METHYL ACETATE
CH3COOCH3
MW: 74.08
METHOD: 1458, Issue 2
CAS: 79-20-9
1458
RTECS: AI9100000
EVALUATION: FULL
OSHA : 200 ppm NIOSH: 200 ppm; STEL 250 ppm ACGIH: 200 ppm; STEL 250 ppm (1 ppm = 3.03 mg/m 3)
PROPERTIES:
Issue 1: 16 December 1974 Issue 2: 15 August 1994
liquid; d = 0.9244 g/mL @ 25 °C; BP = 54.05 °C; VP 23 kPa (173 mm Hg) @ 20 °C; vapor density (air = 1) 2.8
SYNONYMS: acetic acid methyl ester; methyl acetic ester; methyl ethanoate
SAMPLING SAMPLER:
MEASUREMENT
SOLID SORBENT TUBE (coconut shell charcoal, 100 mg/50 mg)
TECHNIQUE:
GAS CHROMATOGRAPHY, FID
ANALYTE:
methyl acetate
FLOW RATE:
0.01 to 0.2 L/minute
EXTRACTION:
1 mL CS 2
VOL-MIN: -MAX:
0.2 L @ 200 ppm 10 L
INJECTION VOLUME: 1 µL
SHIPMENT:
refrigerated
SAMPLE STABILITY:
at least 6 days @ 5 °C
BLANKS:
2 to 10 field blanks per set
ACCURACY RANGE STUDIED:
343 to 1130 mg/m 3 [1] (7-L samples)
BIAS:
7.2%
ˆ ): 0.0547 [1] OVERALL PRECISION (S rT ACCURACY:
± 16.8%
TEMPERATURE-INJECTOR: -DETECTOR: -COLUMN:
250 °C 300 °C 35 °C (2 min) to 150 °C (10 °C/min)
COLUMN:
DB-wax; 30 m, 0.32-mm ID, 1-µm film thickness
CARRIER GAS:
He, 1 mL/min;
MAKEUP GAS:
N 2, 30 mL/min
CALIBRATION:
solutions of methyl acetate in CS 2
RANGE:
7 µg to 1000 µg [2]
ESTIMATED LOD:
2 µg [2]
PRECISION (Sr):
0.036 @ 20 to 876 µg per sample [2]
APPLICABILITY: The working range is 0.3 to 1330 ppm (1 to 440 mg/m 3) for a 7-L air sample [1]. The method may be adapted for other esters with appropriate changes in chromatographic conditions.
INTERFERENCES: Any compounds with similar retention times.
OTHER METHODS: This revises Method S42 [1]. Improved recovery of analyte may be achieved with the addition of 5% butyl carbitol to the CS 2 desorption procedure [3,4].
NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94
