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AMINES, AROMATIC: METHOD 2002, Issue 2, dated 15 August 1994 - Page 4 of 6 CALCULATIONS: 13. Determine the mass, mg (corrected for DE) of analyte 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. 14. Calculate concentration, C, of analyte in the air volume sampled, V (L):

EVALUATION OF METHOD: Precisions, biases and recoveries listed below were determined by analyzing generated atmospheres containing one-half, one and two times the OSHA standard [1]. Generated concentrations were independently verified. Breakthrough of the front section of the silica gel tube was not observed after sampling a dry test atmosphere. The first three analytes were stable on silica gel for at least one week. Method S164 using collection on activated charcoal was also developed for N,N-dimethylaniline [3].

Breakthrough Sampling volume in dry air at concentration (L) (mg/m 3) Substance Aniline

Range mg/m 3 (volume)

Bias (%)

Overall Precision ˆ rT ) (S

Accuracy (%)

Measurement Range Precision (mg) (Sr)

Desorption efficiency

>44.4

38

9.5-38.2 (20 L)

-4.9

0.060

±15.1

0.20-0.82

0.013

0.980-1.00

o-Toluidine

>221.3

47

11.7-46.9 (50 L)

-1.5

0.060

±12.0

0.55-2.2

0.032

0.970-0.983

2,4-Xylidine

>44.4

50

12.5-50.0 (20 L)

-1.2

0.057

±11.2

0.25-1.01

0.021

0.959-1.015

N,N-Dimethyl-ptoluidine

9.4-30.0 (100 L)

0.47

0.035

0.88

N,N-Dimethylaniline

-7.9

0.090

±16.0

0.05-3.0

0.997 (1.9-mg samples)

  • Not determined

REFERENCES: [1]

[2] [3] [4] [5]

Documentation of the NIOSH Validation Tests, S162, S164, S168, S310, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-185 (1977), available as GPO Stock

  1. 017-033-00231-2 from Superintendent of Documents, Washington, DC 20402.

UBTL, Inc., Sequence #2300-S, Aniline (May 15, 1980), and Sequence #2551-M, o-Toluidine (August 28, 1980) (NIOSH, unpublished). NIOSH Manual of Analytical Methods, 2nd ed., Vol. 3, S162, S164, S168, S310, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-157-C (1977). Ibid., Vol. 4, P&CAM 280, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 78-175 (1978). Ibid., Vol. 1, P&CAM 168, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 77-157-A (1977). NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94