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
