Page:NIOSH Manual of Analytical Methods - 7301.pdf/3
ELEM ENT S by ICP (Aqu a Reg ia Ashing): MET HO D 730 1, Issue 1, dated 15 M arch 200 3 - Page 3 o f 8 CALIBRATION AND QUALITY CONTRO L: 12. Calibrate the spectrometer according to the manufacturer’s recomm endations. NOTE: Typically, an acid blank and 1.0 µg/m L multielement working standards are used. The following multielement combinations are chemically compatible in 5% Aqua Regia: a. Al, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, La, In, Na b. Ag, K, Li, Mg, Mn, Ni, P, Pb, Se, Sr, Tl, V, Y, Zn, Sc c. Mo, Sb, Sn, Te, Ti, W , Zr d. Acid blank 13. Analyze a standard for every ten samples. 14. Check recoveries with at least two spiked media blanks per ten samples.
MEASUREMENT: 15. Set spec trome ter to conditions spe cified by manufac turer. 16. Analyze standards, samples, and blanks. NOTE: If the va lues for the sam ples are a bove the rang e of th e standa rds, dilute the solutions w ith dilution acid, reanalyze a nd apply the appropriate dilution fac tor in the calcula tions. If more sensitivity is required, the final sample volume may be held to 10.0 mL.
CALCULATIONS: 17. Obtain the solution concentrations for the sample, C s (µg/m L), an d the average m edia blank , C b (µg/m L), from the ins trum ent. 18. Using the solution volum es o f sam ple, V s (m L), and m edia blank , V b (mL), calculate the concentration, C (m g/m 3), of each elem ent in the air volum e sam pled, V (L):
NOT E: µg/L / m g/m 3
EVALUATION OF METHOD: The precision and recovery data were determined at approximately 3x and 10x the instrumental detection limits on com m ercially prepared s pike d filters [12] using 25 .0 m L as the final sample volume. The precision and recovery data, instrumental detection lim its, and ana lytical wave lengths are listed in Ta bles 3 and 4. In general, better recoveries were obtained from MCE filters than from PVC filters. The values in Tables 3 and 4 were determined with a Spectro Analytical Instruments model EOP opera ted according to m anufa cturer's instructions.
REFERENCES: [1] Millson M, Andrews R [2002]. Backup data report, Method 7301, unpublished report, NIOSH/DART. [2] Hull RD [1981]. Multielement Analysis of Industrial Hygiene Sam ples, NIO SH Internal Re port, presented at the American Industrial Hygiene Conference, Portland, Oregon. [3] NIOSH [1982]. NIOSH Manual of Analytical Methods, 2nd ed., V. 7, P&CAM 351 (Elements by ICP), U.S. Department of Health and Human Services, Publ. (NIOSH) 82-100. [4] NIOSH [1994]. Elem ents by ICP : Method 7300. In: Eller PM, Cassinelli ME, eds., NIOSH M anual of Analytical Me thod s, 4 th ed. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, DHHS (NIOSH) Publication No. 94-113. NIOSH Manual of Analytical Methods (NMAM), Fourth Edition