Environmental surveys in the European man-made mineral fiber production industry.

This paper presents estimates of airborne fiber concentrations and fiber size for European man-made mineral fiber (MMMF) factories on the basis of measurements made in 1977—1980. The airborne fiber concentrations previously reported at a conference of the World Health Organization (WHO) and the International Agency for Research on Cancer in 1982 have been revised to harmonize the results with the WHOEuropean MMMF reference counting level. The result was an approximate doubling of the reported airborne fiber levels. After the revisions the average combined occupational group concentrations in the rockand glass-wool plants were still generally low (<0.1 fibers/ml). In the glass continuous-filament factories the airborne fiber concentrations were very low (< 0.01 fibers/ml). The average plant median for fiber length ranged from 10 to 20 µm, and the corresponding median diameters ranged from 0.7 to 20 µm. In general the glass-wool fibers were thinner than the rock-wool fibers. The fiber concentrations measured in other studies in the MMMF production and user industries are reviewed. Higher levels (between 0.1 and 1.0 fibers/ml) have been measured in some insulation wool production, secondary production, and user industries. The highest levels (> 1.0 fibers/ml) occurred in very fine glass-fiber production and in other specialist insulation wool usage.