Report on the Asbestos Incident in T-747 and T-739
Magnuson Health Sciences Building
University of Washington
July 6 to August 9, 2005
Report on the Asbestos Incident in T-747 and T-739 of
Magnuson Health Sciences Building
University of Washington
July 6 to August 9, 2005
Executive Summary
During the period of July 6, 2005 through August 9, 2005, construction related debris entered
rooms T-747 and T-739 of the Magnuson Health Sciences Building. Because a classroom
renovation project, which included asbestos abatement, was underway in room T-639, directly
below rooms T-747 and T-739, the debris was assumed to potentially contain some level of
asbestos contamination. The rooms on the seventh floor were not considered part of the project
area located on the floor below and they were therefore not part of the project containment area.
Rooms T-747 and T-739 were occupied on most days during this period by classes, seminars,
and other events. There can be no definitive assessment of exposure levels since sampling for
asbestos contamination did not occur until sometime after the actual incident, due to a delay in
the discovery of the impact to areas outside the primary construction area. The results reported
in this document thus depend on secondary data sources. It can be assumed that individuals
who entered the rooms while potential contamination was present may have received an
asbestos exposure above asbestos levels that are background levels in those rooms.
The information obtained from room occupants demonstrates that on three occasions during
one course and on one occasion during another course, dust was observed entering room T747 while classes were in session. Although actual exposure levels were not possible to
ascertain, indications are that individuals attending these classes were likely to have had
exposures that exceeded the regulatory short term exposure limit for a fifteen-minute exposure
and the eight-hour time weighted permissible exposure limit when averaged for a day
(Washington Administrative Code 296-62-077). Custodians who operated vacuums in the room
for short periods may also have exceeded the permissible exposure limits. Indications are that
individuals who entered the room at times other the than four times described above may have
been exposed to low levels of asbestos if asbestos-contaminated debris was disturbed.
Further evaluation of the possible exposures for these occupants indicates that, even if worst
case exposure levels are assumed, the assumed exposures do not present an identifiable risk
higher than normal levels, due to the relatively short period of time that personnel were
exposed. Thus it would be considered unnecessary for Individuals who were assumed to have
been exposed to seek any medical follow-up. Various procedures to minimize the possibility of a
situation like this happening again are in the process of being implemented, as described in the
body of the report.
If more information about the incident is desired, Denis Sapiro, Manager of the Occupational
Health and Safety Office in Environmental Health and Safety can be contacted at 206-221-4247
or by email at [email protected].
i
Table of Contents
Executive Summary ……………………………………………………………………..
i
Table of Contents………………………………………………………………….......... ii
Incident Background…………………………………………………………………….
1
Hazards of Asbestos…………………………………………………………………….
6
Questionnaire Responses………………………………………………………………
7
Discussion of Potential Exposures…………………………………………………….
8
Evaluation of Possible Exposure Risks………………………………………………. 12
Medical Follow-up Concerns………………………………………………………….. 16
Actions to Prevent Recurrence / Additional Follow-up Actions……………………. 17
Summary……………………………………………………………………………….
18
References……………………………………………………………………………… 19
Appendices……………………………………………………………………………..
20-33
Tables and Figures
Table 1.
Sodium Bicarbonate Blasting Episodes………………………………
2
Table 2.
Results of Bulk Samples Collected August 5, 2005…………………
3
Table 3.
TEM Analyses of Air Samples while Cleaning, August 5, 2005……
8
Table 4.
TEM Analyses of Air Samples Collected during
Aggressive Treatment of Carpet, August 11, 2005………………....
9
Table 5.
Approximate Durations of Different Classes & Events in Rooms…
12
Table 6.
Exposure Estimates for Different Groups …………………………… 13
ii
Incident Background
Classroom Renovation Project in Room T-639
A project to renovate Lecture Hall T-639 of the Magnuson Health Sciences Building was
approved by the University of Washington Project Review Board and the Notice to
Proceed was issued on May 23, 2005, with the project design and administrative work
performed under the direction of the UW Capital Projects Office (CPO). As part of this
project, a decision was made to abate (remove) all the asbestos fireproofing sprayed on
to the ceiling pan and steel structure of the ceiling of Room T-639. This fireproofing
contained approximately 25% chrysotile asbestos.
The contractor who was awarded the bid to do this work was required to perform the
work in accordance with the University’s model specifications concerning asbestos
abatement and in compliance with applicable WISHA, OSHA, PSCAA, Ecology, and
EPA regulations by an accredited abatement company with oversight of their work
performed by an asbestos consultant selected by the University. Required procedures
included installation of containment curtains and sealing ventilation ducts and other
openings, construction of “decon” rooms including showers to be used by personnel
working in the area, operation of High Efficiency Particulate Air (HEPA) filter systems to
keep the abatement area under negative pressure, and monitoring by the asbestos
consultant of perimeter areas outside the containment. In addition, water was sprayed
on the fireproofing to moisten it and help reduce the amounts of asbestos fibers floating
inside the work area, using a compressor–powered airless water sprayer.
Much of the work involved manual scrapping with various hand tools, but beginning
July 6, 2005, the contractor implemented a new process that used an abrasive blaster
containing sodium bicarbonate as the blasting media. This device blows out sodium
bicarbonate at high pressure to create a high velocity stream to dislodge the
fireproofing. When the abrasive blasting media contacts the fireproofing, it will abrade
some of the fireproofing. Asbestos contamination within the stream of sodium
bicarbonate will therefore vary from something less than the original asbestos level in
the fireproofing (25% chrysotile) to a non-detectable level depending on the relative
amounts of fireproofing and sodium bicarbonate abrasive.
Abrasive blasting in Room T-639 occurred on the dates shown in Table 1 Sodium
Bicarbonate Abrasive Blasting Episodes, per the asbestos consultant’s field notes.
From these notes, it can be observed that abrasive blasting was halted on four
occasions due to noise complaints (twice on one day). After the recurring work
stoppages, the abrasive blasting was done later in the day and in the evenings when
the rooms above T-639 were vacant. Abrasive blasting using sodium bicarbonate as
the media was halted on July 26, 2005 when it was determined by the contractor that
the bicarbonate abrasive blasting system was not being effective at removing the
remaining film of sprayed on fireproofing.
1
Table 1. Sodium Bicarbonate Abrasive Blasting Episodes
Day
Date
Shift
Wednesday
Thursday
Friday
Saturday
Tuesday
Wednesday
Thursday
July 6, 2005
July 7, 2005
July 8, 2005
July 9, 2005
July 12, 2005
July 13, 2005
July 14, 2005
Day
Day
Day
Day
Day
Day
Day
Friday
Saturday
Sunday
Tuesday
Wednesday
Thursday
Friday
Monday
Tuesday
July 15, 2005
July 16, 2005
July 17, 2005
July 19, 2005
July 20, 2005
July 21, 2005
July 22, 2005
July 25, 2005
July 26, 2005
Day
Day
Day
Day
Night
Night
Night
Night
Night
Comments from the Field Notes
Blasting stopped at 9:30 due to noise complaint by
instructor from the 7th floor, re-started at 14:10, stopped
at 14:30 due to noise complaint
Blasting stopped at 9:00 due to noise complaint
Blasting stopped at 9:30 due to noise complaint
Abrasive blasting with sodium carbonate terminated
Discovery of Debris in Rooms T-747 and T-739
Following a complaint the evening of August 4, 2005, that the projectors in the Media/
Projector Room T-747D were too dusty to project properly, personnel from the Health
Sciences Academic Services and Facilities (HSAS & F) inspected the room the morning
of August 5. They found a powder spread extensively in the Media Room and on top of
the projection equipment, and thinking it may have come from a construction project,
contacted UW Facilities Services Maintenance and Alterations staff.
A representative from that organization inspected the room the morning of August 5 and
determined that it appeared to be construction debris due to the project on the 6 floor
and that it could possibly be contaminated with asbestos. He advised UW HSAS & F to
close the room until the debris could be analyzed and contacted the UW Facilities
Services Maintenance and Alterations Asbestos Coordinator and the UW Construction
Coordinator for the T-639 project for evaluation of the debris.
Shortly before noon on August 5, the Asbestos Coordinator inspected the area along
with the UW Construction Coordinator and a representative from Environmental Health
and Safety (EH&S). They noted patterns of dust which had appeared to come from
holes between Rooms T-639 and T-747 with the most extensive dust accumulations
apparently in the Media/Projection Room (T-747D). Samples of the dust were collected
and levels were found to range from none detected (less than 1% asbestos) to 6%
chrysotile asbestos, as shown in Table 2, Results of Bulk Samples Collected August 5,
2005.
2
Table 2. Results of Bulk Samples Collected August 5, 2005
Sample
Number
Sample Location
13569-001
T-747 closet in northwest corner of
Lecture Room on floor and
furniture
13569-002
T-747 closet in northwest corner of
Lecture Room on floor and
furniture
13569-003
T-747 from metal communication
box in floor, 6’ south of north wall,
at center area
13569-004
T-747 from outside of metal tubing,
2nd row of seats, south wall of
room, front 7th seat from west wall,
microvac sample collected on filter
T-747 from center of south wall
under media/projection room
window, on cove base and carpet,
microvac sample collected on filter
Media/Projection Room T-747D,
directly under metal stand in center
of room on carpet, microvac
sample collected on filter
Media/Projection Room T-747D,
swipe of glass on side and top of
case locations in southwest corner
of room
Media/Projection Room T-747D,
from glass on side and top of case
location in southwest corner of
room, tapelift sample
T-747 from north wall area, 2’
south and 6’ east of northwest
corner of room, from carpet,
microvac sample on filter
T-747 from outside of metal tubing,
2nd row of seats, south wall of
room, front 7th seat from west wall,
microvac sample on filter
T-747 from outside of metal tubing,
2nd row of seats, south wall of
room, front 7th seat from west wall,
tapelift sample
T-739, from closet in northwest
corner of room, on carpet and
countertop
13569-005
13569-006
13569-007
13569-008
13569-009
13569-010
13569-011
13569-012
Material
Sampled
Off-white
fibrous
powdery
material
Off-white
fibrous
powdery
material
Off-white
fibrous
powdery
material
Off-white
fibrous
powdery
material
Off-white
fibrous
powdery
material
Off-white
fibrous
powdery
material
Off-white
fibrous
powdery
material
Off-white
dust on tape
Results
2% chrysotile
2% chrysotile
Duplicate sample of
first sample
No asbestos
detected
No asbestos
detected
No asbestos
detected
6% chrysotile
Chrysotile
Present
Small sample size
No asbestos
detected
Gray dust on
filter
No asbestos
detected
Gray dust on
filter
Less than 1%
chrysotile
Gray and
white dust on
tape
No asbestos
detected
Light gray
loose powder
2% chrysotile
3
Comments
Did not appear similar
to dust in Room T-747
The Asbestos Coordinator and EH&S
representative noted that dust had made a
pattern blowing away from various penetrations
through the T-747 floor, i.e., the electrical
conduit penetrations and seat mounting
brackets. They also inspected the classroom
next door, Room T-739. It was noted that the
storage closet off T-739 contained dust which
appeared older and not related to the
construction project. In addition the EH&S
representative and the Asbestos Coordinator
noted dust suspect from the asbestos project
along the common wall between T-747 and T739. The most visible accumulation of dust was
in T-747’s Media/Projection Room (T-747D).
Based on these observations, rooms T-739
and T-747 were presumed to be contaminated
with dust from the construction project with
asbestos contamination ranging from below
detectable levels up to 6%, and the areas were
closed until cleaning could be done.
Response
The cleaning of T-747 and T-739 was initiated
in the afternoon of Friday, August 5, 2005. The
rooms were cleared for routine occupancy
using the standard UW protocol, involving
visual inspection for any visible debris in the
rooms and Phase Contrast Microscopy (PCM)
testing of air samples to assure an airborne
asbestos level less than background levels or
0.01 fiber per cubic centimeter (f/cc)
(whichever was lower).
The rooms were cleared for re-occupancy and
normal classes resumed on Monday, August 8.
However, the rooms were re-closed at noon on
Tuesday, August 9 for additional testing after
EH&S raised the possibility that the carpeting
could retain fibers that could be released over
time with heavy use and wear. On Thursday,
August 11, 2005, “aggressive” sampling was
4
Asbestos Analysis Methods
Bulk Samples –
Materials are inspected visually
using an optical microscope using
the Polarized Light Microscopy
(PLM) technique, looking for
crystals with particular refraction
angles. The least amount of
asbestos which can be reliably
detected is typically 0.3 to 1% of
the total bulk quantity. A “tapelift”
sample can be used when there is
a very small amount of debris on a
flat surface, but the analysis can
only identify whether there is some
asbestos “present” and can’t
quantify the exact amount.
Air Samples –
A filter used to filter an air sample
is inspected visually under an
optical microscope using the
Phase Contrast Microscopy (PCM)
technique, looking for any type
fiber which is at least 5 microns
long and at least 3 times as long
as its diameter. The smallest fiber
visible has a diameter of about 0.5
microns. Knowing the amount of
air that flowed through the filter,
analysis results are shown as
fibers per cubic centimeter of air
(f/cc). PCM method results were
used to determine exposure limits
and risk assessments
Alternatively, the filter can be
analyzed using a Transmission
Electron Microscopy (TEM)
technique. Results are frequently
shown as “asbestos structures per
square millimeter of filter” which is
specific for asbestos but includes
clumps of fibers, too. This
technique detects smaller
asbestos fibers than can be seen
by PCM. TEM results can be
approximately related to PCM
results if the counting method uses
similar criteria for length and
shape.
conducted in Room T-747 as described in the Asbestos Hazard Emergency Response
Act (AHERA) protocols as amended and regulated by the Environmental Protection
Agency. This protocol uses a one-horsepower leaf blower to simulate worst-case
airborne levels which could be created by personnel disturbing asbestos fibers stuck to
carpeting. It was felt this method would simulate heavy classroom use. The results
exceeded the AHERA limit of an average of 70 structures per square millimeter per
sample using Transmission Electron Microscopy (TEM).
Due to the difficulty in removing asbestos fibers from carpeting, the carpets in Rooms T739 and T-747 were subsequently removed as another asbestos abatement project
using full controls, and replaced. The chairs in T-747 which were covered with soft
cushions also had the cushions removed. Non-porous surfaces such as tables in T-739
and T-747 and the equipment rack in T-747D were re-cleaned. Equipment in T-747D
which had internal fans that probably sucked in asbestos fibers were treated as
asbestos-contaminated and properly disposed. There was no indication that the T-739
Media/ Projection Room was contaminated by any debris, so that equipment was not
disposed. The abated rooms were checked for contamination in accordance with the
abatement specification and the rooms were again available for un-restricted occupancy
on September 7, 2005.
During this initial response period, UW personnel who had scheduled activities in the
rooms were contacted and asked to provide class lists of the personnel who may have
entered room T-739 or T-747 during the period of July 6th, 2005 through August 9th,
2005. These individuals were then contacted, notified of their potential exposure to
asbestos and asked to respond to a questionnaire (Appendix A). This was done to
inform them of the situation and to try to obtain some information from them in order to
determine the extent of possible exposures. Other persons known to have entered the
room (UW employees who entered due to their job requirements) were also added to
the list of people who were requested to fill out the questionnaire. The majority who
were requested to respond were contacted by email (over 1,200), but approximately
100 were contacted through US Postal Service mailings.
In some cases, the scheduler had a list of people who were invited to attend an event,
but did not have a specific roster of those who attended. In these cases, a request to
respond was sent to all who had been invited. (It turned out that many of these
“invitational events” invited the same individuals because the events had common
subjects.)
The questionnaire responses received from possible room occupants, results of the
post-event sampling performed, plus information available in the literature formed the
basis for a health hazard assessment described in a later section of this report.
5
Hazards of Asbestos
The primary concern with exposure to asbestos occurs if microscopically small asbestos
fibers are inhaled deep into the lungs and lodge there. Studies typically involving years
of exposures to large numbers of fibers have shown an increased incidence of lung
cancer and mesothelioma (a cancer of the pleura, or lining of the lungs). Results of
exposures to lower levels and infrequent episodes of exposures are difficult to measure
directly, and the increased risk of cancer is generally considered to be minimal.
Exposure to high levels of asbestos fibers over many years has also been shown to
increase the incidence of asbestosis, which cause a progressive deterioration in lung
function. Also, some studies show there may be an increased risk of developing
cancers in different organs associated with the throat and gastro-intestinal tract if large
quantities of asbestos fibers are ingested.
Some studies have indicated that results may vary depending on the type of asbestos
fiber involved. Some studies indicate that exposure to chrysotile fibers may result in
less risk of lung cancer than from crocidolite or amosite fibers, and that smaller diameter
fibers may increase the risk more than larger diameter fibers. Additional information on
health effects is at www.atsdr.cdc.gov/toxprofiles/phs61.html. The International Agency
for Research on Cancer (IARC) study which determined there was sufficient proof of
carcinogenicity for asbestos provides an excellent review of carcinogenicity studies, and
can be found at www.inchem.org/documents/iarc/suppl7/asbestos.html.
With respect to short-term effects, if large amounts of asbestos were to be inhaled, the
immediate physiological response would be similar to that from inhaling large amounts
of non-reactive dusts. In the situation described in this evaluation, the asbestos
component was minor compared to the sodium bicarbonate amount. The presence of
large amounts of the sodium bicarbonate, which was the predominant component in the
debris, may have been the source of any immediate feelings of throat or eye irritation.
The Material Safety Data Sheet (MSDS) notes that sodium bicarbonate is generally
recognized as safe (GRAS), but also recommends use of goggles and respirators in
extremely dusty environments.
6
Questionnaire Responses
Questionnaires sent to possible occupants of T-747 and T739 during the period of
July 6, 2005 through August 9, 2005 were designed to be either directly input via the
web into a UW Catalyst Tools scoring database or a returned paper copy was entered
into the database by EH&S staff. As of January 31, 2006, 288 responses had been
received, out of approximately 1,320 requests for response, for a 22% response rate.
The most important unexpected response was that “clouds of dust blew into the room,
apparently from the renovation project going on in T-639” during classes. The
individuals noting this were in two classes, Nursing 201 (Growth and Development
through the Life Span) (NURS201A) where dust visibly blew into Room T-747 on three
occasions, and on one occasion among the group of dentistry students taking the block
of classes ORALM 529A (Stomatology) / PEDO 525A (Pediatric Dentistry) / RES D 620
(Comprehensive Treatment Planning in Restorative Dentistry).
The custodians cleaning the rooms noted on their questionnaire responses that some of
them had vacuumed locations in the room when dusty, using vacuums which were not
HEPA-filtered. This could create significant airborne asbestos fiber levels for the
relatively short time that the custodians were in the rooms. None of the custodial staff
questionnaire responses indicated they had vacuumed the Media/Projection Room T747D.
Some questionnaire responses indicated that a few individuals noted feelings of throat
irritation and other symptoms perhaps similar to flu-like symptoms. These symptoms do
not correspond to airborne asbestos exposures per se, but may be due to total dust
levels, or possible irritation of sensitive individuals to high levels of sodium bicarbonate,
or exposures not related to the situation being evaluated. Sodium bicarbonate is
considered as generally safe, but excessive dust levels may cause irritation in some
individuals.
The questionnaire responses from individuals entering the Media/Projection Room
T-747D indicated they frequently noted dust in the room, but no one indicated being in
the room when dust was entering. Also, the exposure periods were generally short for
most people entering the room. Of the 21 responses indicating entrance occurred to
the T-747 Media/Projection Room, the length of time for one entry into the room ranged
from 2 minutes to 60 minutes and averaged 11.8 minutes per entry, with a maximum of
two hours total in the room for those who had multiple entries.
Possible exposure while walking on a debris-contaminated floor in the Media/Projection
room was originally believed to be the worst-case exposure condition due to the large
quantity of dust in the room. It is now believed that the worst-case exposures occurred
to those within the main lecture room T-747 when dust visibly entered during the 3
classes noted above, and to custodial staff operating non-HEPA filter vacuums.
7
Discussion of Potential Exposures
Even though most of the bulk samples reported in Table 2, Results of Bulk Samples
Collected August h, 2005, showed no detectable asbestos, the conservative approach
taken was to assume that since the abrasive material was used to abate asbestoscontaining fireproofing, the debris was likely to contain some asbestos. The limit of
detection for bulk asbestos analysis by PLM is approximately 0.3% to 1% asbestos
content, depending on the experience of the analyst. Samples analyzed as “none
detected” may have been contaminated with small quantities of asbestos (less than
0.3%).
Two air sampling occasions give some scale to possible exposures when estimating
exposures from this situation. On August 5, 2005, two air samples were collected while
the abatement personnel were cleaning the rooms. The samples were submitted for
analysis by PCM, but were evaluated as too dirty to analyze. They were able to be
analyzed by TEM and the results are shown in Table 3. To determine if large quantities
of carbonate from the sodium bicarbonate abrasive were present in the air samples
collected while the rooms were being cleaned on August 5, these filters were also
analyzed for dolomite prior to the TEM analysis.
Table 3. TEM Analyses of Air Samples while Cleaning August 5, 2005
Sample
Sample
Dolomite Asbestos Asbestos Asbestos Asbestos
#,
Content (Fibers per fibers of
Description Content Content
square
(%)
(%)
(%, calc
Air
PCM1millimeter)
from fiber
Volume
equivasizes)
(liters)
lent size
ES-242,
1682
ES-243
4110
Room T-739
while being
cleaned
Room T-747
while being
cleaned
Total
PCMequivalent
fibers
(f/cc)
(f/cc)
83
<0.1
0.003
5.9
0.037
0.089
90
<0.1
0.09
7.1
0.018
0.064
Permissible Exposure Limit (8-Hour time weighted average, fibers longer than
5 microns using PCM procedure) (f/cc)
0.100
1
PCM-equivalent fibers indicates fibers were counted if they were equal to or greater than 5 microns in
length and had a length to diameter ratio of greater than 3:1, as described in Washington Administrative
Code 296-62-077
The carbonate component of the samples is represented by the analyses for dolomite
content, and the high results indicate that the majority of material captured on the filter
was from abrasive residue. The remainder would be organic contaminants such as
carpet fibers and skin flakes, and inorganic contaminants such as soil particles.
Carbonate content in soils in the Seattle area is typically less than 10%.
8
The second applicable air sampling event occurred August 11, 2005 when aggressive
air samples were collected to determine if the carpet could release elevated levels of
asbestos fibers. The samples were analyzed by TEM and the results are shown in
Table 4.
Table 4. TEM Analyses of Air Samples Collected during Aggressive
Treatment of Carpet, August 11, 2005
Sample #,
Air Volume
Sample Location
(liters)
TEM 1857,
1270
TEM 1858,
1224
TEM 1860,
1224
TEM 1868,
1264
TEM 1869,
1264
TEM 1887,
1295
TEM 1897,
1295
TEM 1898,
1254
TEM 1899,
1295
TEM 1900,
1290
In lecture hall T-747, halfway
up aisle, northwest side of
hall
In lecture hall T-747, halfway
up aisle (podium side aisle),
southeast side of hall
By podium of T-747
(structures per
square
millimeter)
PCM1equivalent
asbestos fibers
Total PCMequivalent
fibers
(f/cc)
(f/cc)
845.1
0.058
0.058
1,448.8
0.076
0.076
413.9
0.017
0.026
931.4
0.068
0.073
689.9
0.089
0.089
<702
<0.005
<0.005
<70
<0.005
<0.005
<70
<0.005
<0.005
<70
<0.005
<0.005
<70
<0.005
<0.005
Asbestos
In T-747 Media Projector
Booth
In back third of T-747, about
at the middle of the row
In hallway, to southwest,
across from entry to lecture
hall T-739
In hallway, to northeast, past
alcove to elevator 174
In hallway, at entry to lecture
hall T-733
In hallway, across from west
entry (by podium) to lecture
hall T-747
In hallway, across from north
entry to lecture hall T-747
Permissible Exposure Limit (8-Hour time weighted average, fibers
longer than 5 microns using PCM procedure) (f/cc)
0.100
1
PCM indicates PCM analysis for fibers equal to or greater than 5 microns in length with a length to
diameter ratio of greater than 3:1, as described in Washington Administrative Code 296-62-077
2
The symbol “<” indicates “less than.” The number <70 indicates a value less than 70.
Since these sampling events did not occur during the actual construction-related events,
the actual levels of exposure during those times are not known and can not be
accurately reproduced. There is a range of possible exposure levels during
occupational exposures. The level that Nolan et al, in Risk Assessment for AsbestosRelated Cancer from the 9/11 Attack on the World Trade Center (Journal of
9
Occupational and Environmental Medicine, August, 2005) chose to represent worst
case conditions from asbestos generated during the Trade Center collapse was 50 f/cc,
which was a level measured historically during uncontrolled releases of dust inside
mines and mills where the ore contained 2% to 4% chrysotile asbestos.
The direct reading of asbestos content during the TEM analyses are shown in Table 3.
TEM Analyses of Air Samples while Cleaning, August 5, 2005 indicated <0.1% asbestos
content in the samples. However, by knowing the total mass captured on the filter and
by extrapolating asbestos mass from the number of asbestos fibers times average mass
per fiber, the mass percentage of asbestos in the sample was calculated as 0.006% for
sample ES-242 from room T-739, and 0.06% for sample ES-243 from room T-747.
These calculations show that the dust which blew into the rooms averaged less than 1%
asbestos.
Based on these calculations, it is reasonable to assume that the worst case exposures
for those present when the dust was blown into the rooms were less than 50 fibers per
cubic centimeter (f/cc).
Another assumption is that the best simulation of normal activity in the room when dust
was not blowing in is to use the highest level measured during the cleaning operations
conducted August 5 or the aggressive air sampling episode of August 11, 2005, which
was meant to simulate occupant activity on a contaminated carpet. The highest level
measured of those seven samples collected in T-739 and T-747 was 0.089 f/cc, which
can be rounded up to 0.1 f/cc for easier calculations. This is the assumed worst case
exposure for those who were present in the rooms at times other than when dust was
entering.
In addition, if people were wiping dust off of visibly contaminated surfaces, the samples
collected August 5 are assumed to be probably the better estimate of possible
exposures while the area was being cleaned. The higher of the two sample results on
that date as shown in Table 3. TEM Analyses of Air Samples while Cleaning,
August 5, 2005, was 0.089 f/cc. Assuming levels were 0.1 f/cc makes it easier to
perform calculations.
State of Washington regulatory limits for asbestos exposure are found in Washington
Administrative Codes (WAC) 296-62-07705, Part I-1 – Asbestos, Tremolite,
Anthophyllite, and Actinolite as follows:
(1) Time weighted average (TWA). The employer shall ensure that no employee
is exposed to an airborne concentration of asbestos in excess of 0.1 fiber per
cubic centimeter (0.1 f/cc) of air as an eight-hour time-weighted average (TWA)
as determined by the method prescribed in Appendix A of this part, or by an
equivalent method recognized by the department.
(2) Excursion limit. The employer shall ensure that no employee is exposed to an
airborne concentration of asbestos in excess of 1.0 fiber per cubic centimeter of
10
air (1 f/cc) as averaged over a sampling period of thirty minutes, as determined
by the method prescribed in Appendix A of this part, or by an equivalent method
recognized by the department.
An exposure of 50 f/cc exceeds the excursion limit after 3/5 of a minute (calculated from
30 minutes/50 times higher than the permissible limit). An exposure of 50 f/cc also
exceeds the 8-hr TWA exposure limit after 24/25 of a minute (calculated from 480
minutes/500 times higher than the permissible limit).
The individuals attending the three classes during which dust was observed entering T747 and T-739 were in the room for longer than 3/5 of a minute Based on the worstcase calculations and the application of WAC 296-62-07705(2), the situation in this
report may have exceeded regulatory limits.
11
Evaluation of Possible Exposure Risks
The length of time that different groups may have potentially been exposed to asbestos
contamination are shown in the following tables, based on information from class
schedulers and from questionnaire responses.
Table 5. Approximate Durations of Different Classes and Events in the Rooms
Class/Seminar/Event
Room
# of
Events
Hrs/
Event
Attendees
Est Hrs/
Person
Comparative Medicine Meeting
Continuing Med Ed – Health Care Ethics –
Basics of Ethics Committees
Continuing Med Ed – Health Care Ethics –
Breakout Session DG12
Continuing Med Ed – Health Care Ethics –
Teaching Ethics in a Clinical Setting
Dentistry - DPHS 550E Classes
Dentistry - ORALM 529/PEDO 525/RES D
620 Classes
E&OHS - Dissertation Defense
EH&S – Radiation Safety Class
Immunology - Dissertation Defense
Immunology - U. S. – Japan Immunology
Board Symposium
Jay Horton Lecture, Department of
Metabolism, Endocrinology and Nutrition
Medicine - INTERN Conference
Medicine - MEDEX 451 Breakout Sessions
T-747
T-739
1
1
2
2
19
38
2
2
T-747
2
2
11
4
T-739
1
2
21
2
T-739
T-747
10
28
2.5
0.5 - 3
25
57
25
59.5
T-747
T-747
T-747
T-739
1
3
1
2
1.5
2
3
5 - 10
30 (Est)
27
60 (Est)
147
1.5
6
3
15
T-747
1
2
100 (Est)
2
T-747
T-747,
T-739
T-747,
T-739
T-739
T-739
T-739
T-747
T-747
All
All
All
T-747
T-747
T-739
5
1
1
3
60 (Est)
88
5
3
8
2-8
149
40
1
5
4
9
1
1 - 12
1-2
1-5
1
1
1
4.5
1.5 - 2.5
1
3
0.5
0.1 - 1
0.5 - 2
0.5 - 2
2
2.5
2
32
120 (Est)
21
35
6
12
8 (Est)
9
60 (Est)
60 (Est)
11
4.5
8.5
4
27
0.5
2
1
1.5
2
2.5
2
T-739
5
3
27
15
Medicine - MMEP/UDOC Classes
Medicine - REHAB 538 TU Special Class
Medicine - Resident Teaching Conference
Nursing - NCLIN 302 Video Series
Nursing - NURS 201A Classes
Others – UW Catering
Others – UW Custodial Staff
Others – UW Facilities Services/Support
Others – UW HS HSAS & F Media Support
PAIN Center – Murphy Lecture
Psychiatry Grand Rounds
Public Health and Community Medicine BIOST 580D Special Session
Public Health and Community Medicine HSERV 504S Classes
Total
1,233*
* Some individuals attended multiple events. Also, some organizations maintained a list of invited
guests, but did not know who actually attended the events, nor the total number attending.
12
Based primarily on the responses to the questionnaires, the highest exposures were
likely to have been experienced by the people in the rooms when presumably
contaminated dust was visibly blowing into the rooms and by custodians using vacuum
cleaners without HEPA filters. These levels were assumed to be 50 f/cc as previously
described. Other exposures due to walking on carpet which presumably had asbestos
contamination or due to sitting at desks which may have had some asbestos
contamination were evaluated as lower level exposures, of 0.1 f/cc or lower.
Table 6, Exposure Estimates for Different Groups, provides information selected from
Table 5 for those groups suspected of having the highest potential exposures, restated
to be consistent with the two main categories of exposures – either in the room when
dust blew in (or custodial staff operating a vacuum) or being in the room at other times
when dust was assumed to be present on surfaces, but not being actively blown into the
air. The additive amount of “fiber per cubic centimeter · years” was calculated based
on assumed fiber level times the number of hours of exposure divided by hours per
year.
Table 6. Exposure Estimates for Different Groups
Situation
Approx.
Number
of Hours
/Person
A. People in room with dust blowing in (NURS 201A
Class) – three occasions at three hours for each
occasion
B. People in room with dust blowing in (ORALM
529A/PEDO 525A/RES D 620A Class) – one occasion
C. Custodians vacuuming dust
D. People entering media room
E. Remainder of time that NURS 201A students were
presumed to be exposed
F. Remainder of time that ORALM 529A/PEDO
525A/RES D 620A students were presumed to be
exposed
G. Custodians wiping dust off table tops
H. Worst Case for Nursing Class (A + E above)
I. Worst Case for Dental Classes (B + F above)
J. Worst Case for Custodians (C+ G above)
Assumed Calculated
Exposure
Additive
Level
(f/cc)·years
(f/cc)
(f/cc·years)
9
50
0.051
3
50
0.017
0.25
0.1
18
50
0.1
0.1
0.0014
0.000001
0.0002
56.5
0.1
0.0006
1
N/A
N/A
N/A
0.1
N/A
N/A
N/A
0.00001
0.051
0.018
0.0014
To extrapolate the additive risk for mesothelioma, we used an absolute risk model, as
described by Nolan et al, for the worst case scenario as highlighted in Table 6.
Some of the assumptions used in generating the mesothelioma calculation are given in
Appendix D for clarification in the main part of the report.
13
(1) For mesothelioma, potential observed cases (ObsM) can be calculated by the
following:
ObsM = (RM x ECA x TPOP) / 100
Where in the above equation:
RM is the risk of mesothelioma as a percentage of the total expected mortality.
ECA is the additive exposure to chrysotile.
TPOP is the age-corrected population assumed to be at risk, that is, 35 students
and teachers in the class (from Table 5) which equals 25.0
ObsM = (RM x ECA x TPOP) / 100 =
(0.001 x 0.22 x 25) / 100 =
0.000055 additional mesothelioma deaths, or,
5.5 x 10-5 additional mesothelioma deaths
The absolute risk of mesothelioma from this assumed worst case exposure is then
ObsM / TPOP or 5.5 10-5 / 25 = 2.2 x 10-6
(2) For lung cancer, the potential total number of cases (ObsL) can be calculated from
ObsL = ExpL + (RL x ECA x ExpL) / 100
ExpL is the expected cases of lung cancer, using the assumptions noted earlier.
RL is the risk of lung cancer as a percentage of the lung cancer deaths per
f/cc·years of occupational asbestos exposure.
ECA from above = 0.22 (f/cc)·year
ObsL = ExpL + (RL x ECA x ExpL) / 100
ObsL = 0.7778 + (0.13 x 0.22 x 0.7778)/100 =
0.7778 + 0.00022 additional lung cancer deaths. or
0.7778 + 2.2 x 10 -4 additional lung cancer deaths
The relative risk of additional cases of lung cancer would be 0.00022 / 0.7778 = 2.8 x 10-4
This observed value for mesothelioma (5.5 x 10 -5) and the additive value for lung
cancer (2.2 x 10-4) are much smaller than one. It is expected that out of a group this
size at least one person would come down with mesothelioma and or lung cancer
without this exposure incident. The calculations show that there would not be even one
full additional case from this incident. Therefore, no measurable effect is expected from
the presumed exposures described in this report.
With the assumption that the dust contained asbestos fibers, and the observation that
dust blew into the room while class was in session, it is also obvious that some fibers
would be assumed to have adhered to class members’ clothing. There is no
quantitative data from this incident as to the amount of contamination that could be
expected to adhere to clothing. Reports in the literature (Miller, Schneider et al)
concluded that family members of asbestos workers have suffered cases of
mesothelioma due to asbestos carried home on the workers’ clothing. Some of the
14
exposures may have been from an era when standards were much looser, and the
workers’ clothing was probably visibly soiled and dusty.
None of the questionnaire responses mentioned dust settling onto clothing, but this may
have occurred at low levels. Given the low average concentration of asbestos in the
dust and the assumed likelihood that asbestos fibers adhering to clothing would
gradually be released and diluted by surrounding air, any additional exposures after
leaving the lecture halls is likely to have been much smaller than that received within the
classes and would probably not have been measurable given the background
concentration of asbestos in ambient air.
15
Medical Follow-up Concerns
WAC 296-62-077 requires medical examinations for personnel exposed above
permissible exposure limits for more than 30 days in a calendar year. The WAC
mandated medical examination for asbestos consists of taking a history, checking lung
function, and taking chest x-rays. However, since the number of days when asbestos
was assumed to have exceeded permissible exposure levels was a maximum of 12 for
one custodian and 3 for those attending the nursing course, there is no regulatory
requirement in this case for an occupational medical examination for asbestos.
Based on the exposure incident hazard assessment, no mandatory medical follow-up is
necessary for any of the individuals who entered these rooms during the time the
incident was occurring, since cumulative exposure levels were so low that no medical
effects are considered likely.
Nevertheless, anyone who has questions, about work-related concerns, can obtain
consultation and advice from the Occupational Health Nurse in Environmental Health &
Safety, or Campus Health Service’s Employee Health Clinic, located at Hall Health
Center.
When seeking medical consultation for any health concerns related to this incident,
individuals should take a copy of this report together with a completed copy of the
screening questionnaire with them to their clinic appointment. The documents will be
available on the EH&S web site at www.ehs.washington.edu.
16
Actions to Prevent Recurrence / Additional Follow-up Actions
The University’s Environmental Health and Safety department has determined the key
contributing factors to this incident appear to have been:
•
•
•
•
Inadequate sealing of conduit spaces in the construction zone;
Unanticipated impacts to areas considered outside the construction/containment
area;
Lack of immediate notification by those experiencing impacts; and
Substitution and use of an exterior asbestos removal technique for a previously
planned indoor removal technique.
Possible actions to prevent recurrence of such factors include:
•
•
•
•
•
•
•
•
•
Assure contractors can demonstrate expertise and familiarity with Washington
State requirements for proper safe handling of asbestos. (If contractor or
consultant has not done projects for the University before, they should have to
demonstrate to the University their work will address all University requirements.)
Modify the University’s Professional Service Contract for the Asbestos Consulting
so the asbestos consultant is a more aggressive proponent for the University.
Require a wider area assessment and spot checks of potentially impacted areas,
including all adjacent spaces during the conduct of asbestos projects
Restrict the use of baking soda abrasive blasting for asbestos abatement,
Increase oversight of projects by UW project manager and asbestos abatement
projects by the UW by Asbestos Consultants.
Prior to re-occupancy of any questionable areas, it should be a standard CPO
procedure to contact EH&S
CPO should provide Building Coordinators with specific information on a specific
asbestos abatement project and emergency contact information.. This should be
posted in areas adjacent to, as well as on floors above and below the project.
CPO should clarify requirements for process substitutions during asbestos
abatement activities so that those who have approved original contract
specifications, including but not limited to CPO, FSO, and EH&S review and
approve proposed changes.
If another potential exposure event takes place, take air samples to simulate
exposure conditions before cleaning.
17
Conclusions
During the period of July 6, 2005 through August 9, 2005, construction related debris
entered Rooms T-747 and T-739 of the Magnuson Health Sciences Building. Because a
classroom renovation project, which included asbestos abatement, was underway in
Room T-639, directly below Rooms T-747 and T-739, the debris was assumed to
potentially contain some level of asbestos contamination.
There can be no definitive assessment of exposure levels received by occupants in T747 and T-739 since sampling for asbestos contamination did not occur until sometime
after the actual incident. The results reported in this document thus depend on
secondary data sources.
It can be assumed that individuals who entered the rooms while potential contamination
was present may have received an asbestos exposure above asbestos levels that are
background levels in those rooms. Some individuals attending classes while dust
entered the room were likely to have had exposures that exceeded the regulatory short
term exposure limit for a fifteen minute exposure and the eight-hour time weighted
permissible exposure limit when averaged for a day (Washington Administrative Code
296-62-077). Custodians who operated vacuums in the room for short periods may also
have exceeded the permissible exposure limits.
However, further evaluation of the possible exposures for these occupants indicates
that, even if worst case exposure levels are assumed, the assumed exposures do not
present an identifiable risk higher than normal levels, due to the relatively short
exposure period. Various procedures to minimize the possibility of a situation like this
happening again are being implemented.
For more information about the incident contact: Denis Sapiro, Manager of the
Occupational Health and Safety Office in Environmental Health & Safety can be
contacted at 206-221-4247 or by email at [email protected].
18
References
Hodgson JT, Darnton A. The Quantitative Risks of Mesothelioma and Lung Cancer in
Relation to Asbestos Exposure. Ann Occup Hyg. 2000; 44: 565-601.
Miller A. Mesothelioma in household members of asbestos-exposed workers: 32 United
States cases since 1990. Am J of Ind Med 2005; 47: 458-462.
Nolan RP, Ross M, Nord GL, Axten CW, Osleeb JP, Domnim SG, Price B, Wilson R.
Risk Assessment for Asbestos-Related Cancer From the 9/11 Attack on the World
Trade Center. J Occup Environ Med 2005; 47: 817-825.
Schneider J, Straif K, amd Woitowitz HJ. Pleural mesothelioma and household
asbestos exposure: Rev Environ Health, 1996: 11(1-2): 65-70.
19
Appendix A. Questionnaire
20
21
Appendix B. Pertinent Comments from the Questionnaire Responses
Status (and Event Attended)
Student (NURS201A)
Employee, Student
(NURS201A)
Employee (Research Scientist,
Medicine), Student
(NURS201A)
Observations Concerning Lecture Hall T-747
A light layer of dust was in many areas through out the room, on most of
the desks in the center area of the room up through about 3/4 of the way
to the top. On one morning of class (don't remember which day) a lot of
dust was spraying up through the floor ducts and blowing throughout the
room.
I don't remember the specific dates, however, we were in the middle of
lecture and could hear the construction below. Puffs of dust started to
come up from the floor and fill the air.
I'm not exactly sure when it happened, but I think sometime b/n 7/21-7/28
we were in class and we heard the construction going on below us. I had
class on Tuesdays and Thursdays from 8:30-11:30AM. It sounded like
they were pressure-washing something. Whatever they were doing it was
really loud and our TA was just about to go down to the room below us
and ask the construction workers to stop working as there was a class in
session and it was too loud and distracting. Well, before she did,
everyone in class started noticing huge clouds of chalk-like substances
being blown up from the floor. It was really weird as it was being blown
up from the bottom of the legs of the tables in each of the rows. The little
rubber-like rings around the bottom were literally bouncing up and all
around as this stuff came shooting out of nowhere, it seemed. I
especially was worried about it as a classmate of mine was sitting two
spots over from me and was directly over where it was coming out
from. This material was literally being blown up into her face and she was
trying to fan it away from her but it was kind of hard to escape it as it was
spreading everywhere in the room. My TA was very ticked off about it
and marched downstairs to tell them to stop what they were doing and
that dust was being blown into our classroom and that it could contain
asbestos. So right away they stopped and came upstairs to check it out.
They apologized and said they would fix the problem (they taped up the
areas at which the substance was coming out of).The chalk-like
substance eventually settled right around the base of these leg support
structures. The next few lectures we had in that room before they moved
us to another lecture room, I noticed the white chalk-like powder was still
settled all around the base of the legs all over the classroom.
Student (NURS201A)
My entire class noticed the white powder. It happened more than once
while we were in class. When it became disruptive, my teacher went
down to the room below to inform the workers of the problem.
Student (NURS201A)
I don't recall the date - but I know our class heard loud noises and saw
white powder coming up from the floors, and landing on the carpet and
desks
Student (NURS201A)
after hearing a lot of loud noise for a long time, we (the class) noticed
white powder coming up through cracks around the desks and chairs in
the front right of the room. I can't remember the exact date, but I believe
it was mid to late July.
22
Student (NURS201A)
they were doing construction below us and when they were drilling
sometimes white powder came up through some holes in the floor. our
professor asked them to stop multiple times but it took many requests
before they would stop. also once the white dust was in the air.
Student (NURS201A)
We would hear people working under us(floor beneath us) and see
steam or dust come up from under us. It would vary from each day,
where the white stuff would come from, mostly depends on where the
workers were working at.
Student (NURS201A)
in the floors where the tables were bolted to the ground. white powder
would be seen flying up when there was construction below. it seemed
as if someone was using a powerful machine to clean the ceiling and
consequently blew up white powder into our floor. I cannot recall the time
or date.
Student (NURS201A)
When the construction workers were power washing from below,
something sprayed through the floors. This happened 2-3 times.
Student (NURS201A)
On one occasion I remember white dust coming up from the floor of the
middle of the room. I don't remember the date.
Employee (Research
Assistant, School of Nursing),
Lecturer (NURS201A)
Student chairs and desk surfaces had dust every time we used the
classroom and on several occasions the white dust came shooting
through the floors where the metal support pipes connect the desk tops.
(7/14 & 7/19) Table at front of room ( I used this for papers and
sometimes to sit on while lecturing) pretty much always had white dust
(the chalk dust is yellow) on the surface. On both occasions when the
white dust came shooting through the floors under high air pressure at
the students- I had the students move to another seat and went down
stairs to directly complain to the workers causing it because complaints
to classroom services did not seem to be working to cease the noise and
dust during class sessions. Andre promised the noise and dust would
stop although it did happen briefly one time after that on ? 7/28.
Student (NURS201A)
there were several days in July when our class started ; our class was on
Tuesdays and Thursdays from 8:30 - 11:30 am. We observed white
powder being ejected into the room from the floor upward. I was right
next to it. It lingered in the air for the whole class, in that the room
seemed hazy. Our teacher had to continually go down there and tell them
to stop working, but this continued to happen, for at least 1-2 hours each
class. It tapered off towards the last few days of July.
Student (MEDEX)
I vaguely remember a small amount being present on some of the desks
at various times, dates unknown.
Student (MEDEX)
I recall seeing some white powder one time and making a joke that it
could be from bio-terror; however it was near construction so I thought it
was okay, but don't recall where I saw it.
23
Student (ORALM529A,
PEDO525A, RESD620)
In lecture on day, we heard a sound "like a tea kettle boiling" coming
from an electrical outlet and then white powder (we thought it was smoke
at first) started coming out. The whole class ran to the sides of the room
b/c we thought there was going to be an explosion but then continued on
with class when a worker told us that it was ok to continue.
Student (ORALM529A,
PEDO525A, RESD620)
several dates -- cant recall exact date or time. may have been chalk dust,
I don’t know
Student (ORALM529A,
PEDO525A, RESD620)
At one point, there was a whole bunch of "dust" spraying out at the front
of the room. One of the workers came in and said it was probably just
dust. There was a hissing sound with the dust spraying out.
Assistant Professor
(RESD620), Lecturer
cannot remember. did not observe. rooms are normally very dirty with
some dust on the tabletops. have observed that for many times before
the event.
On July 14th I was sitting in T747 for lecture between 1:30pm and
5:00pm. At some point white powder began coming out of the power
sockets located under the tables. Some had thought that faulty wires
were smoking. We were assured that there was no fire and that we
should remain. Everyday after that I noticed white powder on the table
tops and on the AV equipment in that room.
Student (ORALM529A,
PEDO525A, RESD620)
Student (ORALM529A,
PEDO525A, RESD620)
I'm not sure what day it was, but one day an outlet near the middle of a
row started making noise and exuded a powder, but it seemed more
yellowish. Nothing had happened in the room to trigger it, but the
students moved away before continuing class.
Student (ORALM529A,
PEDO525A, RESD620)
I am not sure which room it was (747 or 739 it was our PEDO class with
Dr. Peterson) A couple times big plumes of dust were coming out of the
ventilation ducts under our desks. We were all concerned and class was
temporarily stopped while we sent someone to check on what was
happening. Many of us in the class thought that it was smoke coming out
of the ducts and we were afraid there might be a fire. One of the
construction workers came in and assured us there were no problems
and we continued with class and the continued plumes of dust and
smoke coming out of the ducts during the class.
Student (ORALM529A,
PEDO525A, RESD620)
I am not sure of the date, but there was a specific incident. During one of
our classes a lot of white dust came out of one of the outlets in the front
of the room and scared everyone in the room. Everyone left but came
back in shortly after.
Student (ORALM529A,
PEDO525A, RESD620)
some white powder came from under the desks during a lecture and
disrupted it. We were told it was nothing to worry about.
Student (ORALM529A,
PEDO525A, RESD620)
Some white stuff spewed from the electrical outlet during one class
period. I don't recall the date.
24
Student (ORALM529A,
PEDO525A, RESD620)
white dust billowed out of some of the fixtures under the desk toward the
front 1/3 of the room in T-747
Student (ORALM529A,
PEDO525A, RESD620)
sitting in lecture, white smoke came out of electrical outlets in the front of
the room and the back of the room.
Employee (Health Physicist 2,
EH&S), Lecturer (RADSafety)
Stuart Cordts Comment: Rick told me verbally that he saw no powder at
the time of his lecture, July 8, 2005
Employee (Senior Lecturer
Emeritus), Lecturer
When I returned after lunch, the room was cordoned off with yellow tape,
and we were assigned to a different room, I looked into our "former" class
room, and saw some white dust on a cabinet.
Student (MMEP/
UDOC/PREMAT 2005)
I think the tables were a bit "dusty"...like it hasn’t been used in a while.
Student (MMEP/
UDOC/PREMAT 2005)
On and around the podium when testing the slideshow late July, I noticed
a light powder which looked like dust. I am not sure if these are traces of
what was found in that room or if it was simply dust. However, when
actually running the slideshow, I sat in the center of the room (close to
the back) and also noticed that the chairs had some of this film on it. I
simply wiped the seat I sat on with a paper towel and disposed of the
paper towel.
Employee (RN2, School of
Nursing) (TA, NCLIN306A)
I'm sorry, I can't really remember. it seemed that the room was dusty, but
I don't remember details as I wasn't suspicious to watch for anything.
Employee (Maintenance
Coordinator, Facilities
Services)
This was on Friday 8/05/05, material was concentrated most heavily in
the projection control room but was noticeable in all areas where
conduits had penetrated the floor into the space below.
Employee (Asbestos
Coordinator, Facilities
Services)
White powder in the AV room of T-747 and along the floor of the west
wall and under the podium. I was conducting inspection for Facilities
Services Asbestos Office.
Employee (AV Staff)
7/20/05: video taping a course PED0520 12-12:30 (This was actually
entered for question 2e)
Employee (Manager,
Classroom Services) (AV Staff
Supervisor)
Friday 8/5/05: noticed small amount around metal plate in front of podium
and metal plate in middle of room. Also noticed some on the floor furthest
from the podium (where the wall meets the floor).
Employee (Custodial/
Maintenance)
on the carpet
Employee (Custodial/
Maintenance)
on the carpet
Employee (Custodial/
Maintenance)
there was no sign of white powder that I could see.
Employee (Custodial/
Maintenance)
I can’t remember. There was dust on the desk that day was 7-11-05
25
Employee (Research
Assistant, School of Nursing),
Lecturer (NURS201A)
White dust on surface of equipment- noise under the floor but no white
dust shooting up from floors like the classroom. 7/14, 26 & 28
Lecturer (NURS201A??)
Before class I was looking for the VCR, which I thought was in the media
room, so I walked back there and in there. There was a white powder all
over everything. It was July 26th. I walked in, looked at equipment,
looked at the fact that there was white powder all around, and then
walked out. I then went back to the front of the room so I probably at
least had had it on my shoes because you could see my footprints on the
floor in media room
Student (MEDEX)
I did observe two students in the booth after lecture hours that really
shouldn't have been there and were basically "caught" when we came in
for an informal study group.
Assistant Professor
(RESD620), Lecturer
did not remember. room is normally dusty anyway
Student (ORALM529A,
PEDO525A, RESD620)
Nearing the end of the quarter I could see dust on the windows and I
thought someone needed to clean in there.
Employee (Health Physicist 2,
EH&S), Lecturer (RADSafety)
Stuart Cordts Comment: Rick told me verbally that he saw no powder at
the time of his lecture, July 8, 2005
Employee (Maintenance
Coordinator, Facilities
Services)
See question 2E, I immediately suspected the presence of ACM, and
suspected that the cause was from the lecture hall below as they were in
the process of asbestos abatement work. I asked classroom services to
close the room and contacted Capitol Projects construction office for the
project manager, as well as my supervisor Sam Tillery.
Employee (Asbestos
Coordinator, Facilities
Services)
Employee (AV Staff)
inspection
Employee (AV Staff)
I was unplugging the audio out from the booth after the course was over,
since I was done video taping
Employee (Manager,
Classroom Services) (AV Staff
Supervisor)
Friday 8/5/05 - Projection booth carpet and surfaces (slide projectors,
data projector, shelf the data projector sits on). I walked into the booth
twice - once when my employee Joe was in there and once to show Don
Romain
Employee (Program Assistant,
Classroom Services) (AV Staff
Supervisor)
I helped an instructor use the LCD I slide projectors, and noticed a layer
of dust over everything in the room. This was on 8/5/05 at around 9:00
AM
Employee (Custodial/
Maintenance)
Vacuuming, dusting tables
It was more towards the end of July that I observed white powder ~ once
before August 4th and again on August 4th
26
Employee (Custodial/
Maintenance)
picking up garbage and dusting tables
Employee (Custodial/
Maintenance)
I was cleaning and vacuuming. I observed white powder but I'm no
sure what it was
Employee (Custodial/
Maintenance)
Q.3d. I don’t remember. Q.3e. Vacuumed, picked up trash, cleaned
counter
Student (MEDEX)
about a wk or so before quarter ended in the afternoon during
lecture.
Why were we not moved when the other lecture halls where
closed?
I am not sure which room it was (747 or 739 it was our PEDO class
with Dr. Peterson) A couple times big plumes of dust were coming
out of the ventilation ducts under our desks. We were all concerned
and class was temporarily stopped while we sent someone to check
on what was happening. Many of us in the class thought that it was
smoke coming out of the ducts and we were afraid there might be a
fire. One of the construction workers came in and assured us there
were no problems and we continued with class and the continued
plumes of dust and smoke coming out of the ducts during the class.
Student (MEDEX)
Student (ORALM529A,
PEDO525A, RESD620)
Student (ORALM529A,
PEDO525A, RESD620)
I don’t remember white dust but these lecture rooms are always
dusty
Student
I don’t remember seeing any powder but we were busy.
Student (Conference: Health
Care Ethics)
No powder or dust.
Student (Conference: Health
Care Ethics)
Tables and carpet had powder on them. Thought it was dust
(construction) at the time.
Employee (School of Medicine
Resident Program), Student
I had to go to the back of the room to the AV area to return a phone
call at some point in July (sorry can't be more specific) but noted
some white dust on the floor.
Student (MMEP/
UDOC/PREMAT 2005)
big dust-like fibers, a little longer than normal
Student (MMEP/
UDOC/PREMAT 2005)
Occasionally, while attending lecture for the SMDEP I noticed a thin
film of powder on the chairs, evident in the contrast of the brown
chairs to the white film on them. I disregarded the film assuming it
was simply dust. Also, as a participant of the Summer Medical
Dental Education Program we had class promptly at 8:30 am, and
were always the first ones to use this classroom.
Student (MMEP/UDOC)
7/19/2005 & 7/22/2005 While we were sitting in the seats I noticed
that the chairs were dusty and so were some of the table tops.
Employee (Maintenance
Coordinator, Facilities Services)
The quantity was not as great as in the other lecture hall but some
of the material appeared to be present in the utility closets at the
front of the room.
27
Employee (Asbestos
Coordinator, Facilities Services)
varied areas in the room conducting inspection
Employee (Custodial/
Maintenance)
on the carpets
Employee (Custodial/
Maintenance)
Employee (Custodial/
Maintenance)
Employee (Custodial/
Maintenance)
inside the room and on the carpet
Student (NURS201A)
It was very frustrating for our professors, who several times made
requests to the construction workers to cease the loud noises and
vibrations. It was only when the white powder started spraying that
they finally stopped.
Employee, Student (NURS201A)
I am glad to see this is finally being addressed, however, it is a bit
upsetting to know that we were allowed to continue with class in
that room when there was a potential problem.
Employee (Research Scientist,
Medicine), Student (NURS201A)
When my TA went down to tell the construction workers to stop
what they were doing and she told them it could contain asbestos,
she was just kidding as she knew they would stop if she said that
though. She told us that and reassured us that it didn't and so we
weren't as concerned. Now with this discovery with the samples in
that room containing asbestos I am very concerned for my
classmate's and my own health. Will we be kept informed on what
is going on with this investigation? I sure hope so!!!
Student (NURS201A)
I am quite concerned. Please let me know if I should contact my
doctor to get a checkup
Student (NURS201A)
Sometime in August I recall that the A/V rack in the back of 747
was taped off and sealed, with warning signs posted on it. What
was known about the asbestos contamination at this time, and why
was the A/V rack sealed off?
Employee (Research Assistant,
School of Nursing), Lecturer
(NURS201A)
I specifically asked the workers if they knew if there was a danger
of asbestos contamination as I know this building has it and they
didn't know- I suggested they find out because they were placing a
number of people at risk with the type of cleaning they were doing. I
was shocked to learn that this was not determined before the
construction started and that classes were not held elsewhere for
the safety of our students and staff.
Student (NURS201A)
Please tell me what is happening with this and what I was exposed
to in order for me to advise my physician as I am medically
compromised. This is essential for me to know,
Student (MEDEX)
Is there anything that we should be concerned about or be
watching for regarding changes in our health? This seems to be
focused on the liability of the university rather than on the danger
the asbestos might present to our well-being.
No I did not see any white dust on the carpet or the dish or table
tops.
I observed white powder but I didn’t know what it was
28
Student (MEDEX)
I'd like to be fully informed of any findings as a result of this
inquiry/investigation.
Student (MEDEX)
During part of the 6 week class, we saw that the room next to our
lecture hall were taped off cautioning for asbestos exposure. Since
the problem was known, where were we not warned that the room
we were spending our days in was also a risk and why weren’t our
lectures moved to another hall? One other comment - I was unable
to wear my contact lenses during those lectures. I don’t know if it
could be due to the asbestos or not.
Student (ORALM529A,
PEDO525A, RESD620)
I hope this helps
Assistant Professor (RESD620),
Lecturer
I was scheduled to give a lecture, arrived at the room to find out
that the AV equipment was not available. Would have been nice to
be informed ahead of time, had to call AV to set up projectors. Lost
at least 30 minutes of lecture time.
Student (ORALM529A,
PEDO525A, RESD620)
We had a pipe leak in the middle of the room that caused a plume
of smoke to enter the room during class
Student (ORALM529A,
PEDO525A, RESD620)
not sure what room I was in when the white dust came out of floor,
it could have been either 739 or 747
Student (ORALM529A,
PEDO525A, RESD620)
I'm rather perturbed that we are finding out about the asbestos
problem now -- not only was the construction noisy and disturbing
to our class but now we find out we've probably been exposed to a
known cancer-causing agent.
Employee (Veterinary
Pathologist), Student
(RADSafety)
Employee (Health Physicist 2,
EH&S), Lecturer (RADSafety)
Please contact me with the results of your risk survey
Employee (Research
Technician), Student (US Japan Immunology Board
Symposium)
Student
The T-739 lecture hall was filled with capacity for this 2 day event
with some attendees sitting on the floor in the side aisles along the
walls
Heard a lot on noise, that sounded like loudly running water, and
various banging and knocking. It was loud enough to be distracting
and disturbing, but I couldn't tell where the noise was originating.
Shortly after our event in the class room the room was closed due
to asbestos.
Student (Conference: Health
Care Ethics)
I was at the UW for the Summer Seminar in Health Care Ethics we had discussion groups every afternoon and they were located in
different rooms on different days - I'm sorry that I can't remember
the room numbers and I've looked through my paperwork and don't
have any record there either...
Student (Conference: Health
Care Ethics)
send me check for one million now and avoid the rush (just joking) I
saw no signs of dust or powder.
29
Student (Conference: Health
Care Ethics)
Don’t exactly recall the room #. T747 or T739 but the response is
the same for either one. (Summer Seminar in Health Ethics) -No
health issues to note.
Student (Conference: Health
Care Ethics)
Probably unrelated - but at the end of this course, I developed
upper respiratory symptoms (hoarseness, wheeze, purulent
sputum, persistent cough) that lasted for over a month - I put it
down to being in crowded seminar rooms all week, doing a lot of
handshaking etc - but it was the first chest cold I had had for years,
and the most symptomatic I had had since childhood. My first sick
day off work in 6 years.
Student (Conference: Health
Care Ethics)
In the last 2 months I have developed a wheezing cough that is
made worse by any particulates or aerosolized smells.
Student (Conference: Health
Care Ethics)
This is extremely concerning information. Please follow up with
exposure info.
Employee (Graduate Student,
Molecular and Cellular Biology)
I hope you will send us a report on possible levels of exposure and
associated dangers when the analysis is complete. Thank you for
the notification!
Student
This is completely ridiculous. There were warning signs on the
classroom next to us saying asbestos on tape. Knowing that there
was a possibility that all 80 of us could have been exposed why
were we not told about this and moved to another classroom.
Employee (Research Scientist,
Microbiology)
During my time spent in T-739, there were periodic loud banging
noises and strong blasts of air coming from the vents in the front of
the room. It distracted both the speaker and the listeners. Should
this be a concern?
no problem noted at the time.
Employee (Professor,
Immunology)
Student
Don't really know if I saw white powder or not in either room.
Employee (Graduate Student,
Molecular and Cellular Biology),
Student
Employee (Program Support
Supervisor, Comparative
Medicine), Lecturer
I am concerned if I inhaled any significant lung irritants. Can
someone tell me if my concern is founded? Thank you.
Employee (Fire Protection
Engineer), Lecturer
I don't recall seeing visible evidence, but then again I wasn't looking
for it.
Employee (Physics Study Skills
Instructor, Office of Minority
Affairs Instructional Center),
Lecturer
I noticed no indication of any contamination during the time I was
there.
Student
Will we be notified of any potential health risks associated with
participation in these rooms?
Nothing stands out to me regarding my time spent in the lecture
hall.
30
Student (MMEP/
UDOC/PREMAT 2005)
Lecturer (MMEP/
UDOC/PREMAT 2005)
Student (MMEP/
UDOC/PREMAT 2005)
Employee (Director, School of
Medicine Office of Multicultural
Affairs), Lecturer (MMEP/ …)
Student (MMEP/
UDOC/PREMAT 2005)
Am I going to be contacted about the results of the exposure? Am I
at risk?
saw nothing out of the ordinary.
Student (MMEP/
UDOC/PREMAT 2005)
I am not sure if this is related or not, but well into mid to late July, I
began to get moderate eye irritation and discomfort. As a contact
lens user, I had to constantly apply rewetting drops to my eyes to
ease some of the discomfort and eventually had to stop wearing
them. Towards late July, the condition worsened were my eyes
started to secrete some thick film that collected at the corner of my
eyes. This was occurring during the duration of time while using T739. After summer, symptoms got better.
Student (MMEP/
UDOC/PREMAT 2005)
My real answer to question 4f is that I don't remember any white
powder although it could have been there. There were ~100
participants in the room and if there were any substance one or
more of them may have noticed it.
I can't say for sure if it was white powder because I figured it was
just dust. I sat in the last few rows in the back for the lectures.
Student (MMEP/UDOC)
Please keep me updated with news on this contamination at the
email address I've provided. Thank you
I did not notice white powder with the naked eye but I did notice my
respiratory problems (cold that did not go away for weeks) did not
end until after I stopped going to the rooms in question.
The SMDEP program through the Office of Multicultural Affairs had
classes through out T wing during all of July. Contact them so they
can contact all the students through out the country.
Employee (RN2, School of
Nursing) (TA, NCLIN306A)
I am without my records of what rooms we were in, but spent the
summer quarter, one day per week in the 7th floor lecture halls
(they varied). the rooms did seem possibly dustier than usual, but I
really don't remember any specifics. I think I would have chalked it
up to rooms not being cleaned over the summer, not being used,
the construction around the t wing, etc. sorry that I don't have
specifics. thanks, I hope that the exposure to room visitors turns out
to have been negligible.
Employee (AV Staff)
When I carried the camera down the stairs in T747, the wheels on
the tripod scoffed the carpet on the way down
It is possible that I went into T747 or T739 during this time frame to
assist clients with faulty equipment or provide other A/V assistance.
I did not find anything scheduled for myself in those rooms, but if a
client calls at the last minute for help, we will go up to the rooms to
assist them.
I was on vacation July 1-8, July 25-Aug 12. Came back 15th. I do
not remember vac, during July 11-22 the first week. I was back I
was doing floor watch(?) on the 6th floor. I did vac 733 before I
went on vac July 25th. During that time I did not see any white dust.
The chalk that was in the lecture halls was yellow not white.
Employee (Manager, Classroom
Services) (AV Staff Supervisor)
Employee (Custodial/
Maintenance)
31
Appendix C. Monitoring Results
The following sampling results are included in appendix C. Click on the report title to view pdf.
Bulk/Surface Contamination of General Areas:
12 Samples collected 8/5/05 in T-747 and T-739
Tape lift samples from hallway, TEM analysis
Airborne:
TEM analysis of 2 samples during cleanup in T-747 on 8/5/05
PCM analysis (clearance) sample after cleanup in T-747 on 8/6/05
TEM aggressive samples (5) in T-747 on 8/12/05
TEM aggressive samples (5) from hallway outside T-747 on 8/11/05
Surface Contamination of Equipment:
Tape lift samples of equipment rack after first cleaning, TEM analysis
Tape lift samples of equipment rack after second cleaning, TEM analysis
Appendix D. Detailed Assumptions and Calculation Explanations
The following information will help with understanding the “Evaluation of Possible Exposure
Risks” section pages 12 through 15.
Some of the assumptions used in generating the mesothelioma calculation were that the debris
was assumed to be contaminated with chrysotile asbestos only and that personnel potentially
exposed were typically 20 years of age.
For mesothelioma, potential observed cases (ObsM) can be calculated by the following:
ObsM = (RM x ECA x TPOP) / 100
(1)
Where:
RM is the risk of mesothelioma as a percentage of the total expected mortality. It was found in
Table 1 of Hodgson and Darnton, adjusted to age 20, to be 0.001
ECA is the additive exposure to chrysotile. The data come from occupational exposure
measurements, so the level noted in Table 6 needs to be corrected for occupational-equivalent
years. Multiplying 0.051 (from Table 6) by 4.38 (ratio of the hours per year total to yearly work
hours) corrects to equivalent occupational (f/cc)·years = 0.22
TPOP is the age-corrected population assumed to be at risk, that is, 35 students and teachers in
the class (from Table 5) times (70-20)/70 assuming age of exposure was at 20 years, which
equals 25.0
32
ObsM = (RM x ECA x TPOP) / 100 =
(0.001 x 0.22 x 25) / 100 =
0.000055 additional mesothelioma deaths, or,
5.5 10-5 additional mesothelioma deaths
The absolute risk of mesothelioma from this assumed worst case exposure is then
ObsM / TPOP or 5.5 10-5 / 25 = 2.2 10-6
The calculation for lung cancer must take into account the existing incidence of lung cancers, so
this calculation determines the relative, additional number of lung cancer cases expected
beyond the pre-existing expected level, as described by Nolan et al, for the worst case scenario
as highlighted in Table 6. To determine the anticipated level of lung cancer, assumptions as
described in Nolan et al were that 8% of cigarette smokers develop lung cancer, 90% of lung
cancers are found in smokers, and 25% of the individuals potentially exposed are smokers. The
typical age once again is assumed to be 20.
For lung cancer, the potential total number of cases (ObsL) can be calculated from
ObsL = ExpL + (RL x ECA x ExpL) / 100
(2)
ExpL is the expected cases of lung cancer, using the assumptions noted earlier. That is, 90%
of the expected cases are in smokers, which is equal to the number of smokers (25% of the
population) times the estimate that 8% of cigarette smokers develop lung cancer, or (90%) of
ExpL = (25%) of TPOP multiplied by (8%), or,
ExpL = (0.25) x (35) x (0.08) / 0.90 = 0.7778
This indicates that even without the possible exposure to asbestos from this incident, it is likely
that perhaps one person from this group would be identified as dying from lung cancer at some
future date.
RL is the risk of lung cancer as a percentage of the lung cancer deaths per f/cc·years of
occupational asbestos exposure. The value of 0.062 specific to chrysotile asbestos exposure
was found in Table 2 of Hodgson and Darnton. To adjust to age 20, that value needs to be
multiplied by 2.1, giving a value of 0.13
ECA from above = 0.22 (f/cc)·year
ObsL = ExpL + (RL x ECA x ExpL) / 100
ObsL = 0.7778 + (0.13 x 0.22 x 0.7778)/100 =
0.7778 + 0.00022 additional lung cancer deaths. or
0.7778 + 2.2 x 10 -4 additional lung cancer deaths
The relative risk of additional cases of lung cancer would be 0.00022 / 0.7778 = 2.8 10-4
These observed value for mesothelioma (5.5 x 10 -5) and the additive value for lung cancer (2.2
10-4) are much smaller than unity. Therefore, no measurable effect is expected from the
presumed exposures described in this report.
33