National Institute for Occupational Safety and Health

“ Breakthrough tests were conducted with a generated test atmosphere at 1.9 ppm with four impregnated charcoal tubes. The sample volume was 120 L. The average collection efficiency in the front sections was 99.8 ± 0.3%. Breakthrough occurred in only two samples indicating 0.6 and 0.2% breakthrough. An additional breakthrough study was conducted with a generated test atmosphere containing 0.34 ppm diborane at a relative humidity of 60 to 70%. ”

“ The results indicated that the use of the PTFE filters does not affect the precision or accuracy of the method. Mixed cellulose ester membrane prefilters produced a loss of 7.5% in the collection efficiency and, therefore, are not recommended as prefilters. ”

“ Personal sampling pump, 0.5 to 1 L/min, with flexible connecting tubing. 3. Plasma emission spectrometer with a DC plasmaexcitation source. 4. Pipets, plastic, 10-mL, and 5- to 50-μL. 5. Volumetric flasks, plastic, 10-mL. 6. Bottles, screw-top, plastic, 60-mL. 7. Syringe, plastic, 10-mL, fitted with 0.5-μm PTFE filter. 8. Vials, plastic, 7-mL, screw-on septum caps. 9. Ultrasonic bath. 10. Gas-tight syringes, 0.5- and 5-mL, graduated.
SPECIAL PRECAUTIONS: Diborane is very toxic and flammable, having an Immediately Dangerous to Life or Health (IDLH) level of 40 ppm. ”