Condensible Particulate Matter: Regulatory History and Proposed State Agency Policy

摘要

Pariculate matter is the most widely regulated air pollutant emitted from industrial sources. Health concerns regarding paniculate matter concentrate on 'fine' particulate matter - particulate matter less than 2.5 microns (PM2.5). Particulate matter exists in the solid and liquid physical states, and gases or vapors may also condense to form particulate matter. The latter, condensible particulate matter, is of great concern due to the inherently small size of condensation products; overwhelmingly, condensible paniculate can be classified as PM2.5. Test methods are often utilized in order to prove compliance with specified limits. The data generated from the test methods may only be used for specific purposes dependant on the parameters of the sampling systems. Therefore, data generated from a test method may be applicable to a compliance demonstration for an empirically derived emission limit. However, a more encompassing methodology may be necessary in order to better evaluate the absolute emissions of a pollutant. Particulate matter may be measured using the EPA Method 5 sampling train and measuring filterable particulate matter (front half catch). This data is the only requirement for particulate matter in most New Source Performance Standards. However, measuring the condensible particulate matter (back half catch) and summing the filterable and condensible will better approximate the contribution to ambient loading from the emissions of primary particulate matter.