Comparative Measurements with Various Instruments: Problems in the Evaluation of Dust Exposures in the Hard Coal Mining Industry.
NIOSH 1990 Sep:625-635
A review was provided of the development of instrumentation used to measure dust exposures in the hard coal mining industry. The tyndalloscope was used for dust exposure monitoring in the mining industry from the middle of the 1950s through 1973. Problems associated with this equipment were the dependence of scattering light intensity, not only on concentration but also on particle size. The MPG-II equipped with a horizontal elutriator was used in the Federal Republic of Germany to measure maximum workplace concentrations. The TBF-50, a double cyclone instrument was used in routine measurements as well. The dependence of cyclone efficiencies on suspended dust uptake was a problem which was also encountered in personal dust samplers such as the Simpeds 70-MK-II. Other items considered in this review were the conversion factors for TBF-50 with and without filters, conversion factors for Simpeds and MPG-II, ash proportion obtained by MPG-II in mass percent, the arrangement of dust measuring instruments in comparative measurements, conversion relation for different faces at low concentrations, and the relation between gravimetric and tyndallometric intensity values of respirable dust concentrations.
Analytical-methods; Air-sampling-equipment; Work-environment; Airborne-particles; Dust-sampling; Analytical-instruments; Analytical-processes; Air-quality-monitoring; Air-samplers; Dust-samplers;
DHHS (NIOSH) Publication No. 90-108
Proceedings of the VIIth International Pneumoconioses Conference