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OIL M IST, MIN ERA L: MET HO D 502 6, Issue 2, Rev. 15 M ay 1996 - Page 2 of 4 EQUIPMENT:

REAGENTS: 1. Carbon tetrachloride* (CCL4), reagent grade. 2. Stoc k m ineral oil standards , 20 m g/m L. W eigh 1.0 g of the bulk m ineral oil sam ple into a 50-m L volum etric flas k. D ilute to volume with CCl4. Prepare in duplicate.

  • See SPECIAL PRECAUTIONS

1. Sam pler: mem brane filter, 37-mm , 0.8-:m MCE, 5-:m PV C, 2-:m PT FE, or glass fiber filter, with cellulose backup pad in two-piece filter cassette. NOT E 1: High concentrations of oil mist may plug m em brane filters. Glass fibers filters have a higher capacity for oil mist and mem brane filters. NOT E 2: Hand le filters carefully with tweezers to avoid contam ination by skin oil. 2. Personal sa m pling pum p, 1 to 3 L/m in, with flexible connecting tubing. 3. Infrared spectrophotometer, doulble beam, dispersive, with scanning capability in the 32002700 cm -1 region, and two 10-m m spe ctrop hoto m eter c ells, infrared q uartz w ith PT FE sto ppers m ounte d in dem ounta ble cell holders. NOTE: Sta ndard glass cells m aybe used if infrared quartz cells are not available. 4. Vials, scintillation, 20-mL, with foil-lined or PT FE -lined c aps .* 5. Volum etric flas ks, 10-, 25-, an d 50 -m L.* 6. Volum etric pipet or reag ent dispense r, 10-m L.* 7. Pipets, 2- to 250-:L. 8. Tweezers.

  • Rinse glassware with CCl4. Air dry.

SPECIAL PRECAUTIONS: Carbon tetrachloride is a suspected human carcinogen. Handle in a fume hood.

SAMPLING: 1. Calibrate each personal sampling pump with a representative sampler in line. 2. Sam ple at a n ac curately kn own flow ra te in the rang e 1 to 3 L/m in for a total sam ple size of 20 to 500 L. NOTE: High concentrations of oil mist may plug membrane filters creating unacceptably high pressure drops. If this occurs, terminate sampling. 3. Collect 5 to 10 m L of unuse d, undiluted mineral oil in a vial. Subm it with sam ples for standard preparation.

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition