Document v65ZLa7wrgvr7Mb83k6KXOVMZ

ABZX CORPORATION INDUSTRIAL HYGIENE SURVEY FRICTION PRODUCTS GROUP WINCHESTER, VIRGINIA APRIL 19-23, 1976 ORIGINAL: CC: C. B. Mallory C. C. Blackwell, Jr.* H.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 INDUSTRIAL KYGICi-IE SURVEY FRICTION PRODUCTS GROUP . WINCHESTER, VIRGINIA -APRIL 19-23, 1976 PURPOSE This industrial Hygiene survey was conducted to determine the extent of occupational disease exposure to airborne asbestos, load, and solvent vapors. Recommendations for. control ere enumerated in the report. Of the 48 samples collected for airborne asbestos, thirteen exceeded the present limit of 5 fibers/ml greater then 5 microns in length, and tv^nty--six including the thirteen noted above, exceeded the 2 fiber limit which is scheduled for adoption by OSHA in July of this year. The majority of the exposures were confined to Book Preform and Blok Preform with lighter excursions observed at the dry line operation in Lower Com pounding and at Disc Brake inspection. Duplicate end tripli cate 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 fibezs/ml. Fiber counts of multiple sample locations in Book 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 preformerfe should have significantly reduced the fiber counts. The increase may bo attributable to normal ambient variations, but it io likely that housekeeping and excessive reliance on the systems by the operators' are also factors. In addition, the mix buggies am not yet ventilated, and floated fibers are clearly visible where the operators lean over and scoop mix from the buggies. The two ehort term samples taken from the cry line operator in Lower CCoppounding reveal that this operator io overexposed if we observe the 2 fiber limit. This obviously arises curing loading of the mix buggies frcca the hoppers and to c lesser extent during shifting and transfer cf the wheeled containers. . -1- Tbo threo oanplos collected at Dice Erake Preform zhoxed an unusual reduction in airborne fibers. Only one of the units (No. 3) has been redesigned to any extent 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 asbestos are generated during this phase of the operation. One other location. Disc Erake Inspection, was found to be above the 2 fiber limit. Inspection exposures are generally caused by dust adhering to the surface of the brake pads. Steps should be taken to reduce this exposure either through precleaning of the pads or provision of adequate exhaust ventilation. All collected asbestos samples were also analyzed for airborne lead. As indicated in Appendix 2, only two of the samples reached or exceeded the Threshold Limit Value of 0.15 rug/fa-*. 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 n>g/M3 ana sample 25, .197 mg/ii3) do not represent time weighted concentrations or averaging over an 8 hour workday. The 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 was sampled twice, showed the aforementioned short term level of .197 mg/W* ana an earlier level of 0.137 mg/H3 for an average of 0.167 reg/ti3. 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 Hand Printer No. 2, and Strip Finish Printer Machine No. 10. As.anticipated, airborne con centrations of the methyl ethyl ketone solvent in the different inks were minimal, ranging from 2.17 mg/Vl3 to 59.23 mgAP versus the Threshold Limit Value of 590 mg/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 mg/to3 in air. However, cooking and open flames in the immediate vicinity of the printing units should be prohibited. -2- Vapors concentrated directly cbove a spill or. open container of KEK can easily reach or exceed the lower explosive limit. RECO>g^Jrt^TI0tTS 76-1 Exieting 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 requirod access openings. If possible, the weigh scale should be incorporated into this enclosure. 76-2 , Exhausted enclosures at the blok end book preform units should be provided for the mix buggies, or tha 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 asbestos nix at blok and book preform should be increased. Vacuum pickup should be used exclusively for this purpose. 76--4 Steps should be taken to reduce exposures at Disc Brake Inspection either through precleaning of tha pad3 or provision of adequate local exhaust ventilation. It can be assumed that if one inspector is exposed, others in the immediate vicinity ere 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 Prcforn 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 Bhould be provided with and required to wear an approved particu late respirator during filling of the mix buggies. 76-7 ~ All operators in Blok Preform, Book Preform, and Disc Brake Inspection should be provided with and required . to v/oar approved particulate respirators until ventila tion controls have been proven to be adequate. This io a fundamental protective requirement which should not be further delayed. (Repeat recommendation) -3- 76--3 Footing requircn-cnts in locations vhore excessive fiber levels are present ore not being observed. Caution signs should be posted at all approaches to areas con taining excessive concentrations of airborne asbestos fibers. This is an OSHA requirements ax set forth in the Code of Federal Regulations/ and is listed heroin 33 a repeat recommendation dating back to our survey reports of August 14-16, 1972, October 2-6, 1972, and September 10--14, 1973. 7G-9 Employees are not being notified of their own excessive exposure to airborne asbestos so that they can taka appropriate protective measures whether it be through the consistent use of respirators or more careful work habits. Employees should be notified in writing of their personal exposure as soon as practicable, but not later than 5 days of the finding. They, shodld also be advised of the corrective action being taken. This is an OSHA requirement as set forth in the Code of Federal Regulations, and is listed heroin as a repeat recoraoendation dating back to our survey reports of August 14-18, 1972, October 2-6, 1972, and September 10-14, 1973. DISCUSSION During the survey, two or more short term samples were collected at each of several operators, particularly in Book and Blok Preform,to obtain averages of levels throughout the day. These particular locations are listed below with the actual and averaged values. . LOCATION Book Preform #19 Book Preform #2 Book Preform *4 Blok Preform #5 Blok Preform #2 Blok Preform #7 o ACTUAL LEVELS fibers/ml 3.78 and 4.26 4.41 and 6-G5. 3.56 and 6.55 - 8.74, 3.01, and 5.19 7.10, 4.41, and 5.33 5.42 and 6.76 AVERAGE flbers/ml 4.02 5.63 5.05 5.65 5.61 ' 6.1 It would have been ideal if 5 separate samples could nave been taken at each location for purposes of closer averaging and to comply with OSHA sampling requirements. However, in this instance, time was limited since 3orre asbestos counting wan dona on site in addition to sample collection. The above data do show fluctuations, but none are extreme, and it is apparent that the averages ere reasonably representative of actual 8 houtime weighted exposure levels. The short terra method of samp-- * ling is necessary when airborne particulate concentrations ere elevated. Prolonged campling at some locations overloads the filter, preventing accurate identification and sizing of fibers during microscopic examination. Mien 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 changes have not resulted in notice able reduction from levels of December 16-20, 1574, it is . apparent that sources, or points of major dust r.eleasa at each blok and book preform unit have not been adequately ventilated. Kost 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 aro to be installed at the mix buggy locations in Blok Preforra 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-PPG has dis closed prefern fiber levels ranging from 0.5 to 1.5 fibers/ml. One or two locations were above 2 fibers/cl, but the reasons for the excursions were easily pinpointed and were attributable solely to poor work practices- The mix buggies and weigh ' scales are provided with exhaust ventilation at the Salisbury plant which appears to be containing effectively airborne . asbestos levels, at least to the 2 fiber level. It is suggested that FPG-Winchester 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 as it relates to the type of mix being used at the individual work station. careless work habits end/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 of asbestos mix on floors, equipment, end clothing, end excessive duct generation curing scooping and weighing. The levels during three different sampling periods were 8.74 fibers/ral, 3.01 fibers/ml, and 5.19 fibers/ral. These values do not vary significantly from those encountered at more fastidious blok preform operations. This lack of effect of parsonal variables tends to further indicate that the source of excessive asbestos exposure is common in origin. Remain ing, heavy sources of exposure at both book and blok preform 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 Threshold Limit Value vera confined to 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 Elok Preform No. 3 during the morning hours (sample No. 10) where airborne lead levels were high (.135 rog/K^) but not above the Threshold Limit Value. It would be adviscable to provide this operator with instructions as 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. I inspected the respirator after the operator h3d deposited it on a dusty ledge, and found it to be dirty, and smudged both inside and out, and the filter was thoroughly caked with asbestos fibers and particulates. It is imperative that a respiratory protection progran be established in the plant whereby all exposed employees are provided with and required to wear 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 basis. In addition, the employees should be thoroughly instructed in the use of the equipment, and a central maintenance program should bo established. Maintenance Is an important phnce of any control procedure, . and is aa truo for respirators os it is for ventilation equip ment. No matter how well a roepirator is designed, hcv good it3 performance, it cannot give satisfactory protection unless it 5s 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 ra pairing worn or deteriorated parts, and storage, should be centralized. They should also be supervised carefully by a responsible and capable person since proper care and maintenance requires a thorough kno-.fledge of the devices. Ail 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 cannisters. 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 ba 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 storod 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 followst ' 1. Remove the filter or cartridge and discard. c 2. Wash in detergent or soap in warm water. 3. Rin3Q completely in clean, worn water. 4. Air dry the device in a clean area. 5. Inspect the valves, headstraps, and other partsr replace with new parts if defective. 6. Insert now filters or cartridges; make cure the eeal is tight. 7. Place in a plastic bag for storago. After cleaning, inspection, and necessary repair, the respira tors should "be stored in du3tproof 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 arc packed or stored so that the rubber facepiece and exhalation valve will rest in a normal position end function will not be impaired by the rubber setting in a bent or twisted position. CCNCLUSIOKS 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 two departments 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 Preform. 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 thank Bob Brown and Charles Mallory for their consideration and support during the course of the survey. C/3 0/76 K. David Gidlcy, Certified / Industrial Bygier.iet 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 dailynoise 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 centi meter) . f pin - feet per minute GRA - General Room Atmosphere mg/M-3 - milligrams per cubic meter of air MS# >pcf . - Medical Study No. ' - million particles per cubic foot of air NIOSH approved - Approved by the National Institute for Occupational Safety and Health OBZ ppm PS TLV Ventilation- - Operator's Breathing Zone ' - parts per million by volume - Personal Sample - Threshold Limit Value for an 8 hour daily exposure f - The terms ventilated/x, ventilating, or exhaust imply 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 ' )aily Noise >ose/8 hr. 0.50 dBA/8 hr. 85 ' l.OO-fOSHA MAX. LIMIT-------) 90 1.14 1.33 1.50 91 92 93 . . ' 1.71 2.00 94 95 2.28 2.67 2.99 96 97 98 : 3.43 .. 4.00 4.57 5.33 99 100 101 102 .. 6.01 103 6-83 8.00 * 8.88. ^ 10.00 11.42 13.33 16.00 17.17 20.00 22.85 26.66" 32.00 .. 104 105 : 106 - :: 107 108." 109 110 111 112 113 114 115 '' ' . 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