Validation of a diffusive sampler for NO2.

A Hagenbjörk-Gustafsson; R Lindahl; J O Levin; D Karlsson

doi:10.1039/a902937k

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Validation of a diffusive sampler for NO2.

A Hagenbjörk-Gustafsson·R Lindahl·J O Levin·D Karlsson

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Abstract

A diffusive sampler for NO2, Willems badge, was validated in laboratory experiments and field tests. The collecting reagent for NO2 in the sampler is triethanolamine, and the analysis is based on a modified colorimetric method, the Saltzman method. The analysis was performed by a flow injection analysis (FIA) technique. The sampling rate for the sampler was determined to be 40.0 ml min-1. There was no effect of NO2 concentration or relative humidity on sampling rate, and the influence of sampling time was found to be small. The detection limit was 4 micrograms m-3 for a 24 h sample. The capacity is high enough to allow sampling of 150 micrograms m-3 for 7 days, which is twice the recommended Swedish short-term (24 h) guideline value as a 98-percentile over 6 months. In field tests, the sampler performed well, even at wind speeds higher than 2 m s-1, and at low temperatures. The overall uncertainty of the method was 24%. The sensitivity and capacity of the method also make it suitable for personal sampling for 2-8 h in working environments.

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Air Pollution Diffusion Environmental Monitoring Humans Nitrogen Dioxide Occupational Exposure Oxidants, Photochemical Sensitivity and Specificity Workplace Journal Article Research Support, Non-U.S. Gov't Validation Study

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A Hagenbjörk-Gustafsson, R Lindahl, J O Levin, D Karlsson. 1999. Validation of a diffusive sampler for NO2.. https://doi.org/10.1039/a902937k

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