Page:NIOSH Manual of Analytical Methods - 1602.pdf/2

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DIOXANE: METHOD 1602, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1.

2. 3.

4. 5. 6.

EQUIPMENT:

Eluent: carbon disulfide,* chromatographic quality, containing 0.1% (v/v) octane, decane, or other suitable internal standard. Dioxane, reagent grade.* Desorption efficiency (DE) stock solution, 0.1 mg/µL. Dilute 1 g dioxane to 10 mL with pentane. Helium, purified. Hydrogen, prepurified. Air, compressed, filtered.

See SPECIAL PRECAUTIONS.

1. Sampler: glass tube, 7 cm long, 4-mm ID, flame-sealed ends with plastic caps, containing two sections of activated (600 °C) coconut shell charcoal (front =100 mg; back = 50 mg) separated by a 2-mm urethane foam plug. A silylated glass wool plug precedes the front section and a 3-mm urethane foam plug follows the back section. Pressure drop across the tube at 1 L/min airflow must be less than 3.4 kPa. Tubes are commercially available. 2. Personal sampling pump, 0.01 to 0.2 L/min, with flexible connecting tubing. 3. Gas chromatograph, FID, integrator, and column (page 1602-1). 4. Vials, 2-mL, PTFE-lined caps. 5. Syringes, 10-µL and other convenient sizes for preparing standards, readable to 0.1-µL. 6. Volumetric flasks, 10-mL. 7. Pipet, 1-mL.

SPECIAL PRECAUTIONS: Carbon disulfide is toxic and a serious fire and explosion hazard (flash point = -30 °C). Dioxane is toxic, causing central nervous system depression and necrosis of liver and kidneys, as well as a skin irritant [6], and a suspect carcinogen [7]. Use personal protective equipment and work only in a 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. Sample at an accurately known flow rate between 0.01 and 0.2 L/min for a total sample size of 0.5 to 15 L. Cap the samplers. Pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Place the front and back sorbent sections of the sampler tube in separate vials. Discard the glass wool and foam plugs. Add 1.0 mL eluent to each vial. Attach cap to each vial. Allow to stand 30 min with occasional agitation.

CALIBRATION AND QUALITY CONTROL: 8.

Calibrate daily with at least five working standards over the range 0.01 to 7 mg dioxane per sample.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94