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VI t- TO NAM| S. C. Enters PROM SAMI L. P. Gendernalik O INTtl COMPANY CORPISPONDINCK -- eooc "CAT Managwr------------Friction Products rDivision \cal Novtnbr 28 y lc W.ANT OTStCl Trenton Chemical ocrr oivi*io. Industrial Hygiene Personnel H.ANT omcK Chrysler Center tuuccr Asbestos Survey From November 7 - 13, 1972 a survey was made of the exposure of workers to asbestos dust in the Friction Materials Build ing, together with a study of the ventilation systems involved in the various processes. The results obtained are shown in the attached tables* Table I should be maintained in your files for a minimum of three years as required by OSHA standards under Section 1910.93a (,i)(l). EXHIBIT7; Discussion :;S*CCHR-32 In general, no exposures were found in excess of the current threshold limit value. One area was found, however, in which the exposure to asbestos dust is above the threshold limit value scheduled to become effective on July 1, 1976. This was in the batch-mixing area, where loading and unloading of the #4 mixer, a dry mixer, resulted in an exposure to asbestos dust of 4.3 fibers per cubic centimeter of air. The hood at the unloading station for the #4 mixer maintained a capture velocity of only 25-50 feet per minute. This hood should be redesigned to provide a minimum capture velocity of 150 feet per minute. In addition, large amounts of dust are generated while the emptied weigh-hoppers are being removed from the hoist at the loading station for the #4 mixer. An overhead slot-type hood should be installed at the loading station to provide a minimum capture velocity of 100 feet per minute, and the weigh-hoppers should be covered before removing them from the hoist. Several defects were noted in the ventilation systems in other areas of the plant. The dust collector for the ventilation system serving the batch mixers, which is located near the P-Grade Rolling machine in Bay 5-3 of the Extruder Room was observed to generate a large amount of dust during shakedown. Although shake-down was done during a normal work break, when no one was in the area, the dust cloud generated persisted in the air even after the workers returned to the area. Hence, it is recommended that consideration be given to enclosing this dust collector and placing the enclosure under negative pressure, to alleviate this source of exposure. no -nr* -2- The hooding on the Edge Grinder (Vertical Belt Sander) in Bay E-8 of the Brake Shoe Finishing area was observed to provide unsatisfactory capture of the dust generated. This hooding should be redesigned to meet OSHA specifications as shown in the drawing attached to this report, and any other belt senders currently in use or installed in the future should receive similar hooding. The hoods on the Bipel machines were found to provide capture velocities ranging from 125 to 600 feet per minute. The ven tilation system serving these hoods should be balanced to provide a minimum capture velocity of 150 feet per minute at each hood. hm Attachments cc: W. F. Bavinger R. F. Bowers W. T. Diehl D. L. Eschelbach R. T. Gaskill T. J. Lang E. R. Lombard R. D. McIntosh, M. D. F. E. Repucci E. F. Ruiz, M. D. J. G. Shepherd N. A. Trombley L. P. Gendernalik Industrial Hygienist Table I Trenton Chemical Asbestos Dust Exposures November1972 Threshold Limit Value 1976 Proposed Threshold Limit Value Location Bay F-4, Breathing zone sample, //I Bipel operator Bay F-5, Breathing zone sample, #3 Bipel operator Bay F-5, Breathing zone sample, #4 Bipel operator Bay F-5, Breathing zone sample, Bipel press operator Bay F-5, Breathing zone sample, Bipel press operator Bay F-5, General area sample, between Bipel presses f/16 and #17 Bay F-7, Breathing zone sample, #2 Disc Pad Flat Grinder, operator Bay F-7, Breathing zone sample, #2 Disc pad Flat Grinder, inspector Bay F-7, General area sample, near #2 Disc Pad Flat Grinder Bay E-8, Breathing zone sample, Cenoer brake shoe assembly oven Bay E-8, Breathing zone sample, Brake shoe edge grinder Bay E-8, Breathing zone sample, Brake shoe outer radius grinder Bay E-8, Breathing zone sample. Brake shoe proof tester Asbestos Concentration fibers (> 5>M/ce 5,0 2.0 0.4 0.4 0.4 1.2 0.9 0.5 1.0 0.1 0.1 0.2 0.6 0.7 0.6 -2 Table 1 Trenton Chamical Asbestos Dust Exposures November 1972 _ Location Bay E-8, Threshold Limit Value 1976 Proposed Threshold Limit Value Breathing zone sample, Brake shoe packer Asbestos Concentration fibers 57^-^-----------2.0 0.1 Bay E-8, General area sample, near foreman's work table 0.0 Bay E-8, General area sample, south of outer radius grinder 0.1 Bay B-8, Breathing zone sample, #4 outer radius grinder loader 0.2 Bay B-8, Breathing zone sample, #4 outer radius grinder take-off man 0.1 Bay B-8, General area sample, between #4 and f/5 outer radius grinders 0.1 Bay D-3, Breathing zone sample, P-grade rolling machine operator 0.1 Bay D-3, Breathing zone sample, P-grade rolling machine operator 0.3 Bay D-3, Breathing zone sample, repeat of above, while #2 and #4 mixers are operating 0.6 Bay D-3, General area sample, north of P-grade rolling machine 0.1 Bay D-3, Repeat of above, while #2 mixer is operating 0.8 Bay D-3, Repeat of above, while ?/2 and 04 mixers are operating 0.1 Bay D-3, General area sample, near dust collector, during shake-down 1.3 Bay E-2, Breathing zone sample, batch weighman 0.3 3- Table 1 Trenton Chemical M*'g;.?r MTM" Threshold Limit Value 1976 Proposed Threshold Limit Value Asbestos Concentration fibers -(> 5>*)/cc___ 5.0 2,0 Bay E-2, Bay F-4, General area sample, between batch weighing stations Breathing zone sample, sweeper operator, operating Parke Vac-35 Breathing zone sample, batch weighman, while loading and unloading #4 mixer General area sample, on mixer mezzanine, while #4 mixer is operating Breathing zone sample, manufacturing manager, per forming normal plant tour General area sample, near manufacturing manager's office General area sample, near center of data proces sing room General area sample, south end of lunch room Breathing zone sample, dynamometer operator, while running destructive test on disc brake pads Breaching zone sample, garage mechanic brushing dust out of rear brake drums Breathing zone sample, garage mechanic blowing dust out of rear brake drums 0.1 1,0 4.3 0.1 0.0 0.0 0.0 0.1 1.0 0.2 0.0 Samples were obtained on cellulose ester, Type AA membrane filters, and analyzed by phase-contrast microscopy. Tabic 11 TrenCon Chemical v*a3&SigM9fVfy Location #1 Bipel. machine. loading point n Bipal machine, loading point Capture Velocity Feet oer Minute ----- TC------------- 300 #3 Bipel machine, loading point 125 04 Bipel machine. loading point 400 05 Bipel machine, loading point 600 #6 Bipel machine, loading point 300 #1 Disc pad flat grinder, at top of grinding wheel nil Bay E-8, edge grinder unsatisfactory Bay E-8, outer radius grinder satisfactory Bay B-8, 04 outer radius grinder 400-700 Bay D-3, P-grade rolling machine feed hopper side-draft hood 600-800 #4 mixer, unloading station 25-50 #4 mixer, loading hoist none Batch weigh stations satisfactory Velocity measurements were obtained with smoke tubes and an Alnor Jr. Velometer. Sliding longue / i * Belt width, inches up to 3 3 to 5 5 to 7 7 to 9 9 to U II to 13 Exhaust volume, cfm 220 300 390 500 6/0 740 Minimum duct velocity * 4500 fpm branch, 3500 fpm main. Entry loss * 0.65 velocity pressure for straight tohe-off 0.45 velocity pressure for topered tohe-off