Page:NIOSH Manual of Analytical Methods - 5025.pdf/2

 CHLORINATED DIPHENYL OXIDE: METHOD 5025, Issue 2, dated 15 August 1994 - Page 2 of 4 REAGENTS: 1. 2.

3. 4.

EQUIPMENT:

Isooctane, chromatographic quality. Calibration stock solution, 2 µg/µL chlorinated diphenyl oxide* in isooctane. Prepare in duplicate. Nitrogen, purified. Hydrogen, prepurified.



See SPECIAL PRECAUTIONS.

1. Sampler: cellulose ester membrane filter, 0.8-µm pore size, 37-mm diameter, supported by cellulose backup pad in two-piece polystyrene filter holder. 2. Personal sampling pump, 0.5 to 1.5 L/min, with flexible connecting tubing. 3. Gas chromatograph, electrolytic conductivity detector, effluent vent, integrator and column (page 5025-1). 4. Vials, 20-mL, PTFE-lined caps, for shipping filters. 5. Syringes, 25-µL, readable to 0.1 µL. 6. Volumetric flasks, 10-mL. 7. Pipet, 10-mL. 8. Tweezers.

SPECIAL PRECAUTIONS: Prolonged skin contact with chlorinated diphenyl oxide can cause chloracne; acute and chronic exposure can cause liver damage [3,4].

SAMPLING: 1. 2. 3.

Calibrate each personal sampling pump with a representative sampler in line. Sample at an accurately known flow rate between 0.5 and 1.5 L/min for a total sample size of 8 to 200 L. Within 1 h of sampling, using tweezers, carefully transfer the filter and backup pad to a vial.

SAMPLE PREPARATION: 4.

Pipet 10.0 mL isooctane into each vial containing a sample or blank filter and backup pad. Seal and gently swirl the vial to wet the filter and backup pad. Allow to stand 2 h.

CALIBRATION AND QUALITY CONTROL: 5.

6.

7.

Calibrate daily with at least six working standards. a. Add known amounts of calibration stock solution to isooctane in 10-mL volumetric flasks and dilute to the mark to obtain concentrations in the range 0.4 to 15 µg chlorinated diphenyl oxide/mL. b. Analyze with samples and blanks (steps 8 and 9). c. Prepare calibration graph (sum of areas of selected peaks vs. µg chlorinated diphenyl oxide). Determine recovery (R) at least once for each batch of filters used for sampling in the calibration range. Prepare three filters at each of five levels plus three media blanks. a. Deposit a known amount of calibration stock solution onto the filter. Allow filters to air dry. b. Store samples overnight in vials. c. Prepare (step 4) and analyze with working standards (steps 8 and 9). d. Graph R vs. µg chlorinated diphenyl oxide. Analyze three quality control blind spikes and three analyst spikes to ensure that the calibration graph and R graph are in control.

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