THE INDOOR, FINE PARTICULATE ORGANIC CARBON MEASUREMENT ARTIFACT IN SEATTLE

摘要

The objective of this work was to compare indoor and outdoor concentrations of fine particulate organic carbon (OC) and elemental carbon (EC), determined from undenudcd quartz filters. PM_(2.5) samples were collected in Seattle at a central site and indoors and outdoors at private residences between February 22 and May 25, 2000, and analyzed for OC and EC content. Indoor and outdoor denuded quartz filters were also analyzed for OC and EC, Indoor OC sampled onto undenuded quartz filters was typically higher than outdoor OC, while outdoor EC was higher than indoor EC. For denuded quartz filters, the indoor OC was not typically higher than the outdoor OC. Indoor OC mass collected on an undenuded quartz fiber filter frequently exceeded the PM_(2.5) mass collected on a Teflon filter. This anomaly results from a positive sampling artifact from the adsorption of semi-volatile organic components from the vapor phase onto quartz filters.