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HEXACHLOROBUTADIENE: METHOD 2543, Issue 2, dated 15 August 1994 - Page 3 of 3

10.

c. Cap the tube. Allow to stand overnight. d. Desorb (steps 5 through 7) and analyze with working standards (steps 11 and 12). e. Prepare graphs of DE vs. µg hexachlorobutadiene recovered. Analyze three quality control blind spikes and three analyst spikes with each subsequent set from the same lot to ensure that the calibration graph and DE graph are in control

MEASUREMENT: 11. 12.

Set gas chromatograph to conditions given on p. 2543-1. Inject a 1 µL sample aliquot. Measure and record peak area. NOTE: If peak area is above linear range of the working standards, dilute, reanalyze, and apply the appropriate dilution factor in the calculations.

CALCULATIONS: 13.

14.

Determine the mass, µg (corrected for DE) of HCBD found in the sample front (W f) and back (W b) sorbent sections and in the average media blank, front (B f) and back (B b) sorbent sections. NOTE: If W b > W f/10, report breakthrough and possible sample loss. Calculate the concentration of HCBD in the actual air volume, V (L), at the sampling site:

EVALUATION OF METHOD: This method was validated over the range 0.01 to 2 mg/m 3 at 25 °C to 28 °C at a relative humidity of 90% or greater using a 3-L sample [1]. Generation samples at four concentration levels gave an average mean recovery of 100.5% with an overall precision, SˆrT, of 0.09 [3]. Desorption efficiency (DE) of HCBD from XAD-2 tubes was 100% at a loading of 0.0167 µg per sample [3]. Samples showed good storage stability for 28 days if stored @ 0 °C after the seventh day [3].

REFERENCES: [1] [2] [3]

Hexachlorobutadiene, NIOSH Method P&CAM 307, 1979. Imagawa, T. and Miyazaki, A., Formation of hexachlorobutadiene and related compounds from chloroform in a flame ionization detector, Bunski Kagaku, 36(2), 118-120, 1987. Backup Data Report for Hexachlorobutadiene, NIOSH Contract 210-78-0012.

METHOD REVISED BY: S.M. Pendergrass, NIOSH/DPSE/MRSB; P&CAM 307 originally validated under NIOSH Contract 21078-0012.

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

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