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Document ID (ISN)78517
CIS number 02-837
ISSN - Serial title 1076-2752 - Journal of Occupational and Environmental Medicine
Year 2001
Convention or series no.
Author(s) Graham W.G.B., Vacek P.M., Morgan W.K.C., Muir D.C.F., Sisco-Cheng B.
Title Radiographic abnormalities in long-tenure Vermont granite workers and the permissible exposure limit for crystalline silica
Bibliographic information Apr. 2001, Vol.43, No.4, p.412-417. 15 ref.
Internet access 02-0837.pdf [in English]
Abstract To study the prevalence of radiographic abnormalities among retired granite workers, 408 x-ray films were examined. Dust exposures were estimated for workers hired after 1940, when the dust-control standard of 10 million particles per cubic foot (equivalent to 0.1mg/m3) was put in place. Dust levels were gradually reduced from 1940 to 1954, after which average quartz exposures stabilized to average approximately 0.05 to 0.06mg/m3; however, about 10% to 15% of samples after 1954 exceeded 0.1mg/m3. Of the 408 x-ray films, 58 were taken on workers hired before 1940, and 25.9% showed abnormalities. 350 x-ray films were taken on workers hired in 1940 or after, and the prevalence in this group was 5.7%. The radiographic changes in workers hired after 1940 are likely to be due to excessive exposures during the first 15 years of dust control. It is concluded that if the exposure standard of 0.1mg/m3 is rigorously observed in the workplace, radiographic abnormalities caused by quartz dust in long-term workers will be rare.
Descriptors (primary) threshold limit values; silica; radiological changes; mining industry; respirable dust
Descriptors (secondary) granite; chest radiography; frequency rates; exposure evaluation
Document type D - Periodical articles
Country / State or ProvinceCanada; USA
Subject(s) Mines and quarries
Broad subject area(s) Chemical safety
Browse category(ies) Occupational exposure limits
Mining and quarrying