|Document ID (ISN)||69689|
|ISSN - Serial title
||0047-1879 - Japanese Journal of Industrial Health - Sangyō-Igaku
|Convention or series no.
||Kumagai S., et al.
||Estimation of asbestos exposure among workers repairing asbestos cement pipes used for conduits
||Sekimen semento kan (suidōkan) no shūyen sagyō ni tomonau sekimen bakuro [in Japanese]|
||May 1993, Vol.35, No.3, p.178-187. Illus. 40 ref.
||Asbestos cement pipes (ACPs) account for 16.2% of all conduits in Japan, although their production was suspended in 1985. When such a conduit is damaged, workers cut off the damaged conduit using a high-speed disk cutter and replace it with a new conduit. This operation develops a cloud of asbestos-containing dust. To establish typical working conditions, an experienced worker cut an ACP in a hole dug in the ground. Dust was sampled at several points both inside and outside the hole. A self-administered questionnaire survey was then conducted among 1,048 men doing conduit repair work. The concentration of asbestos fibres >5Ám with 3:1 aspect ratio ranged from 48 to 170 fibres/mL (92 fibres/mL on average) inside and 1.7 to 15 fibres/mL outside the hole. The concentration inside the hole exceeded the ceiling limit (10 fibres/mL) recommended in Japan. A concentration of 92 fibres/mL is equivalent to 0.96 fibres/mL as an 8-h TWA. The number of subjects with experience of cutting ACPs was 849, and their average length of service was 14.2yr. The time spent cutting ACPs was estimated to average 17 d/yr. Only 18.1% of the subjects used respiratory protection. If these workers worked 17 d/yr in cutting ACPs for 14yr and were exposed to 1 fibre/mL of asbestos per day, the life-time excess mortality rate of both lung cancer and mesothelioma could be as high as 30/100,000 (OSHA model).
||Japan; asbestos; water and sanitation services; exposure evaluation; repair work
||abrasive-wheel cutting-off machines; conditions of exposure
||D - Periodical articles
|Country / State or Province||Japan|
||Dust, aerosols and related diseases
|Broad subject area(s)
||Water and sanitation services