ACETONITRILE
CH3CN
MW: 41.06
METHOD: 1606, Issue 3
1606
CAS: 75-05-8
RTECS: AL7700000
EVALUATION: FULL
OSHA : 40 ppm NIOSH: 20 ppm ACGIH: 40 ppm; STEL 60 ppm (1 ppm = 1.68 mg/m3 @ NTP)
PROPERTIES:
Issue 1: 15 February 1984 Issue 3: 15 January 1998
liquid; d 0.783 g/mL @ 20 C; BP 82 C; VP 12 kPa ( 89 mm Hg) @ 25 C, explosive range 4.4 to 16% v/v in air
SYNONYMS: methyl cyanide, cyanomethane, ACN.
SAMPLING SAMPLER:
SOLID SORBENT TUBE (coconut shell charcoal, 400/200 mg)
FLOW RATE:
0.01 to 0.2 L/min
VOL-MIN: -MAX:
1 L @ 40 ppm 25 L
MEASUREMENT TECHNIQUE:
GAS CHROMATOGRAPHY, FID
ANALYTE:
acetonitrile
DESORPTION:
2 mL methylene chloride/methanol (85:15); ultrasonic bath for 45 minutes.
INJECTION VOLUME:
1 µL
SHIPMENT:
keep cold; pack securely for shipment.
SAMPLE STABILITY:
at least 30 days at 5 C
TEMPERATURE-INJECTION: 250 C -DETECTOR: 300 C -COLUMN: 35 C, hold 4 min; 12 C/min to 150 C
BLANKS:
2 to 10 field blanks per set
CARRIER GAS:
He, 2.4 mL/min
COLUMN:
capillary, fused silica, 30 m x 0.32-mm ID, 1µm film, crossbonded PEG, Stabilwax® or equivalent
CALIBRATION:
solutions of acetonitrile chloride/methanol (85:15)
0.071 [1,2]
RANGE:
2.6 to 2000 µg per sample [1, 2]
± 16.4%
ESTIMATED LOD: 0.8 µg per sample [1]
ACCURACY RANGE STUDIED:
39.2 to 275 mg/m3 [1]
BIAS:
4.0%
OVERALL PRECISION ( ACCURACY:
rT
):
PRECISION ( r):
in
methylene
0.015
APPLICABILITY: The working range is 0.06 to 7.4 ppm (0.1 to 12.5 mg/m3) for a 25-L air sample [1]. Large (400 mg/200 mg) charcoal tubes are required for analyte collection, since breakthrough volume is lower with smaller charcoal tubes [2]. Analyte capacity of the large charcoal tubes has not been determined under conditions of high relative humidity [3].
INTERFERENCES: Samples containing greater than 15% methanol or other alcohols.
OTHER METHODS:This method revises NMAM 1606 (dated 8/15/94) and is based on Method S165 [4]. In this method, a capillary GC column has replaced the original packed column. Improvements include but are not limited to the following: new and less hazardous desorption solvent, smaller volume of desorption solvent required, improved desorption efficiency (DE), and lower LOD/LOQ. A storage stability study was completed and was found acceptable at 98.5% after 30 days at 5 C.
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition
