Document DGmdrBzMXnKYGLOO95x90k0K5
ABZX CORPORATION INDUSTRIAL HYGIENE SURVEY, >
FRICTION PRODUCTS GROUP ' WINCHESTER, VIRGINIA APRIL 19-23, 1976
ORIGINAL* CC*
JO?,
c. B. Mallory C* C. Blackwell, Jr., I-t.D. A. A. Borin E. H. Feierabend M. D. Gidley G. Nicholson M. C. Rauch, R.N. D. K. Rennie J. P. Fagan, IC Industries
ADLX C0P.P0RJ-.T203
\INDUSTRIAL HYGIENE SURVEY FRICTION PRODUCTS GROUP . WINCHESTER, VIRGINIA APRIL, 19-23. I97
PURFOSg
Thi* Industrial Hygisno gorvay was conducted to determine
the sastsat of occupational dicaase exposure to airborne
asbestos# load, and solvent vapors. Recocnsndaticns for.
control are enumerated in the report.
'**
gy?-woc
Of the 48 samples collected for airborne asbast&MIPrttixj^n^ 1
exceeded the present limit of 5 fibers/ml
^Si^tKcXQns
in length, and tventy-six including the thlrtSse
exceeded the 2 fiber limit which is scheduled fa adoption- by /
OSSA in July of this year. The majority of the exposures ~
were confined to Book Preform and Blok Preform with lighter
excursions observed at the cry line operation in Lower com
pounding and at Disc Brake Inspection. Duplicate and tripli-
cato samples were collected at seven of the aforementioned
operations which accounts for 14 of the 48 samples. Averaging
of the multiple samples revealed 8 hour time weighted levels
at three blok preform units of from 5 to 6 fibers/ml- Fiber
counts of multiple sample locations in Eook Preform revealed
average levels of 4 to 5 fiber s/ml. Historically, book preform
levels have been generally lower than those observed during
this survey. The excursions were not anticipated since tho '
installation of the hoods around the preformerfe should have
significantly reduced the fiber counts. The increase may be
attributable to normal ambient variations, but it is likely
that housekeeping and excessive relianco on the systems by
the operators are also factors. In addition, the mix buggies
are not yet ventilated, and floated fibers arc clearly visible
where the operators lean over and scoop mix from the buggies.
Tho two short terra samples taken from the cry line operator in Lower CCompounding reveal that this operator is overexposed if we observe the 2 fiber limit. This obviously arises curing leading of the mix buggies from the hoppors and to e lesecr extent during shifting and transfer c the wheeled containers.
1- -
Tho threo samplos collected at Dice Brake Preform showed an unusual reduction in airborne fibers. Only one of the units (No. 3) has been redesigned to any e>.-tcnt and would not account for the dramatic decline at all units to 0.43, 0.8, and 0.53 fibcro/ml from previous levels above the five fiber limit. Since the asbestos hoppers above the preform machines were not manually filled at any time during the sampling periods, the omission could account for the reduced exposure. Heavy concentrations of airborne oebestos are generated during this phase of the operation.
One otbwr location, DiM' Bxak* Inspection^- va%jfound to ba ^j
above tho 2 ftlber
Inspection^xpoOxn a
}
caused by dust adhering ta the surfadk ofltgflLbfony oedpf
Steps should be taken to reduce this exposure etiBer tBroughl
precleaning of the pads or provision of adequate ;ch4y|s^
f
ventilation. )
All collected asbestos samples were also analyzed for airborne lead. As indicated in Appendix 2, only two of the samplea*. reached or exceeded the Threshold Limit Value of 0.15 ragA&
The locations Involved included Blok Preform No. 15 ana Blok Preform No. 5. Since these were short-term samples, the listed values (Sample 19, .149 ng/M3 and sample 25, .197 mg/^L3)
do not represent time weighted concentrations or averaging over sn 8 hour workday. Tho only inference that can be drawn from the values is that they may be representative of the air borne lead concentrations present during any other short term period during the 8 hour workday. This may or ci2y not be the case. Blok Preform No. 5, which waa campled twice, shewed the aforementioned short term level of .197 tagAt? and an earlier level of 0.137 rog/k3 for an average of 0.167 rag/ll3. Since
both exposure locations were Blok Preform units, it is apparent that further collection system improvements are needed.
Personal samples of printing inks were taken at Blok Finish
Printer No. 2, Strip Finish Band Printer No. 2, and Strip
Finish Printer liachine No. 10. As. anticipated, airborne con
centrations of the cuethyl ethyl ketone solvent in the different inks were minimal, ranging from 2.17 mgAi3 to 59.2 3 mg/bi3
versus the Threshold Limit Value of 590 ng/li3. From the stand
point of a fire and explosion hazard, ambient concentrations
are not a problem since the Lower Explosive Limit is over
53,000 rrxg/M3 in air. However, cooking and open flames in the
immediate vicinity of the printing units should be prohibited.
2- -
Vapors concentrated directly above a cpill or open container of KEK can easily reach or exceed the lower explosive linit.
HEco.^imrD^Trotrs
75-1
Existing exhaust ventilation design at blok preform units excludes- shrouding or hooding which is the only effective way to contain floated asbestos fibers. As discussed in provious reports, each blok preform unit should be completely enclosed by an exhausted enclosure except for required acccs3 openings. If possible, the weigh scale should be incorporated into this enclosure.
75- 2 .
Exhausted enclosures at the b .ok end book preform units should be provided for the mi:: buggies, or the mix should be confined in exhausted hoppers in such a manner that scooping and manual weighing-can be eliminated or minimised.
76- 3 Frequency of clean, up of spilled, scattered aabsstMi nix at blok and book preform should be increaM^^ "rocuus pickup should be used exclusively for this purpose.,}
75- 4
Steps should be taken to reduce exposures at Disc Srak? * Inspection either through precleaning of the pads or provision of adequate local exhaust ventilation. It can be assumed that if one inspector is exposed, others in the immediate vicinity are also subject to exposure.
76- 5
Although exposure levels were low at disc preform during this survey, it is likely that significant exposures still exist at Disc Preform Units No. 1 and No. 2. Hoppers similar to that installed at Disc Preform No. 3 should also be made available at units 1 and 2 to elimi nate manual loading of the raw fibers.
76-6
The dry line operator in Lower compounding should be provided with and required to wear an approved particu late respirator during filling of the nix buggies.
76-7
Ml operators in Blok Preform, Book Preform, and Disc Brake Inspection should be provided with and required to wear approved particulate respirators until ventila tion controls have been proven to be adequate. This is a fundamental protective requirement which should not be further delayed. (Repeat recommendation)
3- -
7G--3
rooting requirements in locations where excessive fiber
levcl^Age. procent ore not being observed, caution
^flggmknould
posted at all approaches to areas con- ^
tainting* excessive concentrations of airborne asbestos fibers. This is an OSHA requirements as set forth in the coda off Federal Regulations, and is listed herain
asr a repeat recommendation dating bac3c to our survey
reports off August 14-18, 1372, October 2-6, 1972, and September 10-14, 1973.
7G-9
Employees are not being notified7 odtheir own excessive
exposure to airborne asbestos so that* they can taker-
appropriate protective measures whether lb fee through '
the consistent use off respire toss or.
*^
habits. Employees should be notified irfVpi
their personal exposure aa soon as practicable*^
later than 5 days of the finding. They, si
advised of the corrective action being take] an OSSA requirement aa aet forth i thebC6ft^h^a4ft^i
Regulations, and is listed herein as a repeat zpbOdBSh-~j
dation dating back to our survey reports of August 14--IS,
1972, October 2-6, 1972, and September 10-14, 1973C 1
DISCUSSION
During the survey, two or more short term samples were collects' at each of several operators, particularly in Book and Blok Preform, to obtain averages off levels throughout the day. These particular locations are listed below vith the actual and averaged values.
LOCATION
ACTUAL LEVELS f ibers/tnl
AVERAGE fibers/W
Book Preform #19 Book Preform- <t2 Book Preform #4 Blok Preform 5 Blok Preform #2 Blok Preform in
c
3.7B and 4.26 4.41 and 6.05 3.56 and 6.55 3.74, 3.01, and 7.10, 4.41, 3nd 5.42 and 6.76
5.19 5.33
4.02 5.63 5.05 5.65 5.61 6.1
It would have been ideal if 5 separata samples could have bean taken ot each location for purposes of closer averaging and to comply with OSHA sampling requirements. However, la this instance, time was limited since some asbestos counting was
dona on site ia addition to sample collection. The above data do show fluctuations, but none are extreme, and it ia apparent that the averages ere reasonably representative of actual 8 hou time weighted exposure levels. The short terra method of samp ling ia necessary when airborne particulate concentrations are elevated. Prolonged sampling at some locations overloads the filter, preventing accurate identification and sizing of fibers during microscopic examination. When this happens, erroneous fiber levels of from 10 to 100 times below actual concentrations may be rsported.
As indicated in Appendix No. 1, book and blok preform samples
continued to show elevated fiber levels, especially when re
lated to the 2 fiber limit schedulod for adoption by OSHA in
July. Since ventilation chances have not resulted in notice
able reduction from levels of December 15-20, 1974, it ia . apparent that sources or points of major dustrelease at each
.
blok and book preform unit have not been adequately ventilated,
Most past survey reports have stressed the need for proper exhaust enclosure of the mix buggies and hand transfer portions of the processes. This need is again reiterated. It is our
understanding that engineering controls are to be installed
at the mix buggy locations in Blok Preform in the near future. These plans should also include Book Preform where hooding
installations have helped to reduce scattering and spillage, but have had moderate effect on airborne fiber concentrations.
A recent Industrial Hygiene survey at Salisbury-FPG has dinclosed preform fiber levels ranging from 0.5 to 1.5 fibers/nxl.
One or two locations were above 2 fibars/cl, but the reasons
for the excursions were easily pinpointed and were attributable
solely to poor work practices. The nix buggies and weigh
scales are provided with exhaust ventilation at the Salisbury
plant which appears to be containing affectively airborne
.
asbestos levels, at least to the 2 fiber level. It is suggestc
that FPG-*7inchester inspect the mix buggy enclosures at
Salisbury and consider adopting some or oil of their principles
of asbestos containment.
.
There appear3 to be no clear pattern of asbestos exposure as it relates to the type of mix being used at the individual work station, careless work habits and/or excessive scatter ing of the nix can be assumed to be a factor, but there are no pronounced variations except for airborne lead levels within the survey data to support this contention. The operator at blok preform No. 5 was selected for sampling because c-f the
5- -
presence ay&gfaisto&, mix on floors, equipment, end clothing, *
ca^6^CW4^fflL,.4act generation curing ccooping and weighing.
The lovcl*.desing three different sampling period^ were 8.74 fibers/mlr 3.01 fibers/ml, and 5.19 fibers/ml. These values ^
do not vary significantly from those encountered at Bore
i
fastidious blok preform operations. This lack of effect of
paroonal variables tends to further indicate that the gourea
of excessive asbestos exposure is common in origin. Remain
ing, heavy sources of exposure at both book and blok prefora
are the mix buggies and the manual operations associated there
with.
""
In relation to tho airborne lead results in Appendix No. 2, excursions above the 0.15 ng/*-3 Threshold Limit Value wera
confined tc two locations in Blok Preform. One of the loca tions was blok preform No. 5 (sample No. 25) which, as pre viously stated, was selected for sampling because of excessive dust generation and poor housekeeping conditions. This opera tor also worked at Blok Prefora No. 3 during the morning hours (sampLe No. 10) where airborne lead levels were high (.135 vag/ii^) but not above the Threshold Limit Value. It
would be aaviscable to provide this operator with instructions a3 to proper work habits and the need for consistent good housekeeping.
Throughout tho plant. It was observed that only a few people were wearing respirators. In known exposure areas, only one man was so equipped. This operator's respirator was not worn continuously during dusty operations, but was only worn when the operator himself felt that protection was warranted. X inspected the respirator after the operator h3d deposited it on a dusty.^inoge, and found it to be dirty, and smudged both inside and oud, and the filter was thoroughly caked with asbestos fiberfi^and particulates.
It is imperative that a respiratory protection program be established in the plant whereby all exposed employees are provided with and required to voar approved, properly main tained respiratory protection. This recommendation has been sot forth in several previous reports. Although respirators are provided on a voluntary basis within the plant, this is not sufficient since virtually all of the exposed employees remain unprotected. To have any positive or lasting effects the program must be implemented cn a mandatory basin. In addition, tho employees should be thoroughly instructed in tho use of the equipment, and a central maintenance program should bo established.
Maintenance is an important phnes of any control procedure, and ia aa true for respirators as it is for ventilation equip ment. No matter her/ veil a roepirator ia designed, hcv good its performance, it cannot give satisfactory protection unless it 33 maintained in good condition. This is one of the most frequently neglected factors, particularly with routinely used respirators. The operations of a maintenance program, including frequent inspections, cleaning, replacing, or re pairing worn or deteriorated parts, and storage, should be centralized. They should also be cuperviced carefully by a responsible and capable person sines proper care and maintenance requires a thorough knowledge of the devices.
All routinely used respirators should be inspected frequently. The tightness of connections 3hould be checked, as well as the condition of the facepiece, exhalation and inhalation valves, connecting tubes and/or cartridges, and ennnisters.
Respirators should be cleaned after each use, and they should be collected at a central point at the end of each shift for cleaning and inspection. Each employee's respirator should bear some sort of identification, such as his initials or clock number. When a worker receives a respirator, he should be briefed on the cleaning procedure and assured that he will always get the same device. If the respirators are serviced between shifts, only one respirator per worker is needed. If the cleaning is done during a shift, each worker will require two respirators. When not in use, the respirators should be stored in clean cabinets at convenient locations in the work area. As long as each respirator is assigned to only one person, there is no reason to require special sterilizing. Scrubbing with warm water and soap, rinsing, and air drying is adequate. When the respirator is used by only one indivi dual, a practical method of cleaning is as follows:
'
1. Remove the filter or cartridge and discard.
2. Wash in detergent or soap in warm water.
3. Rin3a completely in clean, warm water.
4. Air dry the device Ln a clean area.
5. Inspect the valves, headstraps, and other parts; replace with new parts if defective.
7- -
6. Insert now filters or cartridgoo/ make cure tha Eaal is tight.
7. Place in a plastic bag for storaga.
After cleaning, inspection, and necessary repair, the respira
tors ehould be stored ir, dustproof containers, away from sun
light, heat, extreme cold, and excessive moisture. Plastic
'
bags are adequate for routinely used respirators. They should
not be stored in clothes lockers or tool boxes, care should
be taken to see that they are packed or stored so that the
rubber facepiece and exhalation valve will rest in a normal
position and function will not be impaired by the rubber
setting in a bent or twisted position.
CONCLUSIONS
Housekeeping had been improved at several locations through out the plant, particularly in Lower and Upper Compounding. Further improvement is needed in Elok and Book Preform. .
Significant asbestos exposures are limited to tvo depertawnt*where design and installation of exhaust equipment are under-- .. way. Efforts should be concentrated on ventilating mix buggies and ancillary manual operations in both Ecok and Blok Prefers. Interim protection in the form of respirators should be provided for the operators. Use of the devices should be a condition of employment in these two areas.
Isolated asbestos exposures at Disc Ercke Inspection and the dry line operation in Lower Compounding require engineering control. Interim protection in the form of respirators should be provided for the operators.
I would like to thank 5ob Erovn and Charles Hallory for their consideration and support during the course of the survey.
G/30/76
ABEX CORPORATION INDUSTRIAL hygiene survey
GLOSSARY
cfm
- cubic feet per minute
Daily noise
dose
- A numerical expression of the total noise exposure an employee receives during the day. if the daily noise dose exceeds 1.00, the noise exposure to the employee is excessive.
dBA
- Decibels symbol denoting the relative intensity of sound pressure levels (re: 0.0002 dyne/square cent
meter)
.
f pm . GRA mg/frl^
-- feet per minute -- General Room Atmosphere *- milligrams per cubic meter of air
'
MS# >pcf
NIOSH approved
-- Medical Study No.
'
-- million particles per cubic foot of air
-- Approved by the National Institute for Occupationa Safety and Health
OBZ ppm
-- operator's Breathing Zone -* parts per million by volume
PS TLV Ventilationrv-
- Personal Sample
'
- - Threshold
Limit
Value
for
an
8
hour 1
daily exposure
- - The terms ventilated,,, ventilating, or exhaust impl the use of mechanical means such as a fan for air
movement unless otherwise noted.
'
CONVERSION CHART DAILY NOISE DOSE/8 HOUR EXPOSURE
TO dBA/8 HOUR EXPOSURE
*
Daily Noise
Dose/8 hr.
dBA/8 hr.
0.50
85 '
1.00-fOSHA MAX. LIMIT--------> 90
1.14 1.33
91 92
1.50
93
1.71
94
2.00
95
2.28
96
2.67
97
2.99
98
3.43 ..
99
4.00
100
4.57
101
5.33
102
6.01
103
6.83 8.00 r 8.88. _
104 105 106-
;
' '
10.00 11.42 .
107 108 . .
13.33 16.00
109 110
17.17 20.00
111 112
22.85 26.66"
113 114
32.00
115
Permissible Employee Work Exposure Time
16 hours __ 8 hours
7 hours ' 6 hours
5.33 hours 4.67 hours 4 hours 3h hours 3 hours 2.67 hours 2.33 hours .. ; 2 hours 1.75 hours 1.50 hours 1.33 hours 1.17 hours 1.00 hours 0.-90: hours 0.80 hours 0.70 hours 0.60 hours 0.50 hours 0.45 hours ' 0.40 hours 0.35 hours 0.30'hours Less than 0.25
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