
Wet and Dry Removal Methods 10
5. Methods'. 12
Background Sampling 12
Wet Removal Methods 12
Wet Removal I .12
Wet Removal II 15
Dry Removal Methods 15
Dry Removal 1 15
Dry Removal II 17
System Disassembly and Asbestos Disposal 17
6. Sampling and Analysis Procedures 22
Sampling 22
Vacuum Truck Sampling 22
Bulk Samples and Area Wipes 22
Personal, Area, and High-Volume Sampling 22
Analysis 23
Phase-Contrast Microscopy 23
Polarized Light Microscopy 25
Electron Microscopy 25
X-Ray Diffraction 25
Fibrous Aerosol Monitor 26
7. Results and Discussion 29
Background Sampling and Bulk Material Analysis 29
Bulk Material Analysis 29
Background Sample Analysis 29
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CONTENTS (continued)
Personal, Area, and Environmental Asbestos 3?
Concentrations 3g
Vacuum System Collection Efficiency 37
Wet Versus Dry Removal 37
System Disassembly and Asbestos Removal 3g
Additional Observations
Appendices:
40
A. Vacuum System Description ...................
B. Bulk Sample and Wipe Sample Analysis Procedures:
Polarized Light Microscopy and X-Ray Diffraction ....... ^
C. Personal, Area, and High-Volume Sample n
Analysis Procedures ......................
D. Fibrous Aerosol Monitor Description and Operation ....... 73
VI
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FIGURES
Number Page
1 Photograph of a delanrinating ceiling material in
FAA Radar Facility 6
2 Garage area at FAA Radar Facility 7
3 Schematic of truck-mounted vacuum system 9
i- * ' . i *
4 Background sampling locations 13
5 Sampling locations during Wet Removal I . 14
6 Sampling locations during Wet Removal II 16
7 Sampling locations during Dry Removal I, 18
»
8 Sampling locations during Dry Removal II , 19
9 Photograph of truck in dumping, position. . 20
10 Sampling locations during asbestos disposal 21
11 Photograph of personal sampling pump attached to worker. .... 24
vn
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TABLES
Number Page
1 Airborne Fiber Concentrations During Wet and Dry
Removal Methods 11
2 Statistics of the Asbestos Materials Used for
FAM Calibration 27
3 Recommended FAM Control Settings for Known Asbestiform
Fiber Types 28
4 Bulk Material Analysis of Ceiling Material by PLM 30
5 Background Fiber Concentrations . 31
6 Analysis of Area Wipe Samples by Polarized Light Microscope. . . 33
7 Personnel Exposure During Asbestos Removal 34
8 Indoor and Outdoor Area Concentrations During Asbestos
Removal Operations 35
9 Vacuum System Filtration Efficiency 36
10 Comparative NIOSH Method and FAM Fiber Concentrations 39
vm
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ACKNOWLEDGMENTS
Several individuals and organizations contributed to the success of
this study. The authors wish to express their gratitude to Mr. Jerry Regan
of the Environmental Protection Agency (EPA), Revion V, and Dr. Jack Wagman
of EPA's Environmental Sciences Research Laboratory for the loan of the
fibrous aerosol monitors; to Dr. Joseph Breen of EPA's Office of Pesticides
and Toxic Substances and the Technical Project Officer, Mr. David Sanchez
of EPA's Industrial Enviromental Research Laboratory, for their valuable
assistance and guidance; to Mr. Edward Swoszowski, Jr., and Mr. Harold Kraus
of Environmental Technology, Inc., who directed the removal operations; to
Mr. Robert DeMane of Diversified Vacuum Systems, Inc. for providing sampling
ports and data on the vacuum system; and, finally, to Mr. Alden Cole of the
Federal Aviation Administration facility at Bucks Harbor, Maine, for his
cooperation and hospitality.
IX
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SECTION 1
INTRODUCTION
The U.S. Environmental Protection Agency (EPA) is concerned with the
release of asbestos into the environment during demolition or renovation
of buildings containing functional or decorative asbestos. Whereas guidelines
currently exist for wet removal procedures which minimize worker exposure
and environmental contamination, wet removal cannot be tolerated in all places
where friable asbestos materials exist and must be removed; nor is information
presently sufficient to allow the EPA to prescribe guidelines for dry asbestos
removal, with or without a vacuum system, where site conditions prohibit
wet removal. A preliminary study was thus undertaken to assess personal
exposure and environmental emissions associated.with a commercially available
asbestos removal and collection system.
In summary, the objectives of this program were to:
• .determine the ambient and building interior asbestos
concentrations before, during, and after asbestos
removal using a commercial vacuum system,
• determine the collection efficiency of each stage of
the vacuum collection system and of the system as a
whole, and
• determine the level of asbestos emissions associated
with the operation and disassembly of the system and
the transfer of the collected asbestos to the
ultimate disposal site.
The objectives were partially accomplished in a field sampling survey.
Airborne asbestos concentrations were determined by personal, area, and high-
volume air sampling before and during removal of asbestos from portions of
the ceiling of the Federal Aviation Administration (FAA) radar facility
garage at Bucks Harbor, Maine. Wet and dry removal methods using a truck-
mounted vacuum system owned and operated by a private contractor were
evaluated. Overall filtration efficiency and the filtration efficiency of
each of the three stages of the vacuum system filters were determined by
isokinetic sampling upstream and downstream of each stage. Asbestos emis-
sions during disassembly and disposal of the system were measured and
visually observed. Filter loading during air sampling was optimized using
the 6CA Fibrous Aerosol Monitor (FAM) which had previously been calibrated
in the laboratory. Based upon the results of the survey, several preliminary
recommendations and conclusions have been formulated.
1
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Four elements of the overall program were not completed. Quantitative
evaluation of asbestos losses during system disassembly was not made. The
vacuum hose was not decontaminated during the study. Disposal of asbestos
collected by the dry method of asbestos removal was not characterized, and
building interior and ambient asbestos concentrations were not measured after
asbestos removal. Numerous vacuum system malfunctions limited the amount
of ceiling material removed and prevented complete characterization of system
performance. These malfunctions, coupled with the fact that the removal
process was more time consuming than anticipated, led to the decision by
the FAA to temporarily halt the removal operation. Thus, asbestos removal
from the garage area was never finished and post-removal samples could not
be taken.
IIT Research Institute's contract with the U.S. Environmental Protection
Agency was restricted to the monitoring of the asbestos removal operations.
Included were personal, area, and environmental sampling and analysis as
well as visual observations of the protocols used for the removal and dis-
posal of the asbestos-containing material. Site preparation, safety, support
equipment, and coordination of the various contractors were the responsi-
bility of the FAA and their consultant, Environmental Technology, Inc., West
Hartford, CT. The actual removal operations were performed by Diversified
Vacuum Systems, Newark, NJ using laborers from a local labor pool. Ultimate
decision making authority rested with the FAA.
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SECTION 2
CONCLUSIONS V
1. Fiber concentrations down wind of the vacuum system were less than
0.1 f/cm3.
2. Fiber concentrations in the work area during wet asbestos removal were
less than 1.5 f/cm3.
3. Fiber concentrations in the work area during dry asbestos removal were
less than 0.15 f/cm3.
4. The shower room and other non-work areas of the building were not con-
taminated with asbestos during wet or dry removal procedures.
5. The .asbestos removal and collection vacuum system performed with an
estimated minimum collection efficiency of 99.997%.
6. Visible emissions of the collected asbestos material were observed
during the dumping operations at the waste disposal site. Thorough
wetting of the material may alleviate these emissions.
7. Asbestos fiber concentrations during disposal were less than 0.2 f/cm3
as measured by personal and area samplers.
8. Sources of personal exposure to or environmental emission of asbestos
during operation disassembly and disposal were:" water which leaked
from the door of the collection reservoir after vacuum shut-off;
disassembly of the vacuum hose from the collection reservoir; contamina-
tion of the truck, exterior body and frame during disposal; and water
spray from the truck body during decontamination after disposal.
9. The Fibrous Aerosol Monitor determines amosite fiber concentrations
in agreement with NIOSH P&CAM 239.
10. Chrysotile fiber concentrations determined by the Fibrous Aerosol
Monitor substantially underestimate those determined by NIOSH P&CAM 239.
11. The Fibrous Aerosol Monitor was a useful monitoring tool in identifying
activities that were sources of asbestos emission, e.g., the exiting
of the operator to service the vacuum system.
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SECTION 3
RECOMMENDATIONS
1. Further work is needed to develop a protocol for testing non-approved
asbestos removal methods.
2. Evaluation criteria must be formulated so that environmentally acceptable
asbestos removal methods may be characterized and made subject to EPA
approval.
3. A definitive study is required to investigate the disagreement between
fiber concentrations reported by the Fibrous Aerosol Monitor (FAM) and
those determined by NIOSH P&CAM 239, especially insofar as fiber
diameter effects occur.
4. A field sampling survey should be conducted to characterize the diameter
distributions of environmental asbestos and to determine the impact of
variable asbestos fiber diameter on concentrations determined using the
FAM.
5. Field calibration techniques should be investigated to facilitate adjust-
ment of the FAM versus variable asbestos fiber types.
6. Tools to facilitate asbestos removal must be developed.
7. Methods must be developed to prevent in-line freezing of amended water
used in spray-equipped vacuum trucks. Methods of unclogging filters or
preventing filter freeze-up need to be developed.
8. A removable control and monitor panel interconnected with the vacuum
system by an umbilical cable should be provided to minimize the need
for the operator to exit the work area.
9. Alternate methods of asbestos disposal must be identified; on-board
bagging of dry asbestos and slurry disposal by dumping or pumping
appear worthy of investigation.
10. Decontamination techniques for equipment used in wet and dry removal
must be fully investigated.
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SECTION 4
BACKGROUND
SITE DESCRIPTION
The FAA radar facility at Bucks Harbor, Maine—a nearly windowless five-
story structure approximately 150 feet square—stands on an isolated hilltop
where contamination from background asbestos fibers should be negligible.
The ceilings of the fourth floor and the garage are coated with asbestos,
presumably for noise abatement. As can be seen from Figure 1, the garage
ceiling is in a deteriorated state. The fourth floor houses most of the
functional electronic equipment used for air traffic control, equipment
that must be continuously operational. In fact, the area is staffed contin-
uously.
The need to update and service the electronic equipment has periodically
brought FAA personnel in contact with the friable ceiling, further aggravat-
ing its poor condition. FAA recognition of the potential health hazard posed
by the release of asbestos into the workplace motivated the removal of the
ceiling.
The sensitive nature of the electronic equipment, which is intolerant
of extreme fluctuations of humidity and temperature, made wet removal an
unacceptable method. The need to man and operate the electronic equipment
on a continuous basis eliminated the possibility of using conventional .dry
removal, which releases significant amounts of asbestos fibers into the air.
The garage, however, is a relatively open area containing few pieces
of sensitive equipment, as illustrated in Figure 2, and FAA personnel have
a limited need to be there. The garage was therefore selected for trial
wet and dry asbestos removal using the vacuum system. If this trial proved
successful, it was planned to then remove the asbestos from the fourth floor
ceiling.
SITE PREPARATION
The site was prepared in general accordance with EPA guidelines1 to
prevent emission of asbestos to nonwork areas in the building and outdoors.
That is, plastic enclosed framing was constructed to provide removal
1 Sawyer, R.N. and C.M. Spooner. Asbestos-Containing Materials in School
Buildings: A Guidance Document, Part 2. EPA C00090. U.S. Environmental
Protection Agency, Washington, D.C., 1979. 133pp.
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Figure 1. Photograph of delaminating ceiling
material in FAA radar facility.
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Vacuum Truck
Air Conditioning-!
Equipment
CD
CD
Electrical Panels
Baffles
Shower
Stairwell
E
3—C
Elev,
Cable Chase .
Boiler
Room
Garage Area—tApproX. 2090 m2
Girage Volune - Approx. 890£) n3
Utility Room
Main Entry
and Change Room
Figure 2. Garage area at FAA Radar Facility.
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personnel access to the garage area through a double-baffled anteroom,
shower room, and change room. The areas, described in Section 5, where the
removal of asbestos was actually performed were not enclosed with framing
due to physical and time constraints. The stairwell door to the work area
was canopied with a single baffle to permit make-up air to enter the room
while the vacuum system was operating. The roll door on the northeast siae
of the building was draped on the inside, allowing a plastic-baffled opening
for passing power cords and the hose from the vacuum truck. .This opening
was also used periodically by the vacuum system operator in order to monitor
system functions. Air conditioning vents, doorways, and the elevator door
were sealed to prevent contamination. The walls and nonelectrical structures
were not draped with plastic, since they were already heavily dust laden
and would require decontamination as part of the cleaning operation.
SAFETY CONSIDERATIONS
Occupational Safety and Health Administration (OSHA) regulations pertain-
ing to asbestos removal or stripping were observed. Specifically, personnel
whose presence was required in the work area were briefed on the potential
dangers of exposure to asbestos and instructed as to the proper use of all
safety equipment. Respiratory protective devices were required whenever ex-
posure limits were expected to be exceeded. Air purifying respirators were
used when asbestos concentrations of up to 10 times the exposure limit were
anticipated. Continuous flow, supplied air respirators (minimum flow 6 1pm)
were used when asbestos concentrations of up to 100 times the exposure limit
were anticipated. Disposable Tyvec® coveralls with attached head coverings
and boots were worn at all times by personnel in the work area. Caution
labels pertaining to "asbestos hazard" were posted at all points of access
to the building.
Prior to beginning the removal operation, the workers entered the change
area, Figure 2, where they donned clean coveralls and respirators. They then
proceeded to the utility room where they picked up additional equipment, such
as replacement tools. On leaving the work area, each worker brushed the gross
contamination from his coveralls, removed all clothing except the respirator,
and disposed of them in a suitable container. They then proceeded to the
shower; only when the worker was thoroughly wet was the respirator removed.
After showering, the worker dressed in fresh coveralls or street clothes.
VACUUM SYSTEM DESCRIPTION
A detailed description of the vacuum system and its mode of operation
is presented in Appendix A; only a summary will be provided here.
The truck-mounted vacuum system, provided by Diversified Vacuum Systems,
Inc., consisted of a sprayer-equipped receiving chamber, three stages of
exhaust filtration, and vacuum blower, as illustrated in Figure 3. The intake
of the vacuum was located on the top center of the receiving chamber and
was connected to the work area with a 15.2 cm i.d. ribbed plastic hose. The
intake pipe extended about 20 cm into the chamber beyond the face of the primary
filters to aid particle sedimentation. Air was exhausted through diffusers
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Silencer
Ribbed Intake Hose
Slip-Joint for Dumping
Cylindrical Secondary
Filters (2)
7\/V\
Intake
Primary Filters
Diffuser Screens
Spray Nozzles
Discharge
Roots Blower
Final HEPA Filters (2)
A
q
r \ = Locations of Sampling Probes
« l
D
Clean-oat
Door
Hydraulic Cylinder for Dumping
Figure 3. Schematic of truck-mounted vacuum system.
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and primary filters located in the ceiling of the receiving chamber, through
a gooseneck at the top front of the chamber, and through an 0-ring sealed
joint (used during the dumping operation). The air then passed through the
secondary filter set, roots blower, silencer, and a pair of semes-mounted
HEPA filters, leaving the truck bed through a 15.2 cm i.d. plenum. With
the exception of the gooseneck joint, all pipe connections were welded or
bolted.
During normal operation the vacuum system is controlled automatically
and does not require the attention of an operator. The roots blower is under
direct drive from the truck engine. Whenever the differential pressure across
the primary filter exceeds a preset value, the engine speed is reduced to
idle, slowing the blower. Alternatively, whenever the differential pressure
falls, the engine speed increases, simultaneously increasing blower speed.
Should the primary filters become clogged, as indicated by too high
a differential pressure, the engine speed would be reduced to idle and high-
pressure air would be injected behind the primary filters to back-flush them.
The vacuum receiving chamber was arranged so that a door at the back
of the chamber could be opened and the entire vacuum chamber could be canted
backward by a hydraulic ram to facilitate dumping of the collected asbestos.
The points sampled isokinetically to characterize the filtration effi-
ciency of the system are indicated in Figure 3. Sampling points were center
line at least eight diameters downstream and two diameters upstream of all
flow disturbances. Sampling point A was through the wall of the intake hose
before the receiving chamber; point B was between the primary and secondary
filters; point C was located downstream of the silencer and blower between
the secondary and tertiary (HEPA) filters; and point D was located in the
exhaust plenum downstream of the HEPA filters.
WET AND DRY REMOVAL METHODS
Dry removal of untreated friable asbestos material is generally not
recommended, but where necessary can be accomplished with specific EPA
approval.2 As shown in Table 1, dry removal can result in airborne fiber
counts that can exceed 100 f/cm3.3 Asbestos removal following application
of water without a wetting agent usually gives higher fiber counts because
of the poor wettafaility and reduced penetration of the ceiling material. The
addition of a wetting agent to water, or amended water, improves the wett-
ability and penetration. Correctly applied amended water wet removal methods,
however, generally result in significantly lower fiber concentrationSo
2 IBID, p.II-4-1.
3 IBID, p.II-2-3.
10
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TABLE 1. AIRBORNE FIBER CONCENTRATIONS
DURING WET AND DRY REMOVAL METHODS3
Removal
Method
Dry
Dry
Wet
Wet
Wet
Wet
Concentration*
f/cm3
82.2
>100
23.1
2.8
18.4
0.5
Number of
Sampl es
11
N.A
6
56
12
5
No wetting agent used; heavy
water run-off
Amended water treatment
Amended water treatment;
water inadequately applied;
dry patches seen
Amended water treatment;
cementitious material delami-
nates in sheets; chunks intact
Fiber concentrations were determined by NIOSH standard microscope methods.
IBID, p. II-2-3.
11
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SECTION 5s
METHODS
Four techniques of asbestos removal were characterized during the field
sampling survey. Background samples of air and environmental surfaces were
obtained before removing any asbestos. Asbestos emissions during operation,
disassembly, and dumping were observed. Sampling was expedited by using
the FAM which had previously been laboratory calibrated against the NIOSH
microscope methods. The following sections detail the removal methods
characterized.
BACKGROUND SAMPLING
Before removing the asbestos, background samples were taken to provide
a base of comparison for the data collected on various removal techniques.
The background samples taken from points indicated in Figure 4 consisted
of five area samples collected at various indoor locations (one in a second
floor hallway not shown in Figure 4, one in the stairwell landing between
the first and second floor, and three inside the garage) and two bulk samples
removed from the ceiling. High-volume air samples were collected upwind
and downwind on the northeast side of the building where the vacuum system
was to be parked.
Floor and wall wipes were taken in the garage. The wipes were obtained
by vacuuming a designated area, usually one foot square, onto a Mi Hi pore'^AA
cellulose acetate membrane filter mounted in a preweighed, open-faced, 37
mm cassette with suction provided by a vacuum pump.
WET REMOVAL METHODS
Wet Removal I
The asbestos-coated ceiling on the northern corner of the garage was
sprayed with amended water (Aquagrow from Aquatrols Corp. of America, Penn-
sauken, N.J.) from a distance of 3 to 4 feet using a portable garden pesti-
cide sprayer. The ceiling was further wetted by a stream of water from a
garden hose until the coating was thoroughly wet. The asbestos coating was
scraped directly into the 15,2 cm intake duct of the vacuum with 10.2 cm
putty knives. Three workers participated in the operation, each spending
approximately equal time scraping asbestos, holding the vacuum hose or wetting
down the ceiling, and policing fallen ceiling material from the floor area
below the work platform. The samplers were situated as indicated in
Figure 5.
12 <
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Upwind
D
Wind Direction
Downwind
D
T '
X = Area Sampler
D= High Volume Sampler
Figure 4. Background sampling locations.
13
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D Downwind
Wind Direction
D
Upwind
X = Area Sampler
D= High Volume Sampler
O= FAM
Figure 5. Sampling locations during Wet Removal I,
14
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Wet Removal II
The asbestos coating was wetted, as in Wet Removal I, and then was
scraped from the ceiling and allowed to fall to the floor. The third man
in the crew vacuumed the asbestos from the floor. Again, the workmen alter-
nated duties of scraping, vacuuming, and wetting, each spending approxi-
mately equal time on each activity. The samplers were located as indicated
in Figure 6.
DRY REMOVAL METHODS
Dry Removal I
During Dry Removal I, no water or amended water was applied to the ceil-
ing. The celling material was scraped using various tools and techniques
and deposited into the vacuum hose, either with or without a variety of noz-
zles. The following techniques and equipment were used during dry removal:
A. Asbestos was scraped from the ceiling by two men, each
using 10.2 cm wide paint scrapers; the ceiling materials
were deposited in chunks into a single 15.2 cm diameter
vacuum hose. In this technique, the scraper frees a
chunk of asbestos material large enough to be held
between the hand and the scraper. The material can be
bent to break it away from the ceiling. The resulting
chunk is placed into the vacuum by hand.
B. Asbestos was scraped by one man using a 10.2 cm paint
scraper; a second man caught the scrapings in a 38.1 cm
long, 20.3 cm wide, 15.2 cm deep rectangular box nozzle
attached to the end of the vacuum hose. As a variation,
scraping was accomplished by a pneumatically actuated
paint scraper; the second man still collected the
scrapings>
C. Asbestos was scraped by one man using the rectangular
box attached to the 15.2 cm vacuum hose.
D. A Y-adaptor was fitted to the end of the 15.2 cm vacuum
hose to which two 10.2 cm diameter hoses were attached.
Each workman scraped the ceiling using a 10,2 cm paint
scraper held in one hand and caught scrapings with the
10.2 cm vacuum hose held in the other hand. A scraper
and knife-equipped prismatic nozzle was used on one
10.2 cm hose during part of Dry Removal I.
15
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q
Downwind
Wind Direction
X = Area Sampler
O= FAM
O= High Volume Sampler
Figure 6. Sampling locations during Wet Removal II.
16
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Sampling locations during Dry Removal I are illustrated in Figure 7.
Dry Removal II
Dry Removal II was a brief session of dry scraping the asbestos ceiling
and permitting the scraped material to drop to the floor. The vacuum system
was not used during this session. This test represents' a worst case method
of removal. Sampling locations are as indicated in Figure 8.
SYSTEM DISASSEMBLY AND ASBESTOS DISPOSAL
After wet asbestos removal was completed, the vacuum system was shut
off and partially disassembled for transport by truck to the disposal site.
Shutoff was accomplished by disengaging engine power from the roots blower
and allowing the vacuum system to come to atmospheric pressure. The 15.2 cm
vacuum hose was uncoupled from the top-center entry port on the receiving
chamber.
The disposal site, located in a swampy area of the Machiasport, Maine
dump, was a water-filled pit approximately 3 m square and more than 1 m deep.
The texture of the ground prevented the vacuum truck backing to the pit and
dumping the asbestos load directly into the pit. Therefore, the load was
dumped in front of the pit and pushed into the pit by a small bulldozer.
The asbestos load was released by unlatching the 2.4 m x 0.8 m door of the
reservoir and then tipping the reservoir by means of a hydraulic ram. The
door, hinged at the top, canted out of the way as the asbestos spilled out.
Figure 9 illustrates the truck in the dump position. After dumping, the
driver flushed the asbestos-contaminated reservoir and outside surfaces of
the truck with a pressurized water spray. Sampling locations are indicated
in Figure 10.
17
-------
n
Downwind
X = Area Sampler
O= FAM
D= High Volume Sampler
Figure 7. Sampling locations during Dry Removal I.
18
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X = Area Sampler
O = FAM
Figure 8. Sampling locations during Dry Removal II.
19
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Figure 9. Photo of truck in dumping position.
20
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Upwind
Sampling
Point
30.5 m
Disposal Pit
6.1 m
Downwind
Sampling
Point
Vacuum
Truck
Figure 10. .Sampling locations during asbestos disposal
21
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SECTION 6
SAMPLING AND ANALYSIS PROCEDURES
SAMPLING
Vacuum Truck Sampling
Prior to each asbestos removal, the vacuum system was instrumented with
0.18 cm i.d. probes connected to 37 mm diameter, 0.45 ym pore size cellulose
acetate membrane filters mounted in tared filter cassettes. Suction was
provided by rotary vane vacuum pumps with flow controlled by 4.9 1pm critical
orifices. The probes were inserted into the ribbed intake hose, the suction
header just ahead of the secondary filter set, in between the silencer and
the HEPA filter (high efficiency particulate air), and in the HEPA filter
discharge hose, as illustrated in Figure 3.
The flow rate through the sampling train was checked with a calibrated
rotameter and determined to be 4.0 1pm.
Since difficulty was anticipated while sampling in the ribbed vacuum
hose, an alternate procedure was used to estimate the mass input to the vacuum
system. Unit samples of wet and dry asbestos were removed from measured
areas of the ceiling in the work area. These were dried and weighed in the
laboratory to determine the mass of ceiling coating removed per unit area.
After sampling was completed during a removal method, the area of ceiling
cleaned was measured to estimate the mass input during each sampling period.
Filter cassettes were dried to constant weight in a dessicator. Mass accu-
mulated during sampling was used to determine filtration efficiency of the
vacuum system on a mass basis.
Bulk Samples and Area Wipes
Two bulk samples of the friable ceiling material were taken for subse-
quent characterization by polarized light microscopy and x-ray diffraction.
These procedures are detailed in Appendix B. The composition of area wipes
was determined by polarized light microscopy.
Personal, Area, and High-Volume Sampling
Personal samples were collected on a 0.8 urn pore size cellulose acetate
membrane filters mounted in open-faced 37 mm diameter cassettes using MSA
Model G personal sampling pumps at 1.7 1pm. The sample pumps were attached
to the coveralls of the workers by means of duct tape straps around the waist
22
-------
and over the shoulders, as shown in Figure 11. The cassette filter holders
were attached as close to the breathing zone as possible. Personal samples
were taken to assess the extent of individual exposure attributable to each
method of asbestos removal.
Area samples were taken on 0.8 pro pore size 37 mm diameter cellulose
acetate filters mounted in open cassettes at approximately 2.0 1pm. Flow was
measured at the beginning and end of each test period by means of a cali-
brated rotameter. Area samples were taken 152 cm above floor level to deter-
mine the extent of contamination at that particular location.
High-volume air samples were collected on 0.8 pm pore size 20.3 cm x
25.4 cellulose acetate and 0.45 ym pore size 20.3 cm x 25.4 cm polycarbonate
membrane filters upwind and downwind of the site. The high-volume samplers
had previously been calibrated using a universal high-volume calibrator.
Sampling flow rates were measured at the beginning and end of each sampling
period. High-volume samples were taken to assess contamination to the
environment attributable to the asbestos removal operation.
Fibrous aerosol concentration in the removal area and the high-volume samples
collected on cellulose acetate membrane filters were analyzed by phase-
contrast microscopy as discussed below. Electron microscopy was used to
evaluate fibers collected on high-volume polycarbonate membrane filters and
to confirm identification of asbestos fibers counted by phase-contrast
microscopy in selected area samples. Electron microscopy methods are
described below.
ANALYSIS
Phase-Contract Microscopy
Phase-contrast microscopy (PCM) was used to assess airborne fiber con-
centrations in accordance with NIOSH Analytical Method P&CAM 239.4
A portion of the filter—from the midsection to the outer edge—was
mounted on a glass slide and cleared in a refractive index fluid, using
a technique that is a variation of P&CAM 239.5 This method allows the slides
to be retained for re-examination and comparison for a longer period of time
than the standard method. A description of this technique is given in Appen-
dix C.
Leidel, N.A., S.6. Bayer, R.D. Zumwalde, and K.A. Busch. USPHS/NIOSH
Membrane Filter Method for Evaluating Airborne Asbestos Fibers. DHEW
(NIOSH) No. 79-127. National Institute of Occupational Safety and Health,
Cincinnati, Ohio, 1979. 21pp.
Millipore Corporation Technical Brief: Procedure for Rendering MF-
Millipore and Celotate Membrane Filters Transparent. Bedford, Massachu-
setts, 1975. 2pp.
23
-------
Figure 11. Photo of personal sampling pump attached to worker.
24
-------
The fiber concentration on each filter was analyzed using phase-contrast
microscopy and observing counting rules recommended by NIOSH.
Polarized Light Microscopy
Polarized light microscopy (PLM) was used to identify the composition
of the bulk samples and floor wipes and determine the type and percentage
of materials present. A Zeiss light microscope with rotary stage, polarizer
and analyzer, multiple objectives, and immersion oils with several different
indices of refraction were used to make the identifications. In some cases,
specific fibers were teased from the bulk specimen and remounted for further
study. A detailed description of this method is given in Appendix C.
Electron Microscopy
Electron microscopy for asbestos analysis was conducted in accordance
with the EPA's provisional methodology.6 A grid opening was selected at
random for critical examination at a magnification of 20,OOOX. The fibers
observed in this opening were counted and measured. Each fiber was examined
by selected area electron diffraction; the resulting pattern was used to
identify the fiber as either serpentine, amphibole, not asbestos, or no pat-
tern. In some cases, fiber identity was further confirmed using energy dis-
persive x-ray analysis for trace metals content.
X-Ray Diffraction
The bulk sample of ceiling material was separated into two fractions:
the outer layer (termed "white") and the inner layer (termed "brown"). Both
layers were analyzed by x-ray diffraction in two states: one was a nearly
raw state after minimal crushing; the other was produced by grinding in a
Wig-L-Bug (Crescent Dental Manufacturing Company). Four different samples
were analyzed: white-raw, white-ground, brown-raw, and brown-ground. Each
of the four samples was packed into a standard sample holder until it was
flush with the plane of the holder. Pressure was applied to the two ground
forms so no material would be lost in the x-ray diffraction unit.
The diffraction pattern of the brown portion was measured over the range
5° to 75°. Thirty-five major lines were observed and used for identification.
An automated search of the JCPDS (Joint Committee on Powder Diffraction San-
dards) mineral file provided a list of candidate identifications which were
evaluated using chemical data and line-by-line comparisons. The diffraction
pattern of the "white" portion was also measured over the angular range of
5° to 75°. Twenty-two major lines were observed and used for identification.
A computer search of the JCPDS file was again used to generate a list of
matching patterns.
6 Samudra, A.V., C.F. Harwood, and J.D. Stockham. Electron Microscope
Measurement of Airborne Asbestos Concentrations: A Provisional Method-
ology Manual. EPA-600/2-77-178. U.S. Environmental Protection Agency,
Research Triangle Park, North Carolina, 1978. 57 pp.
25
-------
Fibrous Aerosol Monitor
A primary consi deration.for using the fibrous aeresol monitor (FAM) was
to obtain better defined evaluation of its design and use, provide a calibra-
tion, and monitor the asbestos removal activities. A brief description of
the FAM and its operating principles and procedures are included in Appen-
dix D. ,
Two well-character!zed asbestos samples were used to calibrate the FAM.
Table 2 summarizes the length and diameter distributions of the chrysotile
and amosite used; Table 3 summarizes manufacturer's suggested FAM operating
conditions for various fiber types. Chrysotile, a member of the serpentine
group of asbestos minerals, was selected for calibration because 95% of the
asbestos commercially consumed has been chrysotile; accordingly, it is more
likely to be encountered than any other asbestos form. Amosite, a commer-
cial name for South African amphibole asbestiforms usually of the cummingtonite-
grunerite type, was selected because the manufacturer calibrates the FAM
in the factory using amosite. This provided a reference check of FAM per-
formance.
Calibration asbestos aerosols were generated by pneumatically spraying
asbestos slurries into a stirred 14.5 m3 chamber. Samples were collected
for 30 min. from adjacent points using the FAM and open-faced filters. Filter
sampling and analysis was done in accordance with NIOSH P&CAM 239 using the
modified filter clearing procedure.
i
The calibrated FAM was then used to optimize filter loading for area
sampling, to identify sources-of fiber contamination during removal, and
to assist the removal workforce in optimizing removal techniques.
26
-------
TABLE 2. STATISTICS OF THE ASBESTOS MATERIALS USED FOR FAM CALIBRATION
ro
Intermediate Range
Mean
Geo. Standard Deviation*
Minimum
Maximum
Median
10th Percenti le
20th Percenti le
30th Percenti le
40th Percentile
50th Percentile
60th Percentile
70th Percentile
80th Percentile
90th Percentile
95th Percentile
99th Percentile
99.9th Percentile
Length
(ym)
1.25
6.44
0.10
783.39
0.82
0.32
0.40
0.50
0.65
0.82
1.02
1.27
1.61
2.15
2.54
3.07
76.9
Diameter
(ym)
0.11
0.17
0.02
11.55
0.09
0.04
0.06
0.06
0.07
0.09
0.10
0.12
0.14
0.20
0.21
0.32
0.69
Chrysotile
Aspect Ratio
11.48
9.41
3.00
340.65
8.44
4.28
5.28
6.21
7.17
8.44
9.91
12.18
15.70
22.51
—
—
—
>
Amosite
Length
(ym)
12.54
28.59
0.85
994.79
4.37 :
1.73
2.31
2.62
3.01
4.37
5.84
7.58
12.92
31.63
-«
Diameter
(ym)
1.09
1.13
0.06
12.36
0.72
0.27
0.34"
0.43
0.54
0.72
0.85
1.08
1.47
2.90
—
—
Aspect Ratio
10.12
11.75
3.00
227.94
6.42
3.51
4.09
4.70
5.56
6.42
7.59
9.39
12.43
20.48
—
—
—
* unitless
-------
TABLE 3. RECOMMENDED FAM CONTROL SETTINGS FOR KNOWN ASBESTIFORM FIBER TYPES7
r\>
oo
Fiber Types
Amos i te
Crociddlite
Chrysotile
Chrysotile
(alternate)
Ratio
Setting
5.0
5.0
5.0
Amplitude
Setting
0.5
0.5
0.1
see
comments
Discrimination
Mode Setting
Ratio plus amplitude
Ratio plus amplitude
Ratio plus amplitude
Amp! i tude
Comments
Factory calibrated for these
these conditions
See alternate below
Ratio sensing disabled.
Determine correct amplitude,
setting by comparison with
microscope filter count.
7 6CA Environmental Instruments, GCA Fibrous Aerosol Monitor Model FAM-1 User's Manual. FAM-79-100.
Bedford, Massachusetts, 1979. 69pp.
-------
SECTION 7
RESULTS AND DISCUSSION
Background contamination levels and the analysis of bulk samples are
presented first to identify baseline levels and the ceiling materials of
interest. Each of the three major objectives is then presented: personal,
area, and environmental exposures to asbestos resulting from the filtration
efficiency of the removal system, system disassembly, and asbestos disposal.
Additional miscellaneous results and observations are presented last, includ-
ing comments on the fibrous aerosol monitor.
BACKGROUND SAMPLING AND BULK MATERIAL ANALYSIS
Bulk Material Analysis
The garage ceiling was coated relatively uniformly with two layers of
asbestos-containing material. The total thickness of the coating was about
3 cm. The cqating consisted of an outer white layer and an underlying brown
layer. Paint had been applied to the surface of the white layer. Large
areas of the outer layer had delaminated, as evident in Figure 1. Two sam-
ples of ceiling material were submitted for analysis of the bulk material
and found to be identical. Material analysis by PLM (summarized in Table 4)
indicated the white layer contained 49% chrysotile and 18% amosite; the brown
layer contained 11% chrysotile and 56% amosite.
X-ray diffraction analysis confirmed the identifications provided by
PLM. The diffraction pattern of the white portion, measured over the
angular range of 5° to 75°, contained twenty-two major lines. The three
major components—chrysotile (monoclinic), calcite, and aragonite—accounted
for 20 of the observed lines. The patterns of the "ground" and "raw"
samples were essentially alike, except that the raw white sample showed strong
evidence of preferred orientation of the chrysotile crystals. This is common
with chrysotile.
The diffraction pattern of the brown portions was measured over the
range 5° to 75°. Thirty-five major lines were used for identification. Two
major components—calcite and grunerite—accounted for 23 of the lines. Cum-
mingtonite, whose pattern is very similar to grunerite, may be present. Man-
ganese was detected in the sample using x-ray fluorescence. A minor amount
of quartz was also present and accounted for four additional lines.
Background Sample Analysis
Table 5 summarizes the concentrations of background airborne fibers
29
-------
TABLE 4. BULK MATERIAL ANALYSIS OF CEILING MATERIAL BY PLM
Surface Underlying
Layer Layer
COLOR: White Brown
COMPOSITION:
Chrysotile 49% 11%
Amosite 18% 56%
(fibrous grunerite contaminated
with anthophyllite)
Plaster, Mortar, Iron Oxide,
Hornblende, and other trace components 33% 33%
30
-------
TABLE 5. BACKGROUND FIBER CONCENTRATIONS
Location
Outdoor: Upwind
H
Downwind
ii
Indoor: Hallway
4th Floor
Stairwell
Garage
H
H
Sample
Sampler Type Time
High-Volume 420 min.
H n
High -Volume 420 min.
n n
Area, 2.0 1pm 240 min.
120 min.
240 min.
240 min.
240 min.
32 min.
Analytical
Method*
PCM
TEM
PCM
TEM
PCM
PCM
PCM
PCM
PCM
PCM
Fiber
Concentration
(f/cm3)
<0.'005
o.oqo
<0.005
0.000
<0.005
0.020
0.014
0.029
" 0.009
<0.005
PCM is NIOSH Phase Contrast optical microscopy, reference 4.
TEM is EPA provisional electron microscopy method, reference 7.
-------
sampled by area and high-volume samplers within and around the FAA facility
before asbestos removal operations. Outdoor fiber concentrations before
asbestos removal were lower than the resolution limit for phase-contrast
microscopy; no fibers were observed by electron microscopy. The time- g
weighted average indoor concentration for all samples was 0.014 fibers/cm .
Table 6 summarizes environmental surface contamination as revealed by
polarized light microscopy of surface wipes. Asbestos was a major component
only in the garage vertical I-beam samples. Amphibole (grunerite) predomi-
nated in the wipe samples even though it is a minor component of the outer
ceiling layer. Further, most of the chrysotile was coated or encapsulated
with paint.
PERSONAL, AREA, AND ENVIRONMENTAL ASBESTOS CONCENTRATIONS
Personal exposure to airborne fibers was determined by open-faced filter
sampling and the NIOSH standard microscope method during each method of
asbestos removal (Table 7). Time-weighted average personal exposure, in f/cm33
was greatest during Wet Removal II, in which the asbestos ceiling material
dropped to the floor and then was vacuumed. Some drying and resuspension
of asbestos may have occurred during this mode of operation to elevate the
fiber concentration. Personal sampler fiber concentrations observed for
Dry Removal I, in which dry asbestos ceiling material was deposited directly
into the vacuum hose, are surprisingly low compared with typical values for
other dry removal techniques.
Indoor and outdoor area concentrations attributable to each removal
method were determined by phase-contrast microscopy or the TEM provisional
method (Table 8). As with personal samples, the highest fiber concentrations
in the work area were collected during Wet Removal II. The highest concen-
tration was 1.4 f/cm3. The various techniques utilized during Dry Removal
I did not last for a period of time long enough to obtain accurate measure-
ments. However, the FAN detected slight changes in fiber concentration.
The partitioning of the work area successfully minimized contamination
of the other areas within the FAA facility. The highest non-work area con-
centration was 0.33 f/cm3, found in the shower during Wet Removal II. Small,
but measurable, outdoor fiber concentrations were recorded; the maximum con-
centration was 0.02 f/cm3.
The evaluation of outdoor fiber concentrations is difficult for several
reasons. Some cross-contamination of upwind and downwind samples probably
resulted from the irregular wind directions and complex air flow patterns
around the radar facility. In addition, all of the fibers found on the high-
volume filters may not have necessarily come from the vacuum truck during
removal. The operator periodically left the work area through the roll door
access opening to service the vacuum system. The FAM was especially useful
here, as it detected the fibers shed from his work clothes during these ser-
vice excursions. Finally, some contamination undoubtedly occurred during
disassembly (discussed below).
32
-------
TABLE 6. ANALYSIS OF AREA WIPE SAMPLES BY POLARIZED LIGHT MICROSCOPE
Surface load, g/ft2
Primary Components
>253
Major Components
5 to 25%
Minor Components
0.5 to 5%
Trace Components
<0.5%
Garage Floor
Near A/C Pumps
0.130
Quartz
Textile fibers
Paper fibers
Micas
Paint spheres
Paint flakes
Iron oxides
Amphibole asbestos
Chrysofile asbestos
Metal fragments
Clay
Humus
Carbonates
Wood fibers
Cement
Partial combustion
products
Aluminum oxides
Fiberglass
Rubber tire fragments
Garage Floor
Near Boiler Room
0.073
Quartz
Paint flakes
Paint spheres
Carbonates
Plaster
Mortar
Partial combustion
products
Wood fibers
Iron oxides
Hornblende
Iron silicates
Mica
Paper fibers
Textile fibers
Clays
Humus
Metal flakes
Amphibole asbestos
Chrysot lie asbestos
Location
Top Surface of
Air Conditioner
0.012
Quartz
Paper fibers
Textile fibers
Partial combustion
products
Paint flakes
Paint spheres
Plaster
Mortar
Hornblende
Other non-silicates
Amphibole asbestos
Mica
Iron oxides
Carbonates
Clays
Humus
Vermiculite
Metal flakes
Wood fibers
Other minerals
Chrysotile asbestos
Fiberglass (organic
Outer Wall of Garage
(1.5 m level)
0.006
Plaster
Mortar
Quartz
Wood Fibers
Paint spheres
Paint flakes
Metal fragments
Iron oxides
Aluminum oxides
Paper fibers
Textile fibers
Micas
Hornblende
Iron silicates
Carbonates
Partial combustion
products
Cement
Clays
Humus
Amphibole asbestos
Chrysotile asbestos
Vertical Surface of
Ceiling Support
0.004
Paper fibers
Wood fibers
Amphibole asbestos
Plaster
Paint flakes
Paint spheres
Textile fibers
Quartz
Micas
Chrysotile asbestos
Iron oxides
Metal flakes
Partial combustion
products
Clays
Humus
Asphaltic matter
Fiberglass
Rubber tire fragments
Vehicle exhaust
Plant parts
Insect parts
Starch
Rodent hairs
Human hairs
Skin flakes
Grinding abrasives
(silicon carbide)
Diatoms
Fiberglass
(organic bound)
Grinding abrasives
(silicon carbide)
Plant parts
Insect parts
Pollen
Spores
Rubber tire fragments
Vehicle exhaust
Human hair
resin coat)
Insect parts
Plant parts
Pollens
Spores
Rodent hair
Skin flakes
Rubber tire fragments
Vehicle exhaust
Human hair
Fiberglass
(organic bound)
Grinding abrasives
(silicon carbide)
Pollens
Spores
Plant parts
Insect parts
Human hair
Rodent hair
Rubber tire fragments
Vehicle exhaust
Insect parts
Pollens
Spores
Plant tissue
Skin flakes
Human hair
Plant parts
-------
TABLE 7. PERSONNEL EXPOSURE DURING ASBESTOS REMOVAL
Removal
Method
Sampler #24
Sampler #25
Sampler #82
TIME WEIGHTED
AVERAGE
Wet I
time.min.
185
35
185
41
186
35
Wet II
f/cm3 time,min. f/on3
4.16
1.79 40 34.47
3.77 43 9.10
1.07
1.12 46 4.06
1.11
2.73 15.17
Dry I
time,min. f/cm3
22 2.23
81 1.30
86 1.12
22 2.57
1.46
Exposure was determined by the NIOSH standard method.
34
-------
TABLE 8. INDOOR AND OUTDOOR AREA CONCENTRATIONS DURING ASBESTOS REMOVAL OPERATIONS
CO
en
Removal Method Wet I
Time,
min.
LOCATION:
Outdoor: Upwind 375
Downwind 375
Indoor: Hallway 372
Stairwell 374
Shower 253
Garage 185
119
120
Cone.,
f/cm3
0.02 (TEM)
0.01 (TEM)
0.01
<0.005
0.185
0.025
0.95
0.76
Wet II
Time,
min.
—
—
243
245
250
255
255
Cone. ,
f/cm3
—
—
0.005
<0.005
0.326
1.40
1.27
Time,
min.
330
330
333
363
281
342
342
Dry I Dry II
Cone. , Time, Cone. ,
f/cm3 min. f/cm3
0.007 (TEM)
<0.005
0.007 (TEM)
0.013
0.008
0.046
0.12 90 1.49
0.09
All concentrations were determined by phase-contrast microscopy or by the TEM provisional method for
Dry Removal II which was determined by the FAM.
-------
VACUUM SYSTEM COLLECTION EFFICIENCY
The collection efficiency of the vacuum system was determined on a mass
basis using the following technique. The mass input to the vacuum was esti-
mated by obtaining the dry weight of friable ceiling material removed from a
known surface area of ceiling and then computing the total mass removed by
estimating the area of ceiling cleaned. The mass downstream of each filter
element was obtained by differential mass accumulated on the membrane filters
collecting through isokinetic sampling probes. The HEPA filter discharge
was additionally monitored by the FAM and in Dry Removal I, by adjacent area
sampling.
Mass input and mass accumulation after each stage of filtration was
measured for each of the three removal methods employing the vacuum system
(Table 9). The mass input term is probably correct within ±25%. The mass
input term was measured by estimating the ceiling area cleaned during each
method. The filtration efficiency of the system exceeded 99.99% on a mass
basis. The HEPA discharge of 0.02 ppm by weight indicates that during oper-
ation the vacuum system is unlikely to be a significant source of environ-
mental contamination.
TABLE 9. VACUUM SYSTEM FILTRATION EFFICIENCY
Filter Discharge Values
Removal
Method
Mass in
kg
Primary
mg
Secondary
mg
HEPA
mg
Wet I 31 ± 8 2.4 ± 0.2 1.9 ± 0.2 0.7 ± 0.2
Wet II 61 ± 15 13.6 ± 0.2 1.2 ± 0.2 0.4 ± 0.2
Dry I 47 ± 12 6.3 ± 0.2 105.9 ± 0.2 0.7 ± 0.2
36
-------
WET VERSUS DRY REMOVAL
Personal, area, and ambient concentrations of asbestos fibers measured
during Wet Removal methods I and II in this study were comparable to those
previously summarized in Table i. That is, during Wet Removal I, personal
exposures averaged 2.7 f/cm3, work area concentrations averaged 0.5 f/cm3,
and ambient concentrations were less than 0.1 f/cm3. During Wet Removal II,
personal exposures averaged 15.2 f/cm3, work area concentrations averaged
1.3 f/cm3, and ambient concentrations were again less than 0.1 f/cm3. Other
studies measured asbestos concentrations over the range 0.5 to 23.1 f/cm3
during wet removal.
By way of comparison, during dry removal with the vacuum system, per-
sonal exposures averaged 1.5 f/cm3, work area concentrations averaged
0.1 f/cm , and ambient air concentrations were again less than 0.1 f/cm3.
As measured in this study, through the utilization of a properly filtered
vacuum system, asbestos can be removed dry from building interior surfaces
with airborne fiber concentrations comparable to those observed during stan-
dard Wet Removal procedures.
SYSTEM DISASSEMBLY AND ASBESTOS DISPOSAL
System disassembly and asbestos disposal are the two activities most
likely to release significant amounts of asbestos into the environment. After
the vacuum was shut off, accumulated water in the receiving chamber poured
out of the receiving chamber door, leaving a foamy puddle on the pavement
beneath the truck. Since the surfaces of the door gasket and mating flange
were smooth and clean, leakage was evidently caused by slight warpage in
the door and insufficient clamping force.
After the vacuum was shut off, the vacuum hose was uncoupled from the
receiving chamber pipe by the operator and soggy asbestos ceiling material
was violently spewed out by the force of the uncoupling. Upon inspection,
the interior of the vacuum hose revealed significant asbestos contamination.
The amount of asbestos contamination was probably increased by the presence
of water from the wet removal tests. Dry asbestos residue inside a dry hose
would probably be significantly less, though this has not been formally eval-
uated.
The vacuum truck is shown in the dumping position during asbestos dis-
posal in Figure 9. The sources of airborne asbestos during dumping are numer-
ous. A puff of aerosol was observed as the receiving chamber was canted.
After dumping, the back surfaces of the truck were significantly contaminated
with the asbestos-water slurry. The operator sprayed the truck with water
in an attempt to remove the asbestos contamination. A visible aerosol was
formed by theJet of water impinging on the truck surface; some asbestos
undoubtedly was carried away by this spraying procedure. A heavy mist of
water would probably produce less impingement aerosol and be more effective
in decontamination. A wipe sample was taken of the outside surface of the
door following decontamination. Analysis by PLM of-this sample revealed
asbestos fibers which had not been removed during washdown.
37
-------
The upwind area sampler indicated background asbestos concentrations
were below the lower detection limit for PCM; i.e., 0.005 f/cm3. In fact,
no fibers were visible on the filter. The personal exposure of the truck
operator was 0.067 f/cm3. The downwind sampler measured 0,116 f/cm3.
ADDITIONAL OBSERVATIONS
Table 10 summarizes the results of laboratory calibration of the FAM
using chrysotile and amosite aerosols. The percentage of statistical accu-
racy, % SA, for sampling is given by:8
±200
% SA =
/TO• t . n
where t = the sampling time in minutes
n = the fiber concentration determined by the NIOSH microscope
method in f/cm3.
The % SA cannot account for the shortfall in fiber counts for chrysotile
reported by the FAM. Instrumental malfunction is not indicated since amosite
concentrations are in reasonable agreement with those obtained by the NIOSH
method.
Operating procedures for chrysotile suggested by the manufacturers were
briefly evaluated. Operating the FAM in the amplitude-only mode with an
amplitude setting of 0.1 resulted in significant background counts for non-
fibrous aerosols. Further, fiber counts by FAM were not significantly dif-
ferent from background counts previously obtained in the test chamber with
no chrysotile; hence, this procedure is not recommended for ambient asbestos
sampling.
The FAM was used during asbestos removal to identify sources of con-
tamination that might otherwise escape notice. For example, in the last step
in site preparation, the few remaining boxes and equipment were removed
from the work area and stored temporarily near the shower. The FAM indicated
average fiber concentrations in this area of 0.1 f/cm3. By comparison, con-
centrations of 0.01 f/cm3 were obtained in the work area. The source of
the high fiber counts was identified as residue clinging to the boxes and
tracked into the shower when the boxes were transferred. After the area
was mopped down, FAM counts dropped to 0.01 f/cm3. The area sampler indi-
cated 0.185 f/cm3 prevailed in the shower.
Lilienfeld, P., and P.B. Elterman. Development and Fabrication of a
Prototype Fibrous Aerosol Monitor (FAM). EPA-600/7-77-147. U.S.
Environmental Protection Agency, Washington, D.C., 1977. 71pp.
38
-------
TABLE 10. COMPARATIVE NIOSH METHOD AND FAM FIBER CONCENTRATIONS"
Fiber Type
Chrysotile
Amos ite
FAM
Ser.No.
2003
2003
2003
2003
2003
2003
1004
2003
NIOSH method,
f/cm3
0.33
6,7
17.0
36.7
36.7
67
0.84
0.84
FAM
f/cm 3
0.00
1.20
2.6
1.98
3.9
0.36
0.53
1.08
Time,
min.
30
7
24
13
11
28
30
30
%SA
20%
9%
3%
3%
3%
1%
13%
13%
Notes
FAM gain 9
FAM gain 10
FAM operating conditions. Ratio 5. Amplitude 0.5. Ratio plus amplitude.
It was possible to identify specific activities which resulted in high
fiber concentrations by using the FAM during removal operations. During
dry removal with no vacuum the FAM immediately indicated that fiber concen-
trations were greater than those recommended when using the half-face
respirators wdrn by the work force; the workers left the area immediately.
Dropping the wet asbestos directly on the floor for subsequent vacuuming
during Wet Removal II gave 2.1 f/cm3, compared with 0.45 f/cm3 obtained during
Wet Removal I. These counts parallel results obtained by area samplers.
The lack of experience in asbestos removal on the part of the vacuum
system operator and work crew appears to have a direct bearing on the results
obtained in this study. For any removal technique utilized, fiber concen-
trations detected by the FAM were highest at the beginning. As the work
crew became more adept at the technique, fiber concentrations were observed
to decrease.
Several malfunctions occurred in the vacuum system which limited pro-
gress with asbestos removal. Most of these were associated with the spraying
system in the receiving chamber. The sprayers stopped functioning just before
the dumping operation. The water supply line for the sprayers froze overnight
and shattered the supply line rotameter.
The third malfunction apparently resulted from excessive water carry-
over from the receiving chamber into the filter elements. Water or ice
accumulation on the filter elements caused an excessive pressure drop in
the vacuum line; simultaneously, the vacuum available at the inlet hose was
inadequate to allow removal to continue. The automatic primary filter back-
flush system was unable to correct the problem, and the operator subsequently
shut the system down.
39
-------
APPENDIX A
VACUUM SYSTEM DESCRIPTION
40
-------
671 Frelinghuysen Avenue
Newark, N. J. 07114
(201) 242 7002
551 Post Road
Giounwidi, Conn. 06830
(203) 622-0493
October 5, 1979
Mr. John D. Stockham
Manager
Fine Particles Research
IIT Research Institute
10 West 35th Street
Chicago, Illinois 60616
Dear John,
As per our meeting on October 4, 1979. We will equip the test vehicle
with (4) four monitoring ports. Tentatively, the locations would be on
90° elbows with 1/4" female couplings installed at the centerlines, (subject
to your approval)-
As we have discussed, the line velocity will be a maximum of 20,000 F.P.M.
on the 4" air line to a maximum of 5000 F.P.M. on the 8" lines. Maximum
vacuum will be 200" H?0, (adjustable to a lower setting if necessary). The
line velocity is also adjustable if required. Keep us appraised of any par-
ticular requirement you may have, if possible we will comply. Within the
next few weeks we will forward a description of the equipment.
Very truly yours,
Robert De Mane
RD/kw
- A Complete Vacuum Service To Industry
41
-------
^versified
cuum
ysiem
Inc.
671 Frelinghuysen Avenue
Nowark, i\l. J. 071 M
(201) 242 /.002
!.H1 I'osl Uri-iiJ
(vn:;;'622'-d493
November 30, 1979
Mr. Roger Hancock
IIT Research Institute
10 West 35th Street
Chicago, Illinois 60616
Dear Roger,
Enclosed is a description of the Model AS-10 Vacuum Loader,
as modified for asbestos handling. Of particular importance in
the design of the unit is the filtration system and operating
parameters. The AS-10 is unique in that substantially all
filtration is handled directly in the main vacuum receiving
section. Asbestos dust and fiber is regenerated directly in this
chamber. This eliminates the necessity for a bag house and
separate dust conveying equipment. The primary problem with all
other trur?k mounted vacuum loaders has been: 1} Inability Lo
filter particulate sizes smaller than 1-2 micron. 2] No back up
or safety filtration to protect against bag failure. 3] No
positive sensing or electronic control system, and, 4] Bag house
contamination. Once the bag house has been contaminated by
asbestos, it is impossible to totally clean. The mechanism and
apparatus which conveys the dust from the bag house back to the
body is inaccessible, and cannot be cleaned. When this type of
truck is returned to regular vacuum service, it inevitably will
generate asbestos pollution.
The AS-10 is equipped with three major filtration sections.
Material enters the main vacuum receiving chamber. It is
diffused and baffled. Within this chamber there are multiple
filtration elements in a parallel configuration. All flow then
travels from the body section through a split flange with an "0"
ring seal, to the truck chassis. At the base of the split flange,
after the first 90° bend, we provided test port location No. 1.
Air flows through a straight section for approximately 3', at
this point, port No. 2 is located. From port No. 2, all air
passes through the second major filtration section. This consists
Df a compound element - a major and minor section. Air flows
straight for approximately 4 1/2', at the end of this run, on the
90° elbow, is test port No. 3. The air then passes through a
three lobed, positive displacement blower. After the blower
exhaust silencer, is test port No. 4. All flow then passes through
- A Complete Vacuum Service 'Jo Industry
42
-------
Mr. Roger Hancock
November 30, 1979
Page 2
the blower safety output filter. This.is a multiple section,
specially coated, absolute filter material, with estimated
efficiency of 99.99%.
Test ports No. 1 and No. 2 essentially see the same quality
of air. The two locations were provided in order to provide
different air flow patters for the sampling probes. Test ports
No. 3 and No. 4 also see the same quality of air. However, No. 3
is on the vacuum side of the blower and No. 4 is on the positive
side.
The storage section of the vacuum body is internally equip-
ped with multiple water misting devices. The truck chassis has
a 100 gallon water tank for storage of amended water.
All vacuum truck functions are operated by two main control
panels. The primary logic is handled by a 12 Volt, D.C.,
electronic control circuit. To insure maximum reliability and
safety, the circuit is fail-safe. Redundant back-up is utilized
for the secondary and safety sections. L.E.D.'s indicate the
status of operating conditions. The upper control panel inter-
faces electrical signals to air logic. All air signals originate
from this panel. Dual selectors allow the trurk operator to
monitor each individual section of air flow pattern within the
vacuum systems.
We are naturally, extremely interested in all test inform-
ation gathered from the project. We would appreciate copies of
any reports relative to the project.
During the test, we did not have the opportunity to evaluate
any mechanical devices for physically removing the asbestos from
the wall and ceiling surfaces. We hope that these devices will
further reduce fiber count within the work area. The fully
refined tools would be mounted within the vacuum wand. This
should provide consistently lower fiber counts. We will keep
you appraised as to tool developement.
If we may be of further service, please feel free to contact
us.
Very truly yours,
^^ty&^l^t^
Robert De Mane
RD/kw
cc: Dr. Robert Sawyer
Tucker Deming
file (2)
43
-------
ADVANCED
•:.tFVVK u .SYSTEMS INC.
661 - 671 FRELINGHUYSEN AVENUE
NEWARK. NEW JERSEY 07114
(2O1) 344 ?4OO
TRUCK MOUNTED VACUUM LOADER
MODEL AS-10
General Description
The Model, AS-10 is a truck mounted mobil vacuum loader,
The unit utilizes a heavy duty, reinforced vacuum
receiving chamber. The vacuum loader truck is capable
of vacuuming materials such as; dusts, sludges,
slurries, gravel, catalyst and oil spills. 'Various
materials can be air conveyed at distances up to 700'.
Body Assembly
Body construction consists of one, 10 cu. yd., heavy
duty reinforced vacuum chamber. Chamber is fabricated
from 3/16" steel plate, braced internally and externally
with structural channel.
Blower
One heavy duty positive displacement, roots type blower,
Consisting of two figure eight impellers, rotating in
opposite directions to move entrapped air around the
case to the port outlet.
AS-10
COMFL.CT HYDRAULIC AND ELECTRONIC SYSTEMS . MAINTENANCE ON ALL TYPES OF EQUIPMENT
44
-------
ADVANCED
SERVICE SYSTEMS INC.
661.671 FRELINGHUYSEN AVENUE
NEWARK. NEW JERSEY O7114
(2O1) 344-24OO
Filtration
Primary filtration centrifugal type separators. 50
micron and larger to 90% efficiency. Secondary
filtration, high'performance cyclbnes with spin out
and high velocity section. 15 micron and larger to
95% efficiency. Final filtration, dry element 99.50%
all particle size 3 micron and larger. Safety element
built in to final filtration section.
Special Filtration and Modification
Filtration
Three stage, heavy duty, dry type system. Primary
filtration stage, multiple element sections in parallel,
Nominal efficiancy, 99.50%. Secondary filtration, two
stage, heavy duty high efficiency in series, nominal
efficiency 99.95%. Third stage, positive pressure side
of blower, special modified and coated type element,
nominal efficiency, 99.99%.
Control Circuit Protection and Controls
Complete air control circuitry,, fail safe type with
redundant back-up. Each stage of filtration is diff-
erentially sensed and protected by electronic cells.
Automatic system shut down will occur at any time
pressure drop reaches 25% of maximum safe value. Equip-
ment shut-off is a two stage operation. Blower R.P.M.
is dropped to minimum operating speed. System vents and
blower speed are brought to idle, after a pre-set inter-
val, complete shut down occurs. L.E.D. fault indicating
lights identify reason for system shut-off.
AS-10
HVOHMU..C AND ELECT»ON,C ST.TCM. - M».HT«N»«CE ON ALL TYPM OF EOU,P«ENT
45
-------
ADVANCED
SERV.'Ci: SYSTEMS INC.
661 - 671 FRELINOHUYSEN AVENUE
NEWARK. NEW JERSEY O7114
(2O1) 344-24OO
Engine and Blower Protection
Diesel engine is protected by automatic low water shut-
off, low oil pressure, and over temperature, watch guard
system.
Blowers and body are protected against:
Maximum vacuum level
Blower exhaust temperature
Differential final filtration pressure
Full body level
Out phase fault shut-off
Blower P.T.O. interlock
Locked blower shut-down
Pre-filter warning
Instrumentation
Blower Vacuum 0-30" Hg.
Filter differential pressure
Oil pressure
Ampmeter
Water tank pressure
L.E.D. status lights
Instrumentation - Additional for Asbestos
0-30" Hg. Vacuum gage, glycerin filled and
pulsation dampened
2-12 Gal./min. water flow
0-100" W,C. differential gage with dual 12
position selectors
0-100 P.S.I. Primary air pressure
0-100 Secondary air pressure
0-75 Water tank pressure
100-250°F. Primary air temperature
150-350°F. Secondary air temperature
0-3600 R.P.M. Indicator
1500-3000 P.S.I. Hydraulic pressure gage.
Full body depth sensor, R.F. type
Liquid level - Mechanical type
AS-10
, ill HVDRAUUIC AND ELECTRONIC GYITIM* . MAINTENANCE ON ALL TYPES OF EQUIPMENT
46
-------
ADVANCED
SERVICE SYSTEMS INC.
681 . 671 FRELINGHUYSEN AVENUE
NEWARK, NEW JERSEY O7114
(2O1) 344-24OO
Hydraulic System
P.T.O. drive continuous duty 420 Vickers pump. Three
bank manual control valve with built in pressure
relief. Full return line filter, 10 micron rating.
Paint
Cab and chassis, Imron Silver.
Imron Blue.
Body and pipe racks,
H,«U«UC
E«CT.OH,C
AS-10
47
OH
-------
rfDwersthed
A/acuum
Ot
671 Frelinghuysen Avenue
Newaik, N. J. 07114
(201) 242 /OQ2
bb1 Host HoaJ
Cili.cill "11.11. (JOI.i' UP& '•''!
(Vd.i, 622-0493
j October 29, 1979
!
i Mr. Dennis F. Finn
j Environmental Engineer
; IIT Research Institute
; 10 West 35th Street
! Chicago, Illinois 60616
i
I Dear Dennis ,
i
Regarding our conversation for air sampling at the Bucks Harbor
facility. We have finalized on an optimum air flow for this job.
i Subject to any requirements by you to the contrary, the line velo-
cities would' be; 4" Dia. tube, 19,500 F.p.M., 6" Dia. tube, 8680
F.P.M., 8" Dia. tube, 4870 F.P.M. An interesting area for monitoring
will be checking the ongoing filter efficiency between the primary
air filters and secondary air filters. We suspect that efficiency
should improve as the filters "load".
Look forward to hearing from you soon.
Very truly yours,
Robert De Mane
RD/kw
A Ciiin/ilt'lt' Vacuum ;mrvi<,t. /,•» lii'tusiiy
48
-------
APPENDIX B
BULK SAMPLE AND WIPE SAMPLE ANALYSIS PROCEDURES:
POLARIZED LIGHT MICROSCOPY AND X-RAY DIFFRACTION
BULK SAMPLE POLARIZED LIGHT MICROSCOPY ANALYSIS METHODS
Clumps of the distinctly different phases, and bundles of obvious fibers
were plucked from each sample and mounted in standard immersion oil
(nD = 1.515). The samples were examined by polarized light microscopy to
determine other phases present and what additional sample preparation steps
would be required in order to complete the analysis.
The polarized light microscopical analysis revealed the presence of
obvious chrysotile asbestos, an amphibolic asbestos type, abundant plaster-
mortar material (calcium sulphates and carbonates), and minor quantities
of asbestos gangue minerals.
To simplify the asbestos quantification, the plaster material was dis-
solved away in dilute acetic acid. A weighed portion of each sample was
digested in warmed, dilute acid for 1 hour. Frequent stirring insured dis-
solution of all the pi aster material. The non-soluble portion of the suspen-
sion was recovered on a tared membrane filter and was thoroughly washed with
filtered, deionized water. The dried residue was then weighed, and the per-
cent weight lost, which represented the dissolved plaster-mortar material,
was calculated.
Concentrations of each asbestos type present in the distinctly different
colored phases were estimated microscopically.
The amosite (more accurately termed fibrous grunerite) identification
was made by mounting some of the amphibole fibers in np = 1.660 standard
refractive index liquid. The refractive indices of the amphibole fibers
were found to correspond most closely to those reported for grunerite.1
1 Hurlbut, C.S., Jr., and C. Klein. Manual of Mineralogy.. John Wiley & Sons,
New York, 1977. 532pp.
$
49
-------
ANALYSIS OF ASBESTOS IN INSULATION
CONTACT NAME
AGENCY
AGENCY ADDRESS
ID NUMBER
4-1
PHONE
BUILDING NAME
BUILDING ADDRESS
ROOM (HALL)
SAMPLED FROM
SAMPLED BY
FRIABILITY
SHIPPED ON
ON
RECEIVED
ANALYST JLG
PLM INSTRUMENT
ANALYSIS RESULTS
ANALYSIS DATE
12/1/79
SUPPLEMENTARY ANALYSES.
SAMPLE DESCRIPTION
Light-brownish overall; clump of light-grayish
material interspersed; fibers obvious—more fibrous than the 16-1 and 16-2
samples.
ASBESTOS TYPE Chrysotile and amosite (anthophyllite contaminants in amosite)
Total ^621 asbestos: brownish material— ^85% amosite,
15% chrysotilc; grayish material-—65% chrysotilo.35%amosite
OTHER FIBROUS COMPONENTS MASS FIBER DIAMETERS, ]m
PER CENT RANGE MEAN
ASBESTOS CONCENTRATION
fiber glass
rock, slag wool
cellulose
other
NONFIBROUS COMPONENTS
pi aster.mortar <36%
iron oxides
hornblende
REPORT BY
«1
«1
«1
prismatic amphiboles
non-fibrous serpentine
clavs
REPORT DATE
50
-------
ANALYSIS OF ASBESTOS IN INSULATION
ID NUMBER
16-1
CONTACT NAME
AGENCY .
AGENCY ADDRESS
PHONE
BUILDING NAME
BUILDING ADDRESS
ROOM (HALL)
SAMPLED FROM
SAMPLED BY
FRIABILITY
SHIPPED ON
ON
RECEIVED
ANALYST
JLG
ANALYSIS RESULTS
ANALYSIS DATE
12/1/79
PLM INSTRUMENT
SUPPLEMENTARY ANALYSES --
SAMPLE DESCRIPTION
Light-grayish overall, with clumps of light brown
jnaterial; fibers very obvious.
ASBESTOS TYPE Chrysotile and amosite (anthophvTh'te contaminants in amosite)
..RF<:Tn_ pmurcMTDflTTriM Total ^65%: grayish material—75% chrysotile, 25% amosite;
AbBESTOS CONCENTRATION __ brownish material-00% atnosite. 20% chrysotile.
OTHER FIBROUS COMPONENTS MASS ' ,. FIBER DIAMETERS, ym
PER CENT RANGE MEAN
fiber glass
rock, slag wool
cellulose
other
NONFIBROUS COMPONENTS
plaster, mortar
iron oxides
hornblende
REPORT BY
33%
«1
«1
«1
prismatic amphiboles
non-fibrous serpentine
clavs ,_
REPORT DATE
51
-------
ANALYSIS OF ASBESTOS IN INSULATION
CONTACT NAME
AGENCY
AGENCY ADDRESS
BUILDING NAME
BUILDING ADDRESS
ROOM (HALL)
SAMPLED FROM
SAMPLED BY
FRIABILITY
SHIPPED ON
ID NUMBER
16-2
PHONE
ON
RECEIVED
ANALYST
JLG
PLM INSTRUMENT
ANALYSIS RESULTS
ANALYSIS DATE
12/1/79
SUPPLEMENTARY ANALYSES --
SAMPLE DESCRIPTION Light-grayish overall; clumps of light-brownish and
whiter material evident; fibers obvious.
ASBESTOS TYPE
Chrvsotile and amosite
ASBESTOS CONCENTRATION
OTHER FIBROUS COMPONENTS
fiber glass
rock, slag wool
cellulose
other
NONFIBROUS COMPONENTS
pi aster,mortar <33%_
iron oxides
hornblende
REPORT BY
Total ^65% asbestos: brownish material—85% amosite,
15% chrysotile, grayish nidlet tal —00% Uirysotile. 20% amosite
MASS
PER CENT
FIBER DIAMETERS, ym
RANGE MEAN
prismatic amphibole
non-fibrous serpentine
cl ays
REPORT DATE
52
-------
BULK SAMPLES FROM GARAGE CEILING
Bundles of chrysotile fibers coated with plaster
mortar; slightly uncrossed polars; 82X.
Bundles of the harsher amosite (grunerite) asbestos
fibers coated with plaster-mortar; slightly uncrossed
polars; 82X,
-------
POLARIZED LIGHT MICROSCOPIC ANALYSIS OF WIPE AND VACUUM SWEEP SAMPLES
Seven aerosol filter sampling cassettes and one towel wiping sample were
submitted for polarized light microscopic analysis. The samples represented
sweepings of dust from various floor and structural surfaces.
Since the membrane filters in the aerosol sampling cassettes were so
loaded with large particles that a loose, removable dust was visible, the
loose dust rather than the membranes were mounted for microscopic analysis.
In all samples, clumps of fibers were present as "lint balls," in addition
to a loose, free-flowing fine dust. Tweezers were used to remove samples
of the "lint balls," while a spatula was used to remove samples of the loose
dust for mounting. Materials were mounted on glass slides in standard immer-
sion oil (nD = 1.515) for microscopic analysis. The sample for microsopic
analysis was removed from the towel wiping by scraping the visible dust
deposit with a scalpel; the removed dust was mounted in the same manner as
the other samples.
The prepared samples were examined with a polarized light microscope
at magnifications ranging from 62X through 400X. Particle types observed
were identified from optical and physical properties. Concentrations were
estimated from the relative number abundance of each particle type after
size and density corrections were made.
The attached tables list the components noted in each sample and their
relative abundance. Photomicrographs of each sample are also included. Arrows
indicate the asbestos fibers (amphibole, in most cases).
In most samples, the amphibole asbestos fibers were more abundant than
the chrysotile asbestos fibers, even though chrysotile was in the outermost
layer of insulation. Several factors probably resulted in the release of
more amphibole than chrysotile asbestos. Most of the chrysotile detected
inthe samples was heavily coated with, and actually encapsulated by, paint.
The paint probably served as an effective coating which minimized release
of the chrysotile. It should be mentioned that in several samples the chryso-
tile concentration could be higher than that listed; the paint coatings hin-
dered and probably prevented detection of all chrysotile fiber bundles. The
amphibole asbestos is much more friable, in terms of both fiber length and
bundle width, than chrysotile asbestos. Therefore, more small fibers and
fiber bundles of amphibole would be released, with less disturbing force,
than chrysotile fibers.
54
-------
TABLE B-l. GARAGE FLOOR NEAR AIR-CONDITIONING PUMPS
Primary Components
quartz
textile, paper fibers
Major Components
micas
paint spheres, flakes
iron oxides
Minor Components
amphibole asbestos (<1-1220 ym, mean ^20 ym)
metal fragments
clay, humus
carbonates
wood fibers
cement
partial combustion fragments
aluminum oxides
Trace Components
chrysotile asbestos (M-360 ym)
fiberglass
rubber tire fragments
vehicle exhaust
plant parts
insect parts
starch
rodent hairs
human hairs
skin flakes
grinding abrasives
diatoms
Chrysotile concentration could possibly approach \%>
some chrysotile was noted encapsulated in paint.
55
-------
GARAGE FLOOR NEAR AIR-CONDITIONING PUMPS
Lint ball; 82X.
* '
Fine dust; 208X.
-------
TABLE B-2. GARAGE INTERIOR WALL WIPE SAMPLE
(150 cm from floor)
Primary Components
plaster, mortar
quartz
Major Components
wood fibers
paint spheres, flakes
metal fragments
iron oxides
aluminum oxides
Minor Components
paper fibers
textile fibers
micas
hornblende, iron silicates
carbonates
partial combustion fragments
cement
clays, humus
Trace Components
amphibole asbestos (<1-440 ym, mean ^24 ym)
chrysotile asbestos (<1-500 urn)
fiberglass (organic bound)
grinding abrasives
pollens, spores
plant parts
insect parts
human hair
rodent hair
rubber tire fragments
glassy flyash
57
-------
GARAGE INTERIOR WALL WIPE SAMPLE
(150 cm above floor)
V
fcf
te
*
: •; f
4Wp»
Fine dust; 208X.
-------
TABLE B-3. VERTICAL SURFACE OF WIDE FLANGE OF I-BEAM
(150 cm above garage floor)
Primary Components
paper, wood fibers
Major Components
amphibole asbestos (<1-1700 urn, mean ^35 ym)
plaster
paint flakes, spheres
textile fibers
quartz
micas
Minor Components
chrysotile asbestos ( 1-600 pm) other minerals
iron oxides
metal oxides
partial combustion fragments
clays, humus
asphaltic material
Trace Components
fiberglass (organic bound)
rubber tire fragments
vehicle exhaust
insect parts
pollens, spores
plant tissue
skin flakes
human hair
plant parts
Chrysotile was not encapsulated in paint in this sample.
59
-------
VERTICAL SURFACE OF WIDE FLANGE I-BEAM
(150 cm above garage floor)
Lint ball; 82X; straight dark fibers are amphibole
asbestos bundles.
Fine dust; 208X; fibrous particles are amphibole
asbestos.
-------
TABLE B-4. GARAGE FLOOR NEAR BOILER ROOM
•^"^^ ^^^^
Primary Components
quartz
paint flakes, spheres
Major Components
carbonates
plaster, mortar
partial combustion fragments
wood fibers
iron oxides
hornblende and other iron-'silicates
Minor Components
mica metal flakes
paper fibers
textile fibers
, clays, humus
Trace Components
amphibole asbestos (<1-820 ym, mean <30 ym)
chrysotile asbestos (<1-1000 ym, mean ^18 ym)
fiberglass (organic bound)
grinding abrasives (corundum, silicon carbide)
plant parts
insect parts
pollens, spores
rubber tire fragments
vehicle exhaust
human hair
diatoms
Chrysotile was not detected as an encapsulated phase
in this sample. Number concentrations of amphibole
fibers were only slightly greater than chrysotile
fiber concentrations.
61
-------
GARAGE FLOOR NEAR BOILER ROOM
Fine dust; 208X.
62
-------
TABLE B-5. TOP HORIZONTAL SURFACE OF
GARAGE LEVEL AIR-CONDITIONERS
Primary Components
quartz
Major Components^
paper fibers
textile fibers
partial combustion fragments
paint flakes
paint spheres
plaster, mortar
horneblende and other iron-silicates
Minor Components
amphibole asbestos (<1-1000 ym, mean ^20 urn)
mica
iron oxides
carbonates
clays, humus
vermiculite
other minerals
metal flakes
wood fibers
Trace Components
chrysotile asbestos (<1-680 ym)
fiberglass (organic resin coating)
insect parts
plant parts
pollens, spores
rodent hairs
skin flakes
rubber tire fragments
vehicle exhaust
human hair
Conceivably there could be up to 1% chrysotile.
Chrysotile was detected encapsulated in some of the
paint flakes.
63
-------
TOP SURFACE OF GARAGE LEVEL AIR-CONDITIONERS
• I*
\
f
-------
TABLE B-6. WIPE SAMPLE OF RECEIVING RESERVOIR DOOR
AFTER DUMP AND DECONTAMINATION
Primary Components (>25% by mass)
quartz
Major Components (5-25% by mass)
hornblende and other iron silicates
micas
iron oxides
Minor Components (0.5-5% by mass)
rubber tire fragments
paper fibers
textile fibers
metal fragments
carbonates
asphalt
paint fragments
clays, humus
plaster, mortar
partial combustion fragments
Trace Components (<0.5% by mass)
chrysotile asbestos
amphibole asbestos
fiberglass
vehicle exhaust
grinding abrasives
plant parts
insect parts
wood fibers
flyash spheres
65
-------
WIPE SAMPLE OF RESERVOIR DOOR AFTER
DUMP AND DECONTAMINATION
* •
4
"
A
•
» *
-,?•
* *
,
*
-------
GENERAL DESCRIPTION OF X-RAY DIFFRACTION TECHNIQUE AND
INSTRUMENT SPECIFICATIONS
The basic process utilized in x-ray diffraction is the interaction or
interference of any crystalline structure on a focused beam of x-rays The
interference results in a splitting of the incident beam Into multiple parts
with varying intensity. The direction and intensity of the individual com-
ponents provide a unique signtture or spectrum which can be used to identify
the crystal. Generally, only one or a few compounds can be simultaneously
analyzed since the patterns can be individually complex. If more than one
species of a crystal is present, a super-imposition of complex spectra can
occur which complicates the analysis.
The features which make x-ray diffraction analysis useful include the
following:
• The technique is one of the very few which provide
structure, i.e., molecular information, rather than
merely elemental content.
• The technique is broadly applicable—the unique
diffraction signatures for over 25,000 organic and
inorganic compounds have been catalogued for use in
manual or computerized search files.
• The technique is non-destructive—samples which must
be preserved or examined by other techniques are not
destroyed.
• Sample preparation is minimal—typically, a thin
layer sample may be examined directly.
The general level of the detectability for chrysotile (serpentine asbes-
tos), a mineral of interest found in dust for which x-ray diffraction is an
attractive analytical technique, is about 10 yg-
The probable analysis procedure for chrysotile and other major minerals
would involve the following steps:
1) Collect the sample. Mount each clearly different
material in a suitable holder.
2) Make a preliminary 29 scan of the raw, as-collected
material over a wide angular range (5° to 75 ) to
obtain qualitative estimates of composition, analytical
interferences, and interference-free regions for use
as an internal standard.
3) Add an internal standard, if necessary (e.g., CaF2 is
commonly used if there are no interferences), and
mix (using ultrasonic agitation) with the sample
using a wetting agent. Dry.
4) Remount specimen with internal reference standard.
67
-------
5) Measure peak areas of interest (e.g., at 4.26 A for
a-quartz, 405 A cristobalite, and 3.15 A for calcium
fluoride).
6) Convert to absolute mass units using the internal
standard.
MAJOR SPECIFICATIONS FOR THE RIGAKU 12 KW HIGH BRILLIANCE ROTATING
ANODE DIFFRACTOMETER AND ASSOCIATED EQUIPMENT
H a rdwa re Specif i c a t i ons
Generator Power . ,
Source Dimensions
Sample Holders,
Goniometer.
Goniometer Scanning Speed .
Goniometer step size (26) .
Goniometer Range (26) . . .
Monochromator
Data Computer System.
Major Software Specifications
Diffractometer Software ,
12 kilowatt x-ray tube with rotating
copper anode.
Source dimensions of 0.5 x 10 mm on the
anode gives 0.05 mm x 10 mm line source;
can be modified to give 0.1 x 1 mm on the
anode for,0.1 x 0.1 mm effective spot.
Automatic 43 sample changer accepting
power, plate, or paper filter samples.
(Filter holder also interchanges into
x-ray fluorescence spectrometer.)
Vertical wide-angle goniometer (185 mm
radius) with complete computer control
of data acquisition in either step or
continuous mode.
11 programmable scanning speeds of 32, 16,
8, 4, 2, 1, 1/2, 1/4, 1/8, 1/6, l/32°/min.
8 programmable step sizes (28) or (0.001°,
0.002°, 0.1°) x (1, 2, 5).
Programmable step sizes (26) is -5° to
+130° (26).
A curved graphite monochromator with 22.4
cm radius is available to isolate the
copper K alpha and enhance the signal to
noise ratio.
Digital Equipment Corporation 11/03 com-
puter with 32 k memory, LA-36 terminal/
printer, RX02 dual floppy mass storage,
and LA-180 line printer. The operating
system is RT-11 CLASS (RT-11 Fortran in
preparation).
• Step Scan. Step scan through specified
angular range with linear background
correction based on endpoint values.
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Printout gives 2e, gross counts, net-
counts, and background.
Continuous Scan. Continuous scan through
specified angular range. Printout gives
26 and gives counts in successive time
intervals.
Search. Continuous scan through specified
angular range followed by peak detection
and tabulation of 25 most intense peaks.
Normalizes, sorts, and prints d-spacing
for most intense lines.
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APPENDIX C
PERSONAL, AREA, AND HIGH-VOLUME SAMPLE ANALYSIS PROCEDURES
MILLIPORE: RECOMMENDED PRACTICE
Procedure for rendering MF-Millipore (mixed esters of cellulose) and
Celotate (cellulose acetate) membrane filters transparent.
This procedure provides a chemical clearing technique that yields a
transparent membrane permanently affixed to a glass slide and because of
the nature of the clearing procedure, the contamination is also permanently
affixed to the membrane resulting in a permanent sample.
Outline of Method
Contaminants must be collected on a MF-Millipore (white or black plain)
or Celotate membrane disc where vacuum has been used to impinge the par-
ticles upon the surface of the filter. The filter disc is rendered trans-
parent by dissolution, thus, the particles can be observed using transmitted
light microscopy.
Apparatus
• Glass slides 5.1 cm x 7.6 cm (for 37 and 47 mm filters)
Millipore Catalog # XX10 076 15
• Filter forceps, stainless, smooth-tip
Millipore Catalog # XX62 000 06
• Eyedroppers with rubber bulbs
• Watchglass (diameter greater than 47 mm)
• Glass syringe (50-100 ml)
• Micro-syringe, Luer inlet, 25 mm
Mi Hi pore Catalog # XX30 025 00
• Fluoropore membrane filters (pore size 0.2 ym)
Mi Hi pore Catalog # FGLP 025 00
• Large diameter petri dishes
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Reagents
• Clearing Solution A: 33 ml Hexane, Technical Grade
33 ml 1,2-Dichloroethane, Technical Grade
33 ml 1,4-Dioxane, Technical Grade
• Clearing Solution B: Acetone, Technical Grade
Filter Clearing Procedure
1) Filter Clearing Solution A using FGLP (0.2 pm pore size) filter into
pre-cleaned container.
2) Using an eyedropper, freshly rinsed with a filter, solvent (Freon&TF
is recommended), dispense sufficient Clearing Solution A to thorough-
ly wet a cleaned 5.1 cm x 7.6 cm microscope slid,e.
3) Carefully roll the dry test filter particle side up, onto the pre-
wetted glass slide. (Caution: Do not release membrane on this
slide.) Immediately roll the wet filter onto a clean, dry glass
slide and cover the glass petri dish.
4) After 30 seconds, remove the glass petri dish and invert the sample
over a watch glass half filled with acetone. Allow the sample to
become completely transparent (2 to 5 minutes exposure time to the
aceton,e vapors).
5) Remove the sample from the watch glass and place on a level surface,
covering it with the petri dish.
6) Allow the filter to dry 2 to 5 minutes at room temperature. Filter
is now ready for analysis.
ASBESTOS ANALYSIS BY ELECTRON MICROSCOPY (EM)
Selected filter samples of the work area, upwind ambient air, and down-
wind ambient air were analyzed by electron microscopy to assess and/or verify
the asbestos concentration. A JEOL 100C transmission, scanning electron
microscope (EM) with chemical elemental analytical capability (energy dis-
persive x-ray spectrometer) was used for the fiber counting and identifi-
cation. This analytical EM provides electron diffraction analysis and x-ray
elemental analysis in addition to the observation and photographing of micro-
images.
The coded filter samples were examined for asbestos concentration in
accordance with the EPA's provisional methodology (ref. Samudra, et al.,
EPA 600/2-77-178 revised June 1978) and outlined below.
Sample Preparation
A portion of the sample collected on Nuclepore filter was cut and
mounted on a clean glass slide. The mounted membrane section was coated
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with a carbon film (^0.40 nm in thickness) in a JEOL JEE-4C vacuum evaporator.
Samples collected on Millipore filters did not require a carbon film coating.
A modified Jaffe Wick Washer was used to dissolve the filter membrane.
In a Class 100 clean bench, a small section of filter membrane (<3 mm diam-
eter) was placed on a 200 mesh carbon-coated copper electron microscope grid.
The EM grid and filter membrane pane was placed on a 200 mesh stainless steel
screen which was on a stack of filter paper in a glass petri dish. Enough
solvent was added to the petri dish to soak the filter paper stack and thus
enable the wicking action to gently dissolve the filter membrane and leave
the particles on the carbon-coated substrate of the EM grid.
Chloroform was used for dissolving the Nuclepore membrane and acetone
was used for Mi Hi pore filters. The petri dish was kept covered for approxi-
mately 24-48 hours, except for periodic addition of solvent. After the speci-
fied wetting period, the stainless steel mesh plus grid was placed on a clean
filter paper to allow the solvent to evaporate. The grid was then placed
in a covered grid box for EM analysis.
Analytical Method
The prepared grid was examined at low magnification (250X and 1000X)
for film integrity, extraneous particle concentration, and uniformity of
deposition. A grid opening was selected at random for critical examination
at an instrument magnification of 20,OOOX. The grid opening was scanned
by a back and forth traverse and each fiber (defined as a particulate with
a minimum of 3:1 length to width aspect ratio and with relatively parallel
sides) was counted, the width and length measured, and a selected area elec-
tron diffraction (SAED) pattern observed, if possible. Since observation
of morphology, measurements, and SAED identification were conducted at 0°
tilt angle, additional SAED analyses were conducted at a 40° tilt angle for
selected fibers. A 40° tilt angle facilitated x-ray analysis of the fiber
by the energy dispersive spectrometer for elemental identification. Photo-
graphs were taken of selected fibers and their SAED pattern at 0° and 40°
tilt angles. Their corresponding x-ray spectra were also photographed.
Approximately 100 fibers were to be counted or a minimum of ten (10)
grid openings (approximately 3000 fields) were to be examined.
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APPENDIX D
FIBROUS AEROSOL MONITOR DESCRIPTION AND OPERATION
PRINCIPLE OF OPERATION
Aerosol particles are sampled at 2.0 1pm through an inverted U-duct
which prevents the direct access of large dust particles into the flow-
direction tube. The aerosol then enters a horizontal tube in which a laminar
profile is attained.
t
Fibers are induced to rotate rapidly by application of a rotating high-
intensity electric field. Fibers rotating along the centerline of the tube
are simultaneously illuminated by a continuous HeNe laser. A photomultiplier
tube detects light scattered perpendicular to the axis of illumination.
Maximum intensity of light scattered from fibers occurs in the plane perpen-
dicular to the fiber axis, which contains the axis of illumination. The
frequency of light scattering pulses produced by the fibers and detected
by the PMT is'thus determined by the frequency of the rotating field. Syn-
chronous detection then permits enhanced discrimination of light pulses from
fibers versus light pulses from nonfibrous aerosols. Fiber length discrimin-
ation is achieved by pulse shape and amplitude discrimination.
Particle pulses which meet the selection criteria necessary to identify
them as fibers greater than 5 pro long are counted. At the end of the operator
preselected sampling period, fiber counts are automatically converted into
fiber concentration and displayed.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-600/2-80-088
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Evaluation of a Commercial Vacuum System for the
Removal of Asbestos
5. REPORT DATE
May 1980
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
R.W.Welker,D. F. Finn,J.D.Stockham, and
R.P.Hancock
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
IIT Research Institute
10 West 35th Street
Chicago, Illinois 60616
10. PROGRAM ELEMENT NO.
C1Y-L1B
11. CONTRACT/GRANT NO.
68-02-2617, Task 10
12. SPONSORING AGENCY NAME AND ADDRESS
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
Task Final; 10-12/79
14. SPONSORING AGENCY CODE
EPA/600/13
15.SUPPLEMENTARY NOTES jERL-RTP project officer is David C. Sanchez, Mail Drop 62,
919/541-2547.
is. ABSTRACT The repOrt gjves results of a. brief field study that included measurement
of personal, area, and environmental asbestos exposures resulting from wet and
dry asbestos removal using a commercial vacuum System. Personal and area (in-
door) asbestos concentrations during dry removal were less than 1 fiber/cu cm, as
measured by NIOSH P and CAM 239 when the vacuum system was used. Asbestos
released to the environment from the vacuum system's three-stage exhaust filter
was negligible. Asbestos was released from the operator's protective garments
when he exited the work area to service the vacuum system. Sources of asbestos
fiber release associated with vacuum system operation were identified; these occur-
red during operation, disassembly, and asbestos disposal. Following vacuum shut-
down, liquid drained from the collection reservoir due to inadequate door seals.
During vacuum hose disassembly, bulk losses of asbestos-containing materials
occurred. During disposal, the exterior of the vacuum truck became contaminated
as the reservoir was emptied. Additional dry removal testing is required.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COS AT I Field/Group
Pollution
Asbestos
Vacuum Cleaners
Vacuum Filters
Vacuum Filtration
Pollution Control
Stationary Sources
13B
HE
13G
13K
07A
3. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (ThisReport)
Unclassified
21. NO. OF PAGES
79
20. SECURITY CLASS (Thispage)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
74
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