Page:NIOSH Manual of Analytical Methods - 1603.pdf/1

 ACETIC ACID

CH3COOH

MW: 60.05

METHOD: 1603, Issue 2

CAS: 64-19-7

1603

RTECS: AF1225000

EVALUATION: FULL

OSHA : 10 ppm NIOSH: 10 ppm; STEL 15 ppm ACGIH: 10 ppm; STEL 15 ppm (1 ppm = 2.46 mg/m 3 @ NTP)

Issue 1: 15 May 1989 Issue 2: 15 August 1994

PROPERTIES: liquid; d 1.049 g/mL @ 25 °C; BP 118 °C; MP 17 °C; VP 1.5 kPa (11.4 mm Hg) @ 20 °C; explosive range 5.4 to 16% v/v in air

SYNONYMS: glacial acetic acid; methane carboxylic acid; ethanoic acid

SAMPLING SAMPLER:

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

MEASUREMENT TECHNIQUE:

GAS CHROMATOGRAPHY, FID

ANALYTE:

acetic acid

FLOW RATE: 0.01 to 1.0 L/min

DESORPTION:

1 mL formic acid; stand 60 min

VOL-MIN: -MAX:

20 L @ 10 ppm 300 L

INJECTION VOLUME: 5 µL

SHIPMENT:

routine

SAMPLE STABILITY:

at least 7 days @ 25 °C

BLANKS:

2 to 10 field blanks per set

TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:

230 °C 230 °C 130 to 180 °C, 10°/min or 100 °C isothermal

CARRIER GASES: N 2 or He, 60 mL/min

ACCURACY RANGE STUDIED:

12.5 to 50 mg/m 3 [1] (173-L samples)

BIAS:

5.4%

COLUMN:

1 m x 4-mm ID glass; Carbopack B 60/80 mesh/3% Carbowax 20 M/0.5% H 3PO 4

CALIBRATION:

standard solutions of acetic acid in 88 to 95% formic acid

RANGE:

0.5 to 10 mg per sample

ESTIMATED LOD: 0.01 mg per sample [2]

ˆ ): 0.058 [1] OVERALL PRECISION (S rT ACCURACY:

± 15.5%

PRECISION (Sr):

0.007 @ 0.3 to 5 mg per sample [1,3]

APPLICABILITY: The working range is 2 to 40 ppm (5 to 100 mg/m 3) for a 100-L air sample. High (90% RH) humidity during sampling did not cause breakthrough at 39 mg/m 3 for 4.6 hrs [1].

INTERFERENCES: Formic acid contains a small amount of acetic acid which gives a significant blank value. High-purity formic acid must be used to achieve an acceptable detection limit. Alternate columns are 3-m glass, 2-mm ID, 0.3% SP-1000 + 0.3 % H 3PO 4 on Carbopack A and 2.4-m x 2-mm ID glass, 0.3% Carbowax 20M/0.1% H 3PO 4 on Carbopack C.

OTHER METHODS: This revises Method S169 [3].

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