Page:NIOSH Manual of Analytical Methods - 5037.pdf/2

 TRIORTHOCRESYL PHOSPHATE: METHOD 5037, Issue 1, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2. 3. 4. 5. 6.

EQUIPMENT:

Diethyl ether *, anhydrous, reagent grade. Triorthocresyl phosphate *, reagent grade. Hydrogen, purified. Compressed air, prefiltered. Nitrogen, purified. Calibration stock solution, triorthocresyl phosphate in diethyl ether.



See Special Precautions

1. Sampler: 37-mm mixed cellulose ester membrane filter (0.8-µm pore size) supported by cellulose backup pad in three-piece filter holder. 2. Personal sampling pump with flexible polyethylene or PTFE tubing. 3. Gas chromatograph equipped with a flame photometric detector, phosphorus filter, and column (p. 5037-1). 4. Electronic integrator or some other suitable method for measuring peak areas. 5. Tweezers. 6. Jars: 2-oz ointment jars for sample extraction, squat form with aluminum-lined screw caps. 7. Syringes, 10-µL and other convenient sizes. 8. Volumetric flasks, 10-mL and other convenient sizes. 9. Pipets, 10-mL and other convenient sizes.

SPECIAL PRECAUTIONS: Store diethyl ether away from heat, light, and sources of ignition in a wellventilated area. Do not leave container open. Diethyl ether can oxidize in air to form explosive peroxides, a reaction accelerated by light. Distillation and evaporation can concentrate unstable peroxides in the residue, a potentially explosive condition [12]. Triorthocresyl phosphate is more toxic than other tricresyl phosphate isomers and readily absorbed through the skin. Avoid contact of triorthocresyl phosphate with eyes, skin, and clothing [13,14]. Handle only in a fume hood.

SAMPLING: 1. 2. 3. 4.

Calibrate each personal sampling pump with the representative filter cassette in line. Remove cassette plugs and connect cassette filter to the personal sampling pump with flexible tubing. Sample at an accurately known flow rate of 1 to 3 L/min for a total sample size of 2 to 100 L. Firmly seal collected sample cassettes with plugs. Pack securely for shipment.

SAMPLE PREPARATION: 5. 6. 7.

Transfer the filter and backup pad to an ointment jar using tweezers. Pipet 10.0 mL of diethyl ether into each jar. Seal the jar immediately to minimize evaporation. Allow samples to stand for at least 30 min with occasional agitation.

CALIBRATION AND QUALITY CONTROL: 8.

Calibrate daily with at least six working standards over the range of 0.05 to 24 µg per sample. a. Prepare a stock solution by weighing an appropriate quantity of triorthocresyl phosphate into a volumetric flask and diluting to volume with diethyl ether. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94