National Institute for Occupational Safety and Health

“ Concentrated nitric acid is an irritant and may burn skin. Perform all acid digestions in a fume hood. Hydrogen peroxide is a strong oxidizing agent, a strong irritant, and corrosive to the skin. Wear gloves and eye protection.
SAMPLING: 1. Calibrate each personal sampling pump with a representative sampler in line. 2. Sample at an accurately known flow rate between 1 and 4 L/min for up to 8 h for a total sample size of 1 to 1500 L for TWA measurements. ”

“ Perform a matrix spike of a sample occasionally to check for matrix interferences. If an adequate recovery is not obtained (85 to 115%) , an alternate method of analysis should be used, such as flame AAS or ICP. MEASUREMENT: 12. Set spectrophotometer as specified by the manufacturer and to conditions on page 7105-1. NOTE: An alternate wavelength is 217.0 nm [3] . Analyses at 217.0 nm have slightly greater sensitivity, but poorer signal-to-noise ratio compared to 283.3 nm. ”

“ This revises and replaces P&CAM 214 (2) . Method 7300 (ICP-AES) is an alternate analytical method. Method 7505 is specific for lead sulfide by X-ray diffraction. Method 7082 is a flame AAS method, with a higher working range. ”