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Document ID (ISN)69689
CIS number 97-1564
ISSN - Serial title 0047-1879 - Japanese Journal of Industrial Health - Sangyō-Igaku
Year 1993
Convention or series no.
Author(s) Kumagai S., et al.
Title Estimation of asbestos exposure among workers repairing asbestos cement pipes used for conduits
Original title Sekimen semento kan (suidōkan) no shūyen sagyō ni tomonau sekimen bakuro [in Japanese]
Bibliographic information May 1993, Vol.35, No.3, p.178-187. Illus. 40 ref.
Abstract 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).
Descriptors (primary) Japan; asbestos; water and sanitation services; exposure evaluation; repair work
Descriptors (secondary) abrasive-wheel cutting-off machines; conditions of exposure
Document type D - Periodical articles
Country / State or ProvinceJapan
Subject(s) Dust, aerosols and related diseases
Broad subject area(s) Chemical safety
Browse category(ies) Water and sanitation services
Exposure evaluation