Performance of Passive Samplers Analyzed by Computer-Controlled Scanning Electron Microscopy to Measure PM10–2.5

We report on the precision and accuracy of measuring PM10–2.5 and its components with particles collected by passive aerosol samplers and analyzed by computer-controlled scanning electron microscopy with energy dispersive X-ray spectroscopy. Passive samplers were deployed for week-long intervals in triplicate and colocated with a federal reference method sampler at three sites and for 5 weeks in summer 2009 and 5 weeks in winter 2010 in Cleveland, OH. The limit of detection of the passive method for PM10–2.5 determined from blank analysis was 2.8 μg m–3. Overall precision expressed as root-mean-square coefficient of variation (CVRMS) improved with increasing concentrations (37% for all samples, n = 30; 19% for PM10–2.5 > 10 μg m–3, n = 9; and 10% for PM10–2.5 > 15 μg m–3, n = 4). The linear regression of PM10–2.5 measured passively on that measured with the reference sampler exhibited an intercept not statistically different than zero (p = 0.46) and a slope not statistically different from unity (p = 0.92...