Document aB8mGK1BZGaE7M6a73Q9YOKq9

t - i' S' `Vf V 212 WILLIAM V LORIMER ET AL TABLE IV Personal Samples--Truck Brake Service Operation Concentration (ftbers/ml) Beveling new linings Beveling new linings Beveling new linings Beveling new linings Beveling new linings 31 7 237 32 7 72 0 263 Background Samples--Truck Brake Seruice Operation Distance Background to beveling linings Background to beveling linings Background lo beveling linings Background to beveling linings Sft ' 12 ft 12 ft 30 ft Concentration (fiben/ml) 06 05 03 03 TABLE V Automobile Broke Lining Service Operation Comparison of Optical and E M Fiber Counts Optical Microscopy Electron Microscopy Light grinding of new linings before installation Grinding new Immgs before installation Blowing dn<it ofT drum with air jet Cleaning brake drum with hand brush Background to blowing out brake drum (10 feet away) Bar kgrourid to blowing out brake drum (20 feet away) ( background to blowing out brake drum (65 feet away) iftben/ml) 4.8 27 04 36 03 08 1 fig/m' 530 660 11 65 02 01 02 x ray, and pulmonary studies Three men were-excluded from analysis because they had worked m a shop for less than 10 years Also excluded from analysis were nine men whose occupational history raised the possibility of other asbestos exposure Two men'Were excluded because of known1 chest disease The remaining 90 believed themselves to fee healthy{ all either were currently working (84) or'had retired because of age (6), ! << r- Occupational Categories ; -, ! General mechanics ' 67 ' '* Body workers'- " 7 *. Undercoaters 5 ,,1 Lubrication^ ^ i 4 Phinters^- - ,, *v - 2 /- A Miscellaneous other crafts' r*'- -_5 90" s ) ^* iV -rf '"'S w. :r1 w f-r i/'