A Pilot Study: The UNC Passive Aerosol Sampler in a Working Environment

OBJECTIVES: Dust is generally sampled on a filter using air pumps, but passive sampling could be a cost-effective alternative. One promising passive sampler is the University of North Carolina passive aerosol sampler (UNC sampler). The aim of this study is to characterize and compare the UNC sampler’s performance with PM(10) and PM(2.5) impactors in a working environment. METHODS: Area sampling was carried out at different mining locations using UNC samplers in parallel with PM(2.5) and PM(10) impactors. Two different collection surfaces, polycarbonate (PC) and carbon tabs (CT), were employed for the UNC sampling. Sampling was carried out for 4–25 hours. RESULTS: The UNC samplers underestimated the concentrations compared to PM(10) and PM(2.5) impactor data. At the location with the highest aerosol concentration, the time-averaged mean of PC showed 24% and CT 35% of the impactor result for PM(2.5). For PM(10), it was 39% with PC and 58% with CT. Sample blank values differed between PC and CT. For PM(2.5), PC blank values were ~7 times higher than those of CT, but only 1.8 times higher for PM(10). The blank variations were larger for PC than for CT. CONCLUSIONS: Particle mass concentrations appear to be underestimated by the UNC sampler compared to impactors, more so for PM(2.5) than for PM(10). CT may be preferred as a collection surface because the blank values were lower and less variable than for PC. Future validations in the working environment should include respirable dust sampling.