Differential Pressure as a Means of Estimating Respirable Dust Mass on Collection Filters

Abstract

Abstract Researchers have studied various types of respirable dust sampling filters to determine if the differential pressure across them at a constant air flow rate can be used to estimate the accumulated dust mass. Results suggest that glass fiber depth filters that allow the dust particles to penetrate well into the filter material have considerable merit. The correlation between the increase in differential pressure (AP) and dust mass (M) when using 37-mm glass fiber filters is linear, provided they are not loaded with more than approximately 5 mg of dust. Under these conditions, the relationship between differential pressure and dust mass can be described by the equation [°P(cm H2O) = 0.25 M(mg)]. Most of the data fall within ± 25 percent of a best-fit regression line and have a correlation coefficient (R2) of 0.88. These results were obtained using coal dusts from Pittsburgh, Upper Freeport, and Pocahontas seams mixed with various percentages (0 to 100%) of rock dust. The density of these dusts vari...