ABSTRACT

Gravimetric measurement of particulate matter (PM) concentrations in ambient environments is the basis for regulation of PM fractions (i.e. PM₁₀ and PM_2.5) under the Federal Clean Air Act. While the measurement is straight forward, inherent elements of uncertainty enter the analysis, resulting in much larger uncertainty in the concentration calculation. This paper discusses the importance of uncertainty approximation and analyzes the uncertainty inherent in a gravimetric PM concentration measurement. Utilizing a first order Taylor Series approximation and analytical derivatives, the overall system uncertainty is computed. Additionally, this paper uses a sensitivity analysis of the contributing uncertainty elements in order to identify the most critical measurements and their implications on the calibration, operation, and design of PM samplers.