Field comparison of two methods for the determination of NO2 concentration in air.
Jones-W; Palmes-ED; Tomczyk-C; Millson-M
Am Ind Hyg Assoc J 1979 May; 40(5):437-438
Two sampling methods for the determination of nitrogen-dioxide (10102440) in air were compared. The dosimeter method involved the measurement of a quantity of a gas transferred through a tube to a triethanolamine absorbent by molecular diffusion. The second method used a low flow pump to draw air through a glass tube containing two sections of a triethanolamine impregnated molecular sieve separated by an oxidizing section. To compare the two methods, air samples were collected in an underground salt mine in which diesel equipment was operated. For 16 sampling locations, the dosimeter method recorded nitrogen-dioxide concentrations ranging from 3.8 to 5.4 parts per million (ppm) while the tube method recorded a range of 3.2 to 5.5ppm. The authors conclude that the dosimeter method is somewhat more precise although both are suitable for industrial hygiene purposes. The passive dosimeters do not require a sampling pump, are lightweight, and reusable. The disadvantage of both techniques is that fluctuations of concentrations within the sampling period cannot be observed.
NIOSH-Author; Analytical-methods; Analytical-processes; Nitrogen-oxides; Air-sampling; Air-sampling-equipment; Quantitative-analysis
American Industrial Hygiene Association Journal