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PHOSPORUS TRICHLORIDE

6402

PCl₃

MW: 137.33

CAS: 7719-12-2

RTECS: TH3675000

METHOD: 6402, Issue 2

EVALUATION: PARTIAL

Issue 1: 15 May 1985

Issue 2: 15 August 1994

OSHA : 0.5 ppm

NIOSH: 0.2 ppm; STEL 0.5 ppm

ACGIH: 0.2 ppm; STEL 0.5 ppm

(1 ppm = 5.61 mg/m³ @ NTP)

PROPERTIES: liquid; d 1.574 g/mL @ 21 °C;

BP 76 °C; MP -112 °C; VP 13 kPa

(100 mm Hg; 13% v/v) @ 21 °C

SYNONYMS: phosporous chloride.

SAMPLING

MEASUREMENT

SAMPLER:

BUBBLER (15 mL H₂O)

FLOW RATE:

0.05 to 0.2 L/min

VOL-MIN:

11 L @ 0.5 ppm

-MAX:

100 L

SHIPMENT:

ship in sealed bubblers

SAMPLE

STABILITY:

unknown

FIELD BLANKS:

2 to 10 field blanks per set

ACCURACY

RANGE STUDIED:

ca. 3.1 mg/m³ [1]

BIAS:

not significant [1]

OVERALL PRECISION (SrT):

unknown

ACCURACY:

not determined

METHOD:

VISIBLE SPECTROPHOTOMETRY

ANALYTE:

molybdenum blue

COLOR DEVELOPMENT:

3 mL Br 2 water + 5 mL Na 2MoO 4 + 2 mL hydrazine sulfate → molybdenum blue

WAVELENGTH:

830 nm

CALIBRATION:

KH 2PO 4 solutions

RANGE:

0.03 to 0.5 mg PCl 3 per sample

ESTIMATED LOD: 3 µg PCl 3 per sample

PRECISION (Sr):

0.06 @ 0.03 to 0.14 mg PCl 3 per sample [1]

APPLICABILITY: The working range is 0.2 to 14 ppm (1.2 to 80 mg/m 3) for a 25-L air sample.

INTERFERENCES: Phosphorus (V) compounds do not interfere. The sample solutions are stable to oxidation by air during sampling [1].

OTHER METHODS: This revises P&CAM 305 [2].

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