Page:NIOSH Manual of Analytical Methods - 7704.pdf/1
BERYLLIUM in Air by Field-Portable Fluorometry Be
MW: 9.0121
METHOD: 7704, Issue 1
CAS: 7440-41-7
EVALUATION: PARTIAL
U.S. regulatory OELs OSHA: 2 µg/m3, ceiling 5 µg/m3, peak 25 µg/m3 MSHA: 2 µg/m3 DOE: 2 µg/m3 (action level 0.2 µg/m3) Other published OELs and guidelines OTHER: see Table 3
7704
RTECS: DS175000 Issue 1: 6 April 2007
PROPERTIES: solid, d 1.85 g/mL, MP 1,278 °C, VP 0 kPa (0 mm Hg) @ 25 °C
SYNONYMS: beryllium metal SAMPLING SAMPLER: FILTER (mixed cellulose ester or nylon membrane, 0.8 µm pore size, 25- or 37-mm diameter) FLOW RATE: (1 to 4) L/min VOL-MIN: -MAX:
240 L 2,000 L
SAMPLE STABILITY: stable 2 to 10 field blanks ACCURACY RANGE STUDIED:
not studied
BIAS:
not studied
OVERALL PRECISION (ŜrT): not studied ACCURACY:
TECHNIQUE:
FIELD-PORTABLE UV/VIS FLUOROMETRY
ANALYTE:
complex of hydroxybenzoquinoline sulfonate (HBQS) with beryllium
DISSOLUTION:
ammonium bifluoride (aqueous), 10 g/L
DETECTION SOLUTION:
SHIPMENT: routine
BLANKS:
MEASUREMENT
contains 63.4 µmol/L HBQS, 2.5 mmol/L EDTA, and 50.8 mmol/L lysine monohydrochloride; pH adjusted to 12.85 with 10 mol/L NaOH
DETECTOR:
excitation, 360 nm to 390 nm; emission, 400 nm to 700 nm (λmax ≈ 475 nm)
CALIBRATION:
beryllium standard solutions
RANGE:
(0.005 to 6) µg per filter [1]
ESTIMATED LOD: 0.00075 µg per filter [2] PRECISION (S¯r):
0.021 at ≈0.2 µg per filter, 0.076 at ≈1.5 µg per filter, 0.052 at ≈3 µg per filter
not studied
APPLICABILITY: The working range of the method is 0.005 µg/m3 to 6 µg/m3 for an air sample of 1,000 L. The analysis is for total beryllium and is not compound specific. INTERFERENCES: Minor interference from iron can result if iron concentrations are high. Samples high in iron demonstrate a yellow or gold coloration. This interference can be minimized by allowing the solution to sit for at least four hours, during which time the solution clears, and then filtering the sample extract before use. OTHER METHODS: Method 7300 (hot plate digestion and inductively coupled plasma atomic emission spectrometry) is an alternative (reference) procedure for the determination of elemental beryllium [3]. ASTM method D7202 is a similar procedure to detect elemental beryllium by fluorescence [4].
NIOSH Manual of Analytical Methods (NMAM), 5th Edition (Electronic)
Updated: 04/06/2007