Document 938Gx2LOm1VyOqMnM3NJDe1g7

FILE NAME Brakes BRK DATE 1968 Apr 18 DOC BRK180 DOCUMENT DESCRIPTION Letter from Liberty Mutual Insurance Co. to Abex RE Inspection Results with Initial Inspection Report Attached ve we Hygiene Winchester - 2 Corporation American Brakeblok Division WINCHESTER WRCINIA 22601 TIL 703-662-1573 April 18 1962 Huckebra Hygienist Department Insurance Company Campbell Avenue Virginia 24005 Dear Mr. Huckebra In reference to your hygiene survey taken at our plant on January 23 and January 24 1956 for airborne lead and asbestos The followingfollowing are corrections and actions that have taken place SUBJECT Air Borne Dust Your samples number 5 7 and 3 rubber gasketing is being replaced on top area Also dust leaks down the sides near hoppers also of all hoppers the gates in the The area operator is to create a being instructed not to draft He is also being instructed to open the clam shell on the bottom of the mix buggy with caution not to open fully all at once to keep from creating creating as much dust as possibposilble e Also when opening the bags of asbestos asbestos he is to keep the bag bag below the intake duct so it it will receive as much dust as possible possible This duct is working to its maximum capacity This should be very effective for this area PLAINTIFF'S KAZ 002916- Huckebra The intake draft system in the functioning properly This will be the gasketing is installed Reppers 2 in each 1 is much more effective after Your sample number 11 This operation was observed by plant engineering and myself and we found the intake draft system working at its maximum capacity On our first observation of this they were dumping our most dusty mix All dust was being drawn up the intake draft even the dust escaping from between the lower boards in the mix buggy The day the survey was taken we feel the gates on the dust collector could have possibly been partially closed or the collector'not working at its maximum capacity . now is clear of cust The area Your samples number 12 and 13 The dust collector was found to be working at approximately of its its capacity It has been corrected We have installed in the rear of each preform a canvas curtain to contain escaping dust from getting away from the intake draft and keeping it out of the general room air This has worked very effectively On each preform scale we have installed an intake draft tube extending from the main collector to collect dust when the operator is weighing the mix This again will be very effective for the operators breathing zone and also the general area air SUBJECT Air Borne Lead Your sample nuncer 4 is answered under samples number 12 and 13 under Air Borne Dust paragraph two.. Your sample number 11 is answered under samples 6 number 7 and 8 under Air Borne Dust paragraphs and three KAZ KHALL02917 002917 gee rae se de AR tee CO ED S em tw eae . ie ae - rn ere Rann =~ - : aa OT A Xr George W. Huckebra April 15 3 Page Page 3 1968 eae -- -I .. i. Le Let We certainly feel corrections will be very effective in contati he vn arioi us opn erag tors breathing zanes and the general room air in the effected areas rw IZ Imay be of any assistance please feel free : : to Imay further , assistance assistance ' contact me mea de wha 6 oes . a a. . . Sh omnhe rene . . o ' ru woop) : ' Robert Brown , Personnel Manager Tet me Jr." , cer. C. H. Borcherding : ree , C. Blackwell Jr. M.D. D. Rennie . , .G Piley . Mallory Curtis nti . : of y. 2 s 7 oP t y aes - cor. Y yrarg? . , . , * . . 1 ad] aha es KHALL02918 002918 ABEX CORPORATION AMERICAN BRAKEBLOK DIVISION WINCHESTER VIRGINIA Hygiene Survey for Lead and Asbestos an 1s. wn a R . On January 23 and 24 1968 samples for airborne lead and as- bestos dust were collected in the wet and dry compounding areas in the book and the block press preforming areas and in the block and the strip finishing areas . The lead samples were analyzed our Hopkinton Laboratory and compared to a Threshold Limit Value of 0.2 Mg c.m of air . The dust samples were counted microscopically at 300X and com- pared to a Threshold Limit Value of 5 mppcf CONCLUSIONS 1 Asbestos in Air While some of the dust counts are above the recommended level of 5 mppcf for asbestos containing dust examination of the samples under the microscope indicate that only a few of the particles counted are actually fibers and the other appears to be dust other than asbestos Based on these observations I am not inclined to consider these levels as hazardous as suggested by the total count but to tamper this judgment in view of the fact that something less than 10 of the particles counted were actually fibers Reference to the data sheet will show that the grinding operations appear to be well controlled and the operations which resulted in the higher dust count were those which a large volume of air was displaced such as in the dumping operation and in the strip preform area LIBERTY MUTUAL INSURANCE COMPANY . KAZ KHALL02919 002919 2. Lead Concentrations in Air Reference to the data sheet will show only two were above the recommended Threshold Limit Value of 0.2 c.m of air One of these was general room air collected near press 8 in the strip preform area in view of the other levels in this area and our observations this is probably due to contamination of the filter paper somewhere in the sampling and packaging technique All other samples collected in this area were well below this level and those collected in the breathing zone of the operator were well within the suggested Threshold Limit Value The other high concentration of the airborne lead was collected in the breathing zone of the operator dumping the scale hopper on the wet compound line Our observation at the time was that a small plume of dust is released into the atmosphere when this operation is conducted Even considering the fact that this operation takes only a few minutes about 10-15 times per shift this is still high enough to constitute a significant exposure and additional controls are warranted 3 Exhaust Ventilation With the exception of the strip preforming and the dumping from the upper level to the lower level the exhaust ventilation equipment appears to be providing adequate controls These two exceptions are probably due to the operation itself creating turbulent velocities in excess of the control velocities designed for these installations and as a result dust is blown out of the influence of the exhausted environment Even though the dust concentrations in these areas are not considered severely hazardous they are high enough to warrant investi- of gation into the feasibility either providing better en- closures and increased velocities for these operations March 8 1968 GWH Dr. C. C. Blackwell Jr. Mr. Charles Borcherding Industrial W. Huakela Huakela Huakela Hygienist Loss Prevention Department Liberty Mutual Insurance Company LIBERTY MUTUAL INSURANCE COMPANY KHALL02920 KAZ C02920 INDUSTRIAL HYGIENE CORRECTIONS REQUIRED 1 Wet Compound Line - Mixer Exhaust It is recommended that all the mixers on the wet compound line be provided with an inward draft sufficient to control the puffs of dust which are released when dumping the weighing hopper 2 Strip Press Preformin angd Dumping Locations on First Floor It is recommended that the exhaust ventilation on these locations be improved either by increased velocity or in- proved enclosure to a degree sufficient to control the puffs of dust emitted when operating the presses and dumping the material from the upper level to the lower level KAZ KHALL02921 002921 DISCUSSION On the days of the survey all operations appear to be operating normally and for the part the exhaust ventilating equipment doing job for appeared to be the | which it was intended 1 As was mentioned earlier some of the dust concentrations are above the Threshold Limit Value of 5 mppcf suggested for dust containing asbestos However since something less than 10 1 of the particles counted were fibers it is felt that the severity of the situation is not quite as serious as would be the case if all the particles were fibers MANAGEMENT INTEREST The interest of management and supervision in providing a healthful environment seems to be carrying over well to the individual employees During our survey we noted no evidence of ventilation equipment abuse or lack of respect on the part of the individual employees Since the exhausting of air contaminants for this plant is such an important part of the operation it is urged that continued emphasis be placed on quality maintenance and proper utilization of equipment provided KAZ KHALL02922 KHALL02922 002922 DATA Method of Collection AIR BORNE DUST ___. Collected in distilled water with midget impingers at the rate of 5 m Method of Analysis , Counted with microscope at 300X using a Spencer Hemacytometer Counting Chamber Recommended Threshold Limit Value for dust containing asbestos _ 5 million particles per c ft of air mppef SAMPLE # 1 2 4 5 6 7 8 LOCATION RESULTS IN MPPCF Breathing zone of the operator on automatic block chamfer grinder 810 - Note The exhaust installation on the grinder appears to have a good inward draft though enclosure might be improved to reduce amount of - flying material 1.9 Same location 2.3 Operator's breathing zone - rough grinder 806 Breathing zone of the operato-r automatic block chamfer 654 2.6 4.0 Operator's breathing zone - disc finishing operation 22 - machine 1209 ~ Note The exhaust appears to be doing a very good job of dust control at this operation General room air in scale area weighing material for wet mix line Little dust is apparent in the area ' Operator's breathing zone general room air during the weighing of asbestos and emptying of the hopper for the wet line 3.5 7.8 7.9 Operating breathing zone weighing asbestos and dumping for the wet line . 6.0 KAZ KHALL02923 002923 Data continued Dry line weighing general room air before weighing sabestos No dust apparent in the area 10 Operator's breathing zone weighing asbestos for dry line only no other operations included in this sample 11 General room air on the ground level where the mills are dumped into the cart Some dust noted to be escaping from the enclosure during the filling of the cart Operator's breathing zone in the strip preform area Some dust seemed to be coming out of the mole when the plate is placed on top of the filling Most of the dust appears to be the tap which is dusted on the moles 13 General room in the strip preform area 0.2 4.8 8.3 12.9 10.6 KAZ KHALL02924 002924 DATA AIR BORNE LEAD Method of Collection filter Collected on pump paper using vac~-nm Method of Analysis Dithizone method read on Beckman spectro- photometer Threshold Limit Value for air borne lead 0.2 Mg./c m SAMPLE # 1 -2 3 4 LOCATION RESULTS MgPb Operator's breathing zone strip preform area mix 353 .01 Strip preform area press 5 operator's breathing zone mix 154 .01 General room air in back of press 6 in the strip preform area General room air back of press 8 in the strip preform area . .14 .21 General room air wet line compounding .12 Operator's breathing zone block grinding automatic bur and chamfer grinder General room air near dust collector room in block grinding area .02 Operator's breathing zone in dry mix dump area on ground level - dumping mix at the time of sample General room air in dry mix dump area during dumping .10 .09 Operator's breathing zone with wet line compound weighing operation .04 Operator's breathing zone during the dumping of the weighing hopper on the wet line - Note There is no screen on this mixer and a small puff of dust is noted to be generated when first starting to empty the weighing hopper 4.02 KAZ KHALL02925 002925