A PERSONAL DIFFUSION SAMPLER FOR EVALUATING TIME WEIGHTED EXPOSURE TO GASEOUS HYDROGEN SULFIDE

Abstract

A simple badge type diffusion tube, 35 mm photo film plastic case, was used for evaluating time-weighted exposure to H₂S using reagent impregnated filters (Whatman No.1). The black shade of the reagent filter, 10% Pb(OAc)₂ and 2% AgNO₃ under the concentration of H₂S below 20 ppm for 2 to 4 hours agreed inversely to the diffusion length of the tube, and lineally well correlated with dose-time unit (C×T) and the theoretical value of diffusion. The device was proved to be capable of being used in realistic working conditions provided that there is no extreme fluctuations of H₂S.