Field Method Comparison between Passive Air Samplers and Continuous Monitors for VOCs and NO2 in El Paso,Texas |
| |
| Authors: | Shaibal Mukerjee Luther A Smith Gary A Norris Maria T Morandi Melissa Gonzales Christopher A Noble |
| |
| Institution: | 1. Exposure Modeling Research Branch, Human Exposure and Atmospheric Sciences Division, National Exposure Research Laboratory, Office of Research and Development , U.S. Environmental Protection Agency , Research Triangle Park , North Carolina , USA mukerjee.shaibal@epa.gov;3. ManTech Environmental Technology, Inc. , Durham , North Carolina , USA;4. Environmental Characterization and Apportionment Branch, Human Exposure and Atmospheric Sciences Division, National Exposure Research Laboratory, Office of Research and Development , U.S. Environmental Protection Agency , Research Triangle Park , North Carolina , USA;5. Houston Health Science Center, School of Public Health, University of Texas , Houston , Texas , USA;6. Department of Internal Medicine , University of New Mexico School of Medicine , Albuquerque , New Mexico , USA;7. Center for Aerosol Technology, RTI International , Research Triangle Park , North Carolina , USA |
| |
| Abstract: | Abstract This study evaluates the performance of Model 3300 Ogawa Passive Nitrogen Dioxide (NO2) Samplers and 3M 3520 Organic Vapor Monitors (OVMs) by comparing integrated passive sampling concentrations to averaged hourly NO2 and volatile organic compound (VOC) measurements at two sites in El Paso, TX. Sampling periods were three time intervals (3-day weekend, 4-day weekday, and 7-day weekly) for three consecutive weeks. OVM concentrations were corrected for ambient pressure to account for higher elevation. Precise results (<5% relative standard deviation, RSD) were found for NO2 measurements from collocated Ogawa samplers. Reproducibility was lower from duplicate OVMs for BTEX (benzene, toluene, ethylbenzene, and xylene isomers) VOCs (≥7% RSD for 2-day samples) with better precision for longer sampling periods. Comparison of Ogawa NO2 samplers with chemiluminescence measurements averaged over the same time period suggested potential calibration problems with the chemiluminescence analyzer. For BTEX species, generally good agreement was obtained between OVMs and automated-gas chromatograph (auto-GC) measurements. The OVMs successfully tracked increasing levels of VOCs recorded by the auto-GCs. |
| |
| Keywords: | |
|
|
