[Calibration of selective samplers for respirable dust]

The AA., after a short introduction on the concepts of respirable dust consider the double stage selective samplers in the literature. They suggest three of them, which are all characterized by different suction flows; the features of separation of the dust in the air are documented by means of calibrated mixtures of aerosol. As to the penetration ACGIH curve, satisfactory results are obtainable fro the 12 mm sampler with a 10 l/min flow and for the 25.4 mm sampler with a 70 l/min flow. The tests achieved with the Dorr-Oliver 10 mm metal sampler do not agree with the above mentioned curve for a capacity included between 0.7 and 2.5 l/min.