The filtration efficiency of organic vapor sampling tubes against particulates.

The particulate filtration efficiency of industrial organic vapor sampler tubes is of interest for air sampling in work environments containing toxic materials as both vapor and particulate, or where inert particles contain adsorbed toxic material. Particulate collection efficiencies, measured with dioctylphthalate and polystyrene latex aerosols ranged from 70-90%. However, only 20% of this total is deposited on the active sorbent (charcoal granules). Considerable variability in collection efficiency between tubes was observed. Recommendations are made for obtaining improved contaminant estimates using these tubes.