Reference Material 8785: Air Particulate Matter on Filter Media

Abstract

Reference Material (RM) 8785 Air Particulate Matter on Filter Media is intended primarily for use in the evaluation of analytical methods used to characterize the carbon composition of atmospheric fine particulate matter (PM) for national air quality monitoring programs. This RM consists of a fine fraction (nominally < 2.5 μ m aerodynamic diameter) of standard reference material (SRM) 1649a Urban Dust resuspended in air and filtered onto quartz-fiber filters. RM 8785 will also provide the atmospheric-chemistry and ocean-sciences communities with a means to intercompare methods and laboratories for the measurement of elemental (black) carbon. RM 8785 has values assigned for total carbon, elemental carbon, and organic carbon mass fractions measured according to two thermal–optical methods: the Interagency Monitoring of Protected Visual Environments (IMPROVE) and Speciation Trends Network–National Institute of Occupational Safety and Health (STN–NIOSH) protocols. Each filter is uniquely identified by its air particulate matter (APM) number and its gravimetrically determined mass of fine SRM 1649a. We will discuss the method used to produce RM 8785 and the results of an intermethod and interlaboratory comparison that provided assigned values for the above analytes.