AAAR 32nd Annual Conference
September 30 - October 4, 2013
Oregon Convention Center
Portland, Oregon, USA
Abstract View
Application of an Eight-Channel Optical Particle Counter to Continuous, Long-term PM2.5 Monitoring
ODELLE HADLEY, Mark Moore, Olympic Region Clean Air Agency
Abstract Number: 133 Working Group: Instrumentation and Methods
Abstract When air-operating permits were issued for two biomass cogeneration plants, one in Port Angeles and the other in Port Townsend, citizens in the region expressed concern and attempted to halt progress on these permits through appeals and community protests. Chief among their concerns was that current ambient air quality monitors were inappropriately sited to properly assess regional air quality and the potential emissions increase from these facilities. In response, the Olympic Region Clean Air Agency (ORCAA) implemented a study measuring the neighborhood scale variability of ambient PM2.5 concentration throughout the Olympic Peninsula. The data will be used to determine the most representative location for long-term ambient air quality monitors in each county. ORCAA currently uses Radiance Research M903 nephelometers to obtain real-time air quality data throughout the region. The study incorporates four, MetOne 212-2 optical particle counters (OPC) into ORCAA’s existing air monitoring network. The OPCs produce size resolved, atmospheric particle number concentrations ranging from 0.3 to 10 microns. The OPC data are evaluated against the Radiance Research M903 and the EcoTech Aurora 1000 nephelometer, as well as a tapered-element oscillating microbalance (TEOM), configured to meet the PM2.5 federal equivalence method (FEM) criteria. Results from these side-by-side comparisons, as well as preliminary field measurements, are presented. The OPC, hourly-averaged particle number concentrations correlate well (R2 > 0.9) with both nephelometers and the TEOM, however the strength of the correlation and the linear relationship depend on the aerosol sizes selected and the location and season in which the measurements are made.