National Institute for Occupational Safety and Health

“ Break ends of the sampler immediately before sampling. Attach sampler to personal sampling pump with flexible tubing. Sample at an accurately known flow rate between 0.05 and 0.5 L/min for a total sample size of 1 to 30 L. NOTE: Glutaraldehyde reacts with the 2,4-dinitrophenylhydrazine to form a hydrazone derivative which provides sample stability and UV chromophores for analysis. The hydro Immediately after sampling, cap the sample tubes, including blanks, and pack securely for shipment, include 10-20 unused tubes from the same lot to be used for standard preparation. ”

“ Prepare a calibration graph (peak area or height vs. concentration) . NOTE: Because the working standards are prepared on media blanks, no additional blank correction or extraction efficiency correction is necessary. ”

“ Glass tube, 110 mm long, 6-mm OD, flame-sealed ends and plastic caps containing two sections of silica gel coated with 2,4-dinitrophenylhydrazine HCl. The front section contains 300 mg, the back 150 mg, and sections are retained and separated by small plugs of silanized glass wool. (SKC 226-119 or equivalent) . NOTE: The hydrochloride salt provides an acid catalyst for the reaction of glutaraldehyde with the dinitrophenylhydrazine. Other acids may be used as catalyst. 2. Personal sampling pump, 0.05 to 0.5 L/min, with flexible connecting tubing. 3. ”