National Institute for Occupational Safety and Health

“ Analyze a working standard for every five samples to check for instrument drift. c. Prepare a calibration graph (absorbance vs. μg arsenic) . Determine desorption efficiency (DE) at least once for each batch of charcoal used for sampling in the range 0.004 to 2 μg arsenic per sample. Prepare three tubes at each of five levels plus three media blanks. a. Remove and discard back sorbent section of a media blank sampler. b. Inject a known amount of pure arsine gas (or a certified gas mixture containing arsine) directly onto front sorbent section with a microliter syringe. ”

“ Arsine is extremely poisonous by inhalation. Handle in well-ventilated hood.
SAMPLING: 1. 2.
3. 4.
Calibrate each personal sampling pump with a representative sampler in line. Break the ends of the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. NOTE: Use a cellulose ester membrane prefilter if particulate arsenic compounds may be present [3,4] . Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 0.1 to 10 L. Cap the sampler with plastic (not rubber) caps and pack securely for shipment. ”

“ Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. Atomic absorption spectrophotometer with graphite furnace, non-pyrolytic tubes, background correction and electrodeless discharge (and power supply) or hollow cathode lamp for arsenic. Volumetric flasks, 1-L and 100-mL.* Micropipets, 5- to 500-μL.* Centrifuge tubes, 10- or 15-mL.* Ultrasonic bath. Centrifuge. Syringe, gas, 0.1-mL, readable to 1 μL.
Clean all glassware with conc. nitric acid and rinse thoroughly with distilled or deionized water before use.
SPECIAL PRECAUTIONS: Arsenic is a human carcinogen [7] . ”