A strategy for coal mine respirable dust sampling using multi-stage impactors for characterization purposes.
Engineering Health and Safety in Coal Mining. Proceedings of the Society of Mining Engineers Symposium, March 2-6, 1986, New Orleans, Louisiana, A. W. Khair, Editor; pages 202-215, 9 references
A procedure was developed for obtaining samples of respirable dust from coal mines using multistage impactors capable of classifying the dust according to its aerodynamic diameter, for subsequent characterization. The procedure involved the use of the Sierra Model 298 Marple personal cascade impactor provided with a microbalance having a precision of 1 microgram. The equipment was tested in an aerosol test chamber to determine impactor collection efficiency and sampling time. Experimental results revealed that optimal sampling time for dust concentrations of about 1mg/m3 was 4 hours, as compared to 45 minutes for dust concentrations of 4mg/m3. Field studies carried out at several mines revealed that slightly different operating procedures were required for each individual mine. Hoods were placed around the inlet port of the impactor without increasing the resistance to airflow, to protect the instrument from being hit by water sprayed by the miners. The authors conclude that multistage impactors provide better aerosol size data than single stage samplers, in addition to classifying the samples according to aerodynamic diameter.
Mining-industry; Dust-sampling; Sampling-methods; Air-quality-control; Dust-analysis; Dust-control; Exposure-limits; Occupational-exposure; Sampling-equipment
Paper in Engineering Health and Safety in Coal Mining.