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INVESTIGATION OF THE PERFORMANCE OF SULFATION AND NITRATION PLATES
Citation:
Sickles, J.E., II, AND R. Michie. INVESTIGATION OF THE PERFORMANCE OF SULFATION AND NITRATION PLATES. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/3-84/073.
Description:
An inexpensive method for measuring atmospheric pollutants which has been in use for several decades is the passive reactive monitor. Such a device contains a reactive substance which is exposed to the ambient air for a period of time. The pollutants in the surrounding air react with the reactive surface of the monitor. A quantitative chemical determination is made of the reaction product. A calibration factor is then applied to estimate the pollutant concentration in the ambient air averaged over the exposure period. Passive monitors, known as sulfation and nitration plates, are available from commercial suppliers. The objective of this study was to evaluate the performance of commercial sulfation and nitration plates. The sensitivity of plate calibration factors to pollutant concentration (SO2 and NO2), simulated wind, speed, humidity, and temperature was determined. Test results indicate, for sulfation and nitration plates, that sulfation calibration factors are extremely sensitive to wind speed. A slight effect of relative humidity was observed on calibration factors for both types of plates. Nitration calibration factors are also extremely sensitive to concentration and temperature.