National Institute for Occupational Safety and Health

“ Place a filter spacer ring in the bottom section of a two part 37-m m filter cassette. Place a 37-m m quartz fiber filter on top of the spacer ring (do not use a s upport pad) . b. Inoc ulate the filter with a known amount of calibration stock solution with a microliter syringe, place the top section of the cassette in place and seal the filter in place by squeezing the two sections together. c. Place the plugs in the inlet and outlet tubing stubs and set the cassettes aside for a minimum of twelve hours. d. Prepare the filter samples (steps 4 & 5) and analyze with the calibration standards. ”

“ Rotate the samples for a m inim um of 2 h ours . Place sam ples in an ultrasonic ba th for 3 0 m inutes . NOTE: Decabrom odiphenyl oxide is not a highly soluble com pound. T o insure com plete s olubility, both m anual agitation and sonication are used on the samples to solubilize the decabromodiphenyl oxide. 5. Prepare the filter extract for analysis. a. Carefully remove the septum cap from the vial containing the extracted filter. ”

“ The LO D/LO Q values are 1.0 μg/sa m ple and 3.3 μ g/s am ple res pectively, based on a liquid standard calibration curve. Reco very of spiked quartz fiber filters rang ed from 94.5% to 104.2% for an alyte quantities of 2.6 3 to 25.1 μg/filter using liquid standa rds as the sp iking solution. A thirty day storage stability study of DBDPO spiked on quartz fiber filters indicates that the recovery of the ana lyte at a level of 5.01 :g/filter (N=12) is 103.0%. The sam ples were stored in a closed cardboa rd container at roo m tem pera ture fo r the duration of the study. ”