Effect of Positive Artifact on the Measurement of Fine Particulate Carbonaceous Substances

Abstract

This paper describes the gaseous organic carbon (OC) concentration in the PM_2.5 and positive artifact. The observations were done from April 2014 to March 2015 in Komae, Tokyo. In order to understand the influence of the gaseous OC, the measuring devices equipped with a denuder (denuder-filter method) and without a denuder (filter method) were simultaneously operated in parallel. The samples were analyzed for the OC concentrations by a thermal optical reflectance (TOR) method using a carbon analyzer manufactured by Sunset Laboratory. The average organic carbon concentrations were 2.8 μgC/m³ (filter method) and 1.7 μgC/m³ (denuder-filter method). The mean gaseous OC concentration was estimated to be 1.1 μgC/m³. It turned out that about 39% was the gaseous OC among the OC concentrations in the PM_2.5.