National Institute for Occupational Safety and Health

“ Calibrate each personal sampling pump with a representative sampler in line. Transfer 15 mL 0.1 M hydrochloric acid to a bubbler. Connect outlet arm of bubbler to the glass-wool-packed tube (to prevent splashover into the pump) and then to the sampling pump with the flexible tubing. Sample at an accurately known rate between 0.5 and 1.5 L/min for a total air sample of 3 to 20 L. Remove bubbler stem and rinse with 0.1 M hydrochloric acid into bubbler body. Seal bubbler with an inert stopper for shipment in a suitable container in order to prevent damage during transit. ”

“ Monomethylhydrazine may be fatal if inhaled, swallowed or absorbed through skin contact [5,6] . Contact may cause burns to skin and eyes. Vapor may cause irritation to eyes, nose, throat, and skin. Handle with caution and use appropriate protective equipment. ”

“ Add 7.5 mL of phosphomolybdic acid solution to all standards and blank and bring the volume up to 25 mL with 0.1 M hydrochloric acid. Transfer aliquots of these solutions to large test tubes and heat to 87 °C for 50 min. Place test tubes under running tap water to cool before measurement. Analyze working standards together with samples and reagent blanks (steps 10 through 12) on a spectrophotometer at 730 nm, using a 5-cm cell. Correct standards for reagent blank absorbance. Prepare a calibration graph of absorbance vs. amount (μg) of monomethylhydrazine per sample. ”