AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Performance Evaluation of Three Co-Located Ultrafine Particle Monitors Near the 710 in California
Ahmed Mehadi, Donald Hammond, Jeff Wright, Andrea Polidori, Timothy Morphy, ROBERT ANDERSON, CARB Monitoring and Laboratory Division
Abstract Number: 363 Working Group: Source Apportionment
Abstract Ultrafine particles (UFP) are important indicators of many nearby pollution sources, including combustion sources, motor vehicle traffic, and others. New regulations and health studies have increased the importance of accurate and widespread measurements of these particles. Specifically, while methods for measurement of UFP are well-established, the instrumentation is often complex and not suitable for routine measurement without significant time commitment from a skilled technician or scientist.
This study evaluated the durability and precision of the upgraded TSI CPC Model 3783 or the same instrument labeled as the Teledyne ultrafine particle monitor model 651 for potential network use (ambient or near-roadway). Durability will be measured by the continued operation of the instruments over a four-month period without requiring major repairs. Instrument precision was also assessed by calculating intra-model variability.
In addition, one meteorological instrument was used to measure wind speed and direction to verify when the CPCs are downwind of the freeway. SCAQMD also obtained weigh-in-motion (WIM) data from the California Department of Transportation’s on-road sensors located near the study site. WIM data will be used to determine the type and number of vehicles passing by the study site during the study period.
Data from the collocated instruments were analyzed for precision. The precision of the instruments were found to be well within +/- 10 percent with R2 > 0.98 for all three monitors and calculated based on U.S. EPA’s requirement of calculating precision for continuous PM2.5 (40 CFR Part 58 Appendix A 4.3.1).
References
Eon S. Lee, Andrea Polidori, Michael Koch, Philip M. Fine, Ahmed Mehadi, Donald Hammond, Jeffery N. Wright, Antonio. H. Miguel, Alberto Ayala, Yifang Zhu, “Water-based condensation particle counters comparison near a major freeway with significant heavy-duty diesel traffic,” Atmospheric Environment 68 (2013) pp. 151-161.