Precision of PM Measurements with the UNC Passive Aerosol Sampler

The UNC passive aerosol sampler measures mass concentrations and size distributions of indoor, outdoor, and occupational particulate matter. This study assessed the precision of passive sampler measurements using data from duplicate pairs of samplers that were deployed in a large field study. Particle count and size data were used to calculate PM[25] and PM[10] concentrations. To determine precision, the concentrations measured by duplicate samplers were compared to one another. Results showed that this sampler provides mass concentrations of PM[25] and PM[10] in the field with relative standard deviations that approach about 15%, with greater precision associated with higher concentrations. Variability between measurements was associated with counting statistics and with differences in the open area of the passive sampler mesh screen.Master of Science in Environmental Engineerin