Page:NIOSH Manual of Analytical Methods - 2538.pdf/1

 ACETALDEHYDE by GC

CH3CHO

MW: 44.05

METHOD: 2538, Issue 1

CAS: 75-07-0

EVALUATION: UNRATED

OSHA : 200 ppm NIOSH: carcinogen; lowest feasible level ACGIH: C 25 ppm; suspect carcinogen (1 ppm = 1.801 mg/m 3 @ NTP)

PROPERTIES:

2538

RTECS: AB1925000 Issue 1:

15 August 1994

liquid; d 0.78 g/mL @ 20 °C; BP 20.4 °C; VP 100 kPa (750 mm Hg) @ 20 °C; explosive range 4 to 60% v/v in air

SYNONYMS: acetic aldehyde; ethanal.

SAMPLING SAMPLER:

MEASUREMENT

SOLID SORBENT TUBE [2-(hydroxymethyl)piperidine (2-HMP) on XAD-2, 450 mg/225 mg]

TECHNIQUE:

GAS CHROMATOGRAPHY, FID

ANALYTE:

oxazolidine derivative of acetaldehyde

FLOW RATE:

0.01 to 0.05 L/min

DESORPTION:

5 mL toluene, 60 min ultrasonic

VOL-MIN: -MAX:

1 L @ 100 ppm 12 L

INJECTION VOLUME:

1 µL, splitless

SHIPMENT:

routine

SAMPLE STABILITY:

TEMPERATURE-INJECTION: -DETECTOR: -COLUMN:

100% recovery after 21 days @ 0 °C [1]

BLANKS:

2 to 10 field blanks per set

250 °C 300 °C 70 °C 1 min; 6 °C/min to 110 °C (hold 2 min) 30 °C/min to 260 °C (hold 1 min)

CARRIER GAS:

He, 1 mL/min; makeup 29 mL/min

COLUMN:

wide-bore, fused-silica capillary, 15 m x 0.32-mm; 1-µm DB-1301 film

ACCURACY RANGE STUDIED:

180 to 720 mg/m 3 [2] (3-L samples)

CALIBRATION:

standard solutions of acetaldehyde on coated sorbent

BIAS:

0.2%

RANGE:

4 to 2200 µg per sample [2]

ˆ ): 0.12 [2] OVERALL PRECISION (S rT

ESTIMATED LOD: 2 µg per sample [1, 2]

ACCURACY:

PRECISION (Sr):

± 23.7%

0.090 @ 26 to 107 µg per sample [1]

APPLICABILITY: The working range is 0.74 to 407 ppm (1.3 to 730 mg/m 3) for a 3-L air sample.

INTERFERENCES: None identified. An alternative chromatographic column is a 2 m x 6-mm OD x 2-mm ID glass column containing 10% UCON 50-HB-5100 + 2% KOH on 80/100 Chromosorb W-AW.

OTHER METHODS: This is an adaptation of OSHA Method 68 [1], and is a convenient alternative to Method 3507.

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