Page:NIOSH Manual of Analytical Methods - 7704.pdf/2

 BERYLLIUM in Air: METHOD 7704, Issue 1, dated 06 April 2007 – Page � of 6 REAGENTS: 1.	Ammonium bifluoride.* 2.	Ethylenediaminetetraacetic acid (EDTA), disodium salt, dihydrate. 3.	10-Hydroxybenzo[h]quinoline-7-sulfonate (HBQS) [5]. 4.	L-Lysine monohydrochloride. 5.	Sodium hydroxide.* 6.	Water, deionized. 7.	Dissolution solution:* aqueous ammonium bifluoride, 10 g/L (prepared by dissolving ammonium bifluoride in deionized water). 8.	Detection solution:* 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).	 9.	Beryllium standard solution,* 1,000 mg/L (commercially available).	10.	Beryllium-spiked media* (commercially available).
 * See SPECIAL PRECAUTIONS.

EQUIPMENT: 1.	Sampler: membrane filter, mixed cellulose ester (MCE) or nylon, 0.8 µm pore size, 25- or 37-mm diameter. 2.	Personal sampling pump, 1 L/min to 4 L/min, with clamps and flexible connecting tubing. 3.	Portable ultraviolet/visible (UV/Vis) fluoro­ meter, with excitation lamp (λ = 380 nm) and time-integrating visible detector (400 nm to 700 nm, λmax ≈ 475 nm) or optical filters for appropriate wavelengths (excitation of 360 nm to 390 nm; emission of ≈475 nm, with full width at half maximum of less than ±10 nm). 4.	Mechanical agitator, shaker, or rotator. 5.	Hot block (for beryllium oxide extraction). 6.	Fluorescence cuvettes, disposable, 10 mm diameter, transparent to UV/Vis radiation. 7.	Centrifuge tubes, plastic, 15 mL.	 8.	Syringe filters, nylon, 0.45 µm pore size, 13- or 25-mm diameter, in plastic housings. NOTE:	Polytetrafluoroethylene (PTFE) filters are unsuitable for this method. 9.	Pipettors, mechanical, of assorted sizes. 10.	Pipet tips, plastic, disposable, of assorted sizes. 11.	Labware, plastic (e.g., beakers, flasks, graduated cylinders), of assorted sizes. 12.	Tweezers, plastic or plastic-coated. 13.	Laboratory wipes. 14.	Personal protective wear (e.g., respirators, gloves, lab coats, safety eyewear) as needed.

SPECIAL PRECAUTIONS: Wear appropriate personal protection during sampling activities and analysis. It is essential that suitable gloves, eye protection, laboratory coat, etc., be used when working with the chemicals. Perform sample preparation and analysis in a clean, well-ventilated area that is well removed from any possible beryllium contamination. Any area affected by the dissolution or detection solutions must be immediately washed with plenty of water. Ammonium bifluoride will etch glass, so it is essential that all ammonium bifluoride solutions be contained in plastic labware. Avoid exposure by contact with skin or eyes, or by inhalation of vapor. SAMPLING: 1.	Calibrate each personal sampling pump with a representative sampler in line. 2.	Sample at an accurately known flow rate between 1 L/min and 4 L/min for a total sample size of 240 L to 2,000 L for TWA measurements. Do not exceed a filter loading of ≈2 mg total dust. 3.	After sampling, remove the filters from the cassettes using clean tweezers, and place into labeled 15 mL plastic centrifuge tubes. SAMPLE PREPARATION: 4.	Add 5 mL of the dissolution solution (ammonium bifluoride, 10 g/L) to each 15 mL centrifuge tube containing an air filter sample, and cap each tube. Updated: 04/06/2007

NIOSH Manual of Analytical Methods (NMAM), 5th Edition (Electronic)