APPLICABILITY:
The working range is 0.2 to 8 ppm (0.5 to 20 mg/m 3) for a 100-L air sample. The method is applicable to STEL samples. SO2 is collected on the back (treated) filter. Sulfuric acid, sulfate salts, and sulfite salts are collected on the front f ilterand may be quantitated as total particulate sulfate.