Journal Article

Field Method Comparison between Passive Air Samplers and Continuous Monitors for VOCs and NO2 in El Paso, Texas

Gonzales, Melissa, Smith, Luther A., Mukerjee, Shaibal, Noble, Christopher A., Norris, Gary A., Özkaynak, A. Halûk, Neas, Lucas M., Morandi, Maria T.

2004

Overview

This study evaluates the performance of Model 3300 Ogawa Passive Nitrogen Dioxide (NO 2 ) Samplers and 3M 3520 Organic Vapor Monitors (OVMs) by comparing integrated passive sampling concentrations to averaged hourly NO 2 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 NO 2 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 NO 2 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.

• Publisher: Taylor & Francis Group,Air & Waste Management Association
• Subject: Air Pollutants - analysis / Applied sciences / Automation / Environmental Monitoring - methods / Exact sciences and technology / Luminescent Measurements / Models, Statistical / Nitrogen Dioxide - analysis / Organic Chemicals - analysis / Pollution / Sensitivity and Specificity / Texas