Document KyD2Qg5Y1jp6jdxRdGMzoDvo

36 Proc. roy. Soc. Med. Volume 70 January 1977 Table3 PefiCfil sir s*m>MIc tad truck krskt r*glr Automobile brake repair Blowing dust from brake drums: Distance 1-1.5 m Distance 1.5-3 m Distance 3-6 m Background (5 min after air jet blowing, distance 3.6- 16 mi Background (7-14 mm after air jet blowing, distance 19.6-22.6 mi Peak fibre concentration So. of [fibres per mf) samples Mean Ronge J IS.O *3 3.3 1.6 2 o.: % 0.1 6.6-29.4 2.B-4.2 0.3-4.8 0.1-0.2 0.1 13 Truck broke repair Renewing used linings by grinding (distance 1-1.5 m) Background to grinding used linings: Distance 3.3 m Distance 8.3 m Distance 20.0 m Bevelling new linings Background to bevelling new linings: Distance 2.4 m Distance 3.6 m Distance 9.] m 10 > T 4 1 * I 4.8 I.J 0.8 37.3 0.4 1.7-7.0 1.2-1.7 0.6-1.0 0.2 23.7-72.0 0.6 0.3-0.5 0.3 23 away from the operator. From six to ten other mechanics work within an area up to 20 m from this operation are exposed to asbestos as well. Since a person breathes about one cubic metre of air an hour, multiplication of the fibre con centrations by one million gives the number of fibres inhaled during this period. Fibre con centrations measured during bevelling of truck linings were as high 8S 72 f/ml and averaged about 37 f/ml. Background counts were measured up to 9.1 m away from this operation (0.3 f/'ml'). Fibre concentrations measured during drilling holes for rivets and grinding ranged from 0.3 to 29.2 f,'ml. as reported by Boillat & Lob (1973). Four of the nine values exceeded 5 f/ml. Conclusions The existence of significant exposure during brake servicing operations necessitates the following measures: ledge support under a grant from the National Institute of Environmental Health Sciences. ES 00928 and support bv the Ford MotorTjctmpanv. MSW wishes to acknowledge support unde: a post-doctoral fellowship from the N1EHS. ES 02565. We are grateful to the following for assistance ir. obtaining brake dust samples: Professor Donald Bowes. University of Glasgow. Scotland; Mr L B Bowes. Department of Labour and Industry. Adel aide. Squth_Australia: Dr Trevor Turner. Adel aide. Sputh_Australia; Professor Jean Bignon. Hospital Laennec. pads^France: Maunu Harme. Geological Survey of Finland. Otanienti. Finland: Dr G. Gaal. Helsinki University of Technology. Helsinki. Einlaod; Dr K. Robock and Dr W Klosterkotter, Institut fur Hygiene und Arbcitsnte- dizin des Klinikum der Universttat Essen. West Germany. (I) Implementation of industrial hygiene proced.ur.esjo control exposure. (2^ Clinical studieS~~Of garage mechanics to de termine evidence of asbestos-related disease. i.3> Epidemiological studies of the mortality experience of exposed workers. In addition, the entire variety of dusts and other materials present in brake repair work should be characterized in order to determine its disease potential, especially silica and lead compounds. Acknowledgment: The authors wish to acknow REFERENCES Bayer S C. Browo T A St 2.umakk R D (197$) Document TR-&4. t'S Public Health Service. Cincinnati. Ohio Boillat M A it Lob M (19*3) medizinische Wochenschnit 103. 39 Bouhuya A {19*5) Annuls of Internal Medicine 83. 898 Harwell J T 11957) H ear J. 119 CirTolt W C i m:)BruLtbPlauics 3S.-H4 Cattleman B. Camarota L A. Frilaeh A J. Mauocchi S 4 Crawley ft C 119*5) Public Health Reports 90. 254 Darn J M J (1965) Annols oj the Sew York Academy ofSciences 132. 98 6001 0019 pprvrvt tpT?n Ttv prvpri