Artifacts of ionic species for hi-vol PM10 and PM10 dichotomous samplers

This study employs two Annular Denuder Systems (ADS10 and ADS2.5) to quantify sampling artifacts of soluble ionic species determined by the high-volume PM10 (hi-vol PM10) sampler using quartz fiber filters and PM10 dichotomous (Dichot) sampler using Teflon filters. According to the experimental results, the percentage of artifact of a species over the actual species concentrationis +11, +8 and +15% for PMHV10, PMDICH10, PMDICH2.5, respectively, for sulfate species; −16, −21 and −21% for PMHV10, PMDICH10, PMDICH2.5, respectively, for nitrate species; −24, −32 and −54% for PMHV10, PMDICH10, PMDICH2.5, respectively, for chloride ion species; −17, −21 and −18% for PMHV10, PMDICH10, PMDICH2.5, respectively, for ammonium ion species. For volatile species such as nitrate, ammonium and chloride ions, additional sampling losses due to gas–particle and particle–particle interactions are more important than pure volatilization loss. Amount of positive and negative artifacts is approximately equal and the amount of net artifact does not account for more than 15% of PM10 concentration.