Page:NIOSH Manual of Analytical Methods - 6001.pdf/1

 ARSINE

AsH3

MW: 77.95

METHOD: 6001, Issue 2

CAS: 7784-42-1

6001

RTECS: CG6475000

EVALUATION: FULL

OSHA : 0.05 ppm NIOSH: C 0.002 mg/m 3/15 min; carcinogen ACGIH: 0.05 ppm; carcinogen (1 ppm = 3.19 mg/m 3 @ NTP)

Issue 1: 15 May 1985 Issue 2: 15 August 1994

PROPERTIES: gas; d 3.484 g/L @ 20 °C; BP -62.5 °C; MP -116.3 °C

SYNONYMS: hydrogen arsenide; arsenic trihydride.

SAMPLING

MEASUREMENT

SAMPLER:

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

TECHNIQUE:

ATOMIC ABSORPTION, GRAPHITE FURNACE

FLOW RATE:

0.01 to 0.2 L/min

ANALYTE:

arsenic

VOL-MIN: -MAX:

0.1 L @ 0.05 ppm 10 L

DESORPTION:

1 mL 0.01 M HNO 3 ; 30 min in ultrasonic bath

SHIPMENT:

routine

MATRIX MODIFIER:

Ni2+, 1000 µg/mL

SAMPLE STABILITY:

at least 6 days @ 25 °C [1]

WAVELENGTH:

193.7 nm; D 2 or H 2 correction

BLANKS:

2 to 10 field blanks per set

GRAPHITE FURNACE:

DRY: 40 sec @ 110 °C; CHAR: 15 sec @ 1200 °C; ATOMIZE 7 sec @ 2540 °C

INJECTION:

50 µL

CALIBRATION:

As(III) in 0.01 M HNO 3 with 100 mg charcoal present

RANGE:

0.01 to 0.3 µg per sample [2]

ACCURACY RANGE STUDIED:

BIAS:

0.09 to 0.4 mg/m 3 [1] (10-L samples); 0.001 to 0.01 mg/m 3 [2] -6.13% at 0.01 to 0.2 L/min rates [1]; -11% @ 0.876 L/min [2]

ˆ ): 0.087 [2] OVERALL PRECISION (S rT ACCURACY:

± 23.2%

ESTIMATED LOD: 0.004 µg per sample PRECISION (Sr):

0.060 @ 0.012 to 0.11 µg per sample [2]

APPLICABILITY: The working range is 0.0003 to 0.06 ppm (0.001 to 0.2 mg/m 3 ) for a 10-L air sample. This is an elemental analysis and is not compound-specific.

INTERFERENCES: Use background correction to control molecular absorption. Other arsenic compounds (gases or aerosols) may be collected on the sampler and would be erroneously reported as arsine. A cellulose ester filter in front of the ch arcoal tube may be used to remove aerosols [3,4]. The effect of relative humidity on the capacity of charcoal for arsine has not bee n studied.

OTHER METHODS: This method combines and replaces P&CAM 265 [5] and S229 [6] for arsine.

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