Page:NIOSH Manual of Analytical Methods - 1014.pdf/1

 METHYL IODIDE

CH3I

MW: 141.94

METHOD: 1014, Issue 2

CAS: 74-88-4

1014

RTECS: PA 9450000

EVALUATION: PARTIAL

OSHA : 5 ppm (skin) NIOSH: 2 ppm (skin; suspect carcinogen) ACGIH: C 0.2 (skin; suspect carcinogen) (1 ppm = 5.80 mg/m 3 @ NTP)

PROPERTIES:

Issue 1: 15 May 1985 Issue 2: 15 August 1994

liquid; d 2.28 g/mL @ 25 °C; BP 42.5 °C; MP -66 °C; VP 50 kPa (375 mm Hg; 49% v/v) @ 20 °C; not combustible

SYNONYMS: iodomethane

SAMPLING SAMPLER:

SOLID SORBENT TUBE (coconut shell charcoal, 100 mg/50 mg)

MEASUREMENT TECHNIQUE:

GAS CHROMATOGRAPHY, FID

ANALYTE:

methyl iodide

DESORPTION:

1 mL toluene, stand 8 h

INJECTION VOLUME:

5 µL

FLOW RATE: 0.01 to 1 L/min VOL-MIN: -MAX:

15 L @ 5 ppm 50 L

SHIPMENT:

routine

SAMPLE STABILITY:

unknown

TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:

BLANKS:

2 to 10 field blanks per set

CARRIER GAS:

nitrogen, 30 mL/min

COLUMN:

3 m x 3.2-mm OD stainless steel, packed with Chromosorb 101

CALIBRATION:

solutions of methyl iodide in toluene

RANGE:

0.5 to 5 mg per sample

ACCURACY RANGE STUDIED:

17 to 52 mg/m 3 [1] (53-L samples)

BIAS:

- 10.0%

ˆ ): 0.070 [1] OVERALL PRECISION (S rT ACCURACY:

200 °C 300 °C 190 °C

ESTIMATED LOD: 0.01 mg per sample [2] PRECISION (Sr):

0.045 @ 0.7 to 2.8 mg per sample [2]

± 20.03%

APPLICABILITY: The working range of this method is 10 to 100 mg/m during sampling will decrease breakthrough volume.

3

(1.7 to 17 ppm) for a 50-L air sample. High humidity

INTERFERENCES: None identified.

OTHER METHODS: This revises Method S98 [3].

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