National Institute for Occupational Safety and Health

“ The working range is 0.00025 to 0.01 mg/m 3 for a 200-L air sample and 0.002 to 0.07 mg/m 3 for a 30-L air sample. This method collects particulate arsenic only; if arsenic trioxide vapor is present, use the sampler in Method 7901. This is an elemental analysis, not compound specific. Volatile organic arsenic compounds, As 2O 3 vapor, and arsine are not collected efficiently by this sampling method. ”

“ Open the cassette filter holders and transfer the samples and blanks to clean beakers. NOTE: Analyze the backup pad separately if qualitative indication of As 2O 3 vapor is desired. Use Method 7901 if quantitative collection of As 2O 3 vapor is desired. Add 5 mL ashing acid and cover with a watchglass. Heat on hotplate (140 °C) until the solution is colorless. Add 1 mL conc. HNO 3 and/or 70% HClO 4 drop by drop as needed to complete the ashing. Remove the watchglass. Heat on 140 °C hotplate until dense SO 3 fumes appear. Allow the mixture to cool. ”

“ Personal sampling pump, 1 to 3 L/min, with flexible connecting tubing. 3. Atomic absorption spectrophotometer with appropriate hydrogen burner head or quartz tube furnace, and arsenic hollow cathode lamp or EDL and arsine generation system. ”