title: Laboratory validation and field verification of a new passive colorimetric air monitoring badge for sampling hydrogen sulfide in air.
abstract: The Pro-Tek passive colorimetric air monitoring badge for personal or area sampling of hydrogen sulfide is described. The badge has been validated over the range of 1.8 to 164 ppm-hours (0.23-21 ppm on an 8-hour TWA basis). It has an overall accuracy throughout this range of +/- 15.9% and meets the NIOSH accuracy criteria for an analytical and sampling method. The colorimetric analytical method used is based on the Texas Air Control Board's Molybdenum Blue method. Color-activated exposed badge solutions are read out on a standard laboratory spectrophotometer using 1 centimeter (10 mm) cells. Variations in exposure temperature (between 10 degrees and 40 degrees C), relative humidity, and face velocity (between 2 and 250 ft/min) do not affect badge performance. Unexposed badges are stable for more than 12 months refrigerated and for two months at room temperature.
mesh_terms: D000395:Air Pollutants, Occupational / Q000032:analysis*; D003124:Colorimetry / Q000295:instrumentation / Q000379:methods*; D006862:Hydrogen Sulfide / Q000032:analysis*
chemical_list: D000395:Air Pollutants, Occupational; D006862:Hydrogen Sulfide