Ten NIOSH Analytical Methods - Tantalum.
NIOSH 1979 Apr:24 pages
The NIOSH validated method for the determination of tantalum (7440257) is described. One hundred liters of air (flow rate at 1.5 liters per minute) is drawn through a mixed cellulose ester membrane filter to trap the tantalum. The sample and filter are digested successively with 3 milliliters (ml) concentrated nitric-acid twice, 3ml nitric-acid plus 5 drops concentrated perchloric-acid, 1ml nitric-acid plus 5ml of 5 percent hydrofluoric-acid, evaporating to dryness between each step, except the last which is evaporated until only a droplet of solution remains. Three to 5ml of 5 percent hydrofluoric-acid are added. After cooling, the solution is added to a 10ml volumetric flask and filled to the mark with 5 percent hydrofluoric-acid. The solution is analyzed by a plasma emission spectrometer at the wavelength of 3320 angstroms. Tantalum concentration is determined by comparing with a calibration curve obtained by analyzing standards having concentrations equal to 0.5, 1, and 2 times the OSHA standard of 5 milligrams per cubic meter (mg/m3). The method is useful for determining tantalum concentrations of 2.5 to 10.0mg/m3 with a standard deviation of
NIOSH-Author; NIOSH-Analytical-Method; Analytical-Method; Standards; Sampling; Standards-Completion-Program; SCP; Set-7; Spectrographic-analysis; Heavy-metals;
NTIS Accession No.
Division of Physical Sciences and Engineering, NIOSH, U.S. Department of Health and Human Services, Cincinnati, Ohio, 24 pages, 5 references