Document yrwR19bpQZNBkqZ1qmRQ9aE63

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 CORPORATION IOTUSTRIAL HYGIENE SURVEY \FRICTION PRODUCTS GROUP . WINCHESTER, VIRGINIA APRXL 19-23, 1978 PURFOSg Thi* Industrial Hyjisno gorvay was conducted to determine the ecteot of occupational disease exposure to airborne asbestos# lead, and solvent vspox*. Recommendations for. control are enumerated in the report. '** SD?-?^-RY ' *** " 'v 1 . . Of the 48 samples collected for airborne asbestltiflf$Stixttfg^ ! exceeded the present limit of 5 fiber s/xnl g in length, and twenty-six including the thfr^enKl^^^bave^r^ exceeded the 2 fiber limit which is scheduled faKadoptioo* 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. Duplicato and triplicato 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 flbers/ml. Fiber counts of multiple sample locations in Eook Preform revealed average levels of 4 to 5 fibers/ml. Historically, book preform levels have been generally lower than those observed during this survey. The excursions were not anticipated since the ' installation of the hoods around the prefornerh should have significantly reduced the fiber counts. The increase may be attributable to normal ambient variations, but it is likely that housekeeping and excessive reliance on the systems by the operators are also factors. In addition, the mix buggies uro not yet ventilated, and floated fibers arc clearly visible where the operators lean over and scoop mix from the buggies. The two short terra samples taken from the cry line operator in Lower Compounding reveal that this operator is overexposed if we observe the 2 fiber limit. This obviously arises curing lending of the mix buggies freer the hoppers and to e lesecr extent during shifting and transfer cf the wheeled containers. 1- - Tho threo aamplos collected at Dice Brake Preform showed an unusual reduction in airborne fibers. Cnly one of the units (NO. 3) has been redesigned to any e>cnt 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. On* otter locatlonr DiM'Brak* InBfctioajg va%j|ound to ba ^J above th* 2 tflber Insp*ctiow*xpoMMjim canaj^lY* } caused by dust adhering ta the r-Pa^S- ce*^p| Steps should be taken to reduce this exposure eiftbeir tfirougl^ precleaning of tha pads or provision of adequate*exha^st^ f ventilation. ) All collected asbestos samples were also analyzed for airborne lead. As indicated in Appendix 2, cnly two of the sampler*, reached or exceeded the Threshold Limit Value of 0.15 rag/U^. The locations Involved included Blok Preform No. 15 and Blok Preform No. 5. Since these were short-term samples, the listed values (Sample 19, .149 reg/M^ and sample 25. .197 ngAt?) do not represent time weighted concentrations or averaging over an 8 hour workday. Tho only inference that can be drswn from the values is that they may be representative of the air borne lead concentrations present during any other short term period during tha 8 hour workday. This may or ci2y not be the case. Blok Preform No. 5, which was campled twice, showed the aforementioned short term level of .197 tagAt? and an earlier level of 0.137 rogA*? for an average of 0.167 ragAt? * 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 l-iachine No. 10. As.anticipated, airborne con centrations of the methyl ethyl ketone solvent in the different inks were minimal* ranging from 2.17 mg/l-P to 59.2 3 rvgAi^ versus the Threshold Limit Value of 590 ragAt*. From the stand point of a fire and explosion hazard, ambient concentrations are not a problec since the Lower Explosive Limit is over 53,000 rng/M^ in air. However, cooking and open flames in the immediate vicinity of the printing units should be prohibited. 2- - vopcrs concentrated directly above a cpill or open container of KEK can easily reach or exceed the lower explosive Unit. HKCO.^ilb^TIOITS 76-1 Existing exhaust ventilation design at blok preform units excludes- shrouding or hooding which is the only effective way to contain floated oobo3tos fibers. As discussed in provious reports, each blok preform unit should be completely enclosed by an exhausted enclosure except for required access openings. If possible, the weigh scale should be incorporated into this enclosure. 75- 2 . Exhausted enclosures at the h '.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 asbestocj mix at blok and book preform should be lncreatej^;"yLcuur pickup should be used exclusively for this purpose^' 75- 4 Steps should be taken to reduce exposures at Disc Srak? * Inspection either through precleaning ot 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 v/cai 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 recocmsndation) 3- - 7G--3 rooting requirements in locations whore excessive fiber Icvel^ara. prnccnt arc not being observed. Caution *u 1d be posted at all approaches to areas con- ^ tailing* excessive concentrations of airborne asbestos fibers. This is an OSHA requirements as set forth in the Code of Federal Regulations, and is listed heroin aar a repeat recommendation dating bac3c to our survey reports of August 14-18, 1372, October 2-6, 1972, and September 10-14, 1973. 7G-9 Employees are not being notified' oftheir own excessive exposure to airborne asbestos so that*they can taker- ^ appropriate protective measures whether it fee through the consistent use of respiratose or * habits. Employees should be notified irfVpi their personal exposure as soon as practicable*' later than 5 days of the finding. They, si advised of the corrective action being take; an OSEA requirement as set forth is* that < Regulations, and is listed herein as a dation dating back to our survey reports of August 14--IS, 1972, October 2-6, 1972, and September 10-14, 1975C 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 iaverages of levels throughout the day. These particular locations are listed below vith the actual and averaged values. LOATOftT ACTUAL LEVELS fibers/m! ' AVERAGE fibers/ral Book Preform #19 Book Preform- #2 Book Preform #4 Blok Preform #5 Blok Preform #2 Blok Preform #7 . 3.78 and 4.26 4.41 ana 6.05 3.56 and 6.55 3.74, 3.01, and 5.19 7.10, 4.41, and 5.33 5.42 and 6.76 4.02 5.63 5.05 5.65 5.61 6.1 It would have been ideal if 5 separate samples could have bean taken ot each location for purposes of closer averaging and to comply with OSHA sampling requirements. However, in this instance, time v/as limited since some asbestos counting was dona on sita in addition to sample collection. The above data do show fluctuations, but none arc oxtrene, and it ia apparent that the averages are reasonably representative of actual 8 hou tine 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 reported. 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, 1374, it is . apparent that sources or points of major dust release 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 ia our understanding that engineering controls are to be installed at the mix buggy locations in Blok Preform in the near future, The3e 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 dis closed prefers fiber levels ranging from 0.5 to 1.5 fibers/nl. One or two locations were above 2 fiber s/cl, but the reasons for tha excursions were easily pinpointed and were attributable solely to poor work practices. The nix buggies and weigh scales ore 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-f?inchester inspect tbs mix buggy enclosures at Salisbury and consider adopting some cr all of their principles of asbestos containment. There appears to be no clear pattern of asbestos exposure os it relates to the type of nix 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 so2^f$csto, eix on floors, equipment, end clothing, * ci^,(^jcJMkwL,.4uct generation curing scooping and weighing. * Th* levels, ditsing three different sampling period^ were 8.74 fibers/ml ,- 3.01 fibers/ml, and 5.19 fiberc/ml. These values ^ do not very significantly from those encountered at core / fastidious blok preform operations. This lack of effect of parsonal variables tends to further indicate that the oource of excessive asbestos exposure is cocnaon 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 the airborne lead results in Appendix No. 2, excursions above the 0.15 agAi* Threshold Limit Value were confined tc two locations in Blok Preform. One of the loca tions was blok preform No. 5 (cample No. 25) which, as pre-- viously stated, was selected for sampling because of excessive duct goner at ion and poor housekeeping conditions. This opera tor also worked at Blok Preform No. 3 during the morning hours (sample No. 10) where airborne lead levels were high (.135 rog/l^) 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.^lndge, and found it to be dirty, and smudged both inside and trail, and the filter was thoroughly caked with asbestos fibe^tt^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 wear approved, properly main tained respiratory protection. This recoranendation 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 basic. In addition, tho employees should be thoroughly instructed in tho use of the equipment, and a central maintenance progran should ba 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 cartridges; make cure the eeal is tight. 7. Place in a plastic bag for storaga. After cleaning, inspection, and necessary repair, the respira tors should be stored in dustproof containers, away from sun light, heat, extreme cold, and excessive moisture. Plastic ' bags axe adequate for routinely used respirators. They should not be stored in clothes lockers or tool boxes, care should be talcen 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 arc limited to tvo department#where design and installation of exhaust equipment are under- .. way. Efforts should bs concentrated on ventilating mix buggies and ancillary manual operations in both Book and Elck 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 Erake 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 thrnk 5ob Erowrj and Charles Hallory for their consideration and support during the course of the survey. 6/30/76 SUHVZYED 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/M^ -- feet per minute -- General Room Atmosphere -- milligrams per cubic meter of air ' MStt >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 PS TLV Ventillaattiioonn*. - Operator's Breathing Zone ' - parts per million by volume - Personal Sample - Threshold Limit Value for an 8 hour daily exposure 1 - 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. 0.50 1.00-fOSHA MAX. 1.14 1.33 1.50 1.71 2.00 2.28 2.67 2.99 3.43 .. 4.00 4.57 5.33 6.01 6.83 8.00 r 8.88. _ 10.00 11.42 . 13.33 16.00 17.17 20.00 22.85 26.66" 32.00 dBA/8 hr. 85 ' LIMIT-------> 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106- ; 107 108 . . 109 110 111 112 113 114 115 * ' ' 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 O E- SB *3 A . <o - - CU - fc<- o ocr> c o o \ 0 CM 1 >1 5.^ f^- CM \ in w r-4 r S-5 0 Q a> W M **4 N = iiti>< -4 .. 94 *4 3 cH/l 44 CM >< 3W H < Z > y Qc 04 VI 03 gw o oc VH M -4 c 0 a u 0 H 4J o s lE- C y cu a > a Sf o o c Cl a -4 4J Cl d 5 O M a 44 44 Q a. a uc W VI <0 3 C o Vi 55 cu 0 A Vi cu A < c 2 01 o 4J a o Q cm ra VI Ci a Cl o c >i 4J M 0 a cH d VI O H e H a rH 3 O a ^0 3 <2 O o s a o o z o C5 o W 0 Q I Cl M o c o u a cn 4? <? c\ --( CM a 2I U r-4 Om c 44 m o H 4J o w* CU o (0 o X 83o a C9 o r* c\ m cn m CM cn cn o cn CM c e 2I u m n r-4 O in 0 m 44 m 44 in ao w vi ao ao 3 II OX SI CM o io r-4 a o aa H ci m ci a P- VO l c 4? 43 i-4 -4 4vk w o 44 O V4 a CM'k H cJ vi iknk CM a I M i-4 Q 2 VI *-4 1o 2 44 VI C3 >4 m o Vi Q ei Wrl o 44 <y in in O 4 a m tn 0 g w m Cm O Cu o M 81 O 44 O m w a 44 a CM O o 44 m| m in vi 0* O w a M o &0 XX s0 X o O -4 a SI SIX o o a JJ C a 23 X H *>45 o r-4 a 2a 2 xa XO X iia 's-- ^o I--I > to 44 VI O -H E-* < scn CU o 4? 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