Size-selective Samplers for Estimating “Respirable” Dust Concentrations

The Health and Safety Laboratory (HASL) of the U.S. Atomic Energy Commission has developed and used a family of size-selective air samplers for field survey work. Each sampler operates at a flow-rate suitable to a particular suction source used by HASL. They all consist of a cyclone collector followed by an efficient filter, and range in capacity from 0.9 l./min to 40 ft3/min. The collection characteristics of the cyclones were selected so that the fraction of the sample collected on the filter would be equivalent to the material which would penetrate to the non-ciliated portions of the lung. The standard of comparison for collection efficiency is based upon human retention experiments performed by BROWN and co-workers, LANDAHL and co-workers, and others. Representative field data are presented illustrating the relative proportions of “respirable” and “non-respirable” dusts at various operations in the uranium and beryllium industries.