Page:NIOSH Manual of Analytical Methods - 7504.pdf/1

 VANADIUM OXIDES

(1): V2O5 MW: (2): V2O3 (3): NH4VO3

(1): 181.88 (2): 149.88 (3): 116.99

METHOD: 7504, Issue 2

CAS: (1) 1314-62-1 (2) 1314-34-7 (3) 7803-55-6

7504

RTECS: (1) YW2450000 (dust) (1) YW2460000 (fume) (2) YW3050000 (3) YW0875000

EVALUATION: PARTIAL

C 0.5 mg/m 3 (as V) (V 2O 5 Dust); C 0.1 mg/m 3 (as V) (V 2O 5 Fume); 1 mg/m 3 (FeV) NIOSH: C 0.05 mg/m 3/15 min (as V 2O 5) ACGIH: 0.05 mg/m 3 (respirable, as V 2O 5) OSHA:

Issue 1: 15 August 1987 Issue 2: 15 August 1994

PROPERTIES: solids; MP 658 °C (1); MP 1967 °C (2)

SYNONYMS: (1): vanadic anhydride; vanadium pentoxide; (2): vanadic oxide; vanadium sesquioxide; vanadium trioxide. SAMPLING SAMPLER:

FLOW RATE:

MEASUREMENT

CYCLONE + FILTER (10-mm cyclone or Higgins-Dewell (HD) + 5-µm PVC membrane) HD cyclone: 2.2 L/min nylon cyclone: 1.7 L/min

VOL-MIN: -MAX:

200 L @ 0.5 mg/m 3 1000 L

SHIPMENT:

routine

SAMPLE STABILITY:

stable

BLANKS:

2 to 10 field blanks per set

BULK SAMPLE:

X-RAY POWDER DIFFRACTION

ANALYTE:

vanadium pentoxide, vanadium trioxide, or ammonium metavanadate

SAMPLE PREPARATION:

Cu target X-ray tube optimize for intensity; 1° 2 θ slit graphite monochromator scintillation detector integrated intensity with background subtraction slow step scan (10 seconds/0.02° 2 θ)

CALIBRATION:

standard suspensions deposited on Ag filter

RANGE:

0.1 to 2 mg V per sample

of

analytes

ESTIMATED LOD: Table 1

RANGE STUDIED:

(1): 0.8-2.6 mg/m 3; (2): 0.2-2.6 mg/m 3 [1]

BIAS:

Table 1

ˆ ): OVERALL PRECISION (S rT

dissolve filter in tetrahydrofuran; redeposit on Ag filter

XRD:

high-volume respirable (preferred) or settled dust to identify interferences

ACCURACY

ACCURACY:

METHOD:

PRECISION (Sr):

Table 1

Table 1 ± 26 to 62%

APPLICABILITY: The working range is 0.2 to 4 mg/m 3 (as V) for a 500-L air sample. The method will determine V 2O 5, V2O 3, and NH 4VO 3 separately on the same sample. INTERFERENCES: α-Quartz (likely to be found in mineral samples) interferes (Table 1) but alternative diffraction lines are available. Most other compounds likely to be in the sample do not interfere [1].

OTHER METHODS: This replaces P&CAM 364 [2]. Methods S391 (Vanadiaum by graphite atomizer AAS) and 7300 (Elements by ICP-AES) determine total V.

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