THE DEVELOPMENT OF AN IMPROVED METHOD FOR THE DETERMINATION OF COAL-TAR PITCH VOLATILES (CTPV) IN AIR

Test samples were collected at a range of sites using the MDHS 68 samp ler, a 7-hole sampler, and a cyclone respirable-dust sampler. Glass fi bre, Zefluor, Fluoropore and silver (0.8 and 5 mu m) filters mere comp ared for weighing error, handling characteristics, and amount collecte d. The effects of a carbon back-up, of extraction solvent, and of anal ytical method were studied. The current HSE method for the sampling an d analysis of coal tar pitch volatiles, MDHS 68 has been reviewed. It is recommended that the MDHS 68 sampler be replaced by a 7-hole head c ontaining a silver or PTFE filter (similar to 1 mu m pore size), with a graphitised carbon back-up if efficient collection of 2 to 4-ring PA Hs is required. Cyclohexane is recommended as the extraction solvent. Methods of analysis which quantify the fume as a whole (MDHS 68, u,v., ELSD) were shown to give a response which varied according to the typ e of CTPV generating process. Therefore analysis of specific PAHs of o ccupational interest, by CC-MS or HPLC is recommended. Crown copyright (C) 1998 Published by Elsevier Science Ltd.