National Institute for Occupational Safety and Health

“ Prepare a calibration graph of fluorescence intensity vs. beryllium concentration (ng/mL) in the stock standard. NOTE:
To test a range of 0.05 μg to 4 μg of beryllium on the sampling media, beryllium stock standard solutions are made up using beryllium spectrometric standards diluted with the ammonium bifluoride dissolution solution. A recommended series of stock standard solutions is (800, 200, 40, 10, and 0) ng/mL. As with the samples, the stock standards are prepared for analysis by adding 0.1 mL of beryllium stock standard into 1.9 mL of detection solution (20-fold dilution) . ”

“ 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. ”

“ Experiments were conducted using an Ocean Optics® portable fluorescence device with the following components: USB 200 spectrometer with spectral grating #2 (UV/Vis 600) , LS-1 lamp (380 nm) in LS-450 housing, UV-2 casting, OFLV linear filter 200-850, L2 collection lens and slit-200. Tests were carried out in relative irradiance mode using 2- or 5-second integration times. The method was evaluated using beryllium oxide spiked onto mixed cellulose ester (MCE) filters at levels of (0, 0.02, 0.1, 0.2, 0.3, 0.4, 1.5, 3.0, and 6.0) μg (five samples at each level) . ”