A Field Study of Three Collocated Ambient PM₁₀ Samplers

The performances of three ambient PM₁₀ samplers were studied at three monitoring stations in Taiwan. It was found that differences in the daily measured PM₁₀ concentrations of the SA 1200 and Wedding high‐volume samplers are now within ± 10% since the former now has a closer cut‐point to the latter than in the earlier SA 321 A model. The Wedding beta gauge automatic sampler was found to be applieable in rainy and humid weather conditions in Taiwan. Its daily PM₁₀ concentrations are typically within ± 10% of those of the Wedding highvolume sampler. The particle loading effect of Wedding highvolume and beta gauge samplers was found to be important. To avoid sampling errors due to the loading effect with ambient PM₁₀ samplers, they must be cleaned regularly at an interval depending on the ambient particulate level.