ATMOSPHERIC AEROSOL SAMPLING BY AN ANNULAR DENUDER SYSTEM AND A HIGH-VOLUME PM(10) SAMPLER

An Annular Denuder System (ADS) was used to study sampling errors of t otal PM(10) and soluble ionic species concentrations determined by the high volume PM(10) (HVPM(10)) sampler. Experimental results show that in the HVPM(10) sampler, more alkaline glass fiber filters collect mo re sulfate and nitrate but less ammonium ion than quartz filters. Howe ver, total PM(10) concentrations do not seem to depend on the types of filters. Artifact sulfate concentrations in glass fiber filters of th e HVPM(10) sampler are found to exceed those predicted by the Coutant' s model. It is suggested that artifact sulfate and nitrate not only oc cur within filters but also in particle deposits. Chloride ion concent rations in the filters of the HVPM(10) sampler are underestimated sign ificantly due to evaporative loss of ammonium chloride.