Adequacy of a single monitoring site for defining mean outdoor concentrations of fine particles in a demarcated residential community.

Abstract

Fine and coarse inhalable particle data for 60 days from five demarcated communities in U.S. cities, each with three monitoring sites, were examined to test whether the mean particle mass concentrations measured at the three sites are equivalent within each community. The result of this kind of analysis should be useful in determining how many sites in a community are adequate to provide a reliable measure of the outdoor component of an exposure estimate in that community. Only fine particles (D < 2.5 μm, aerodynamic diameter) were found to have equivalent mean concentrations, suggesting that only one monitoring site in each community is required to provide an adequate exposure estimate of the outdoor component. However, variable concentrations of total inhalable and/or coarse (2.5 μm< D < 15 μm) particles were found, which Implies a requirement for multiple monitoring sites.