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MONITORING AND LABORATORY DIVISION
STANDARD OPERATING PROCEDURE

S.O.P. No. MLD 029 - Analyzing the Mass of Dichotomous PM10 Filters

SCOPE

This document describes the methodology used by MLD staff to analyze the mass of Dichotomous PM10 filter samples.

SUMMARY OF METHOD

Individual teflon filters (37 mm diameter) are weighed on an electronic microbalance before and after field sampling.  A sample consists of a filter set, a coarse filter onto which 2.5 to 10 um particles are deposited, and a fine filter that collects particles less than 2.5 um.  Filter weights are recorded directly employing a microbalance-computer interface which then calculates the mass of particles per cubic meter of air (ug/m3).