Absolute ventilation efficiency

Absolute ventilation efficiency A value that provides a means of determining the actual ability of a ventilating system to reduce the concentration of a pollutant, compared to that theoretically possible. 

Caution. Chromium(VI) oxide, Cr03, is carcinogenic. Especially after the drying procedure, inhalation of the fine powder must be avoided by working in a well-ventilated hood. Also the use of the toxic CO gas makes an efficient hood absolutely necessary. The final Cr(II) catalyst is extremely pyrophoric and should never be allowed to get into contact with air. 

SPILL CLEAN-UP ventilate area of spill or release collect powdered material in a cautious manner and deposit in sealed containers use a vacuum or a wet method to reduce dust during clean-up avoid cleaning by dry-sweeping a high efficiency particulate absolute (HEPA) filter should be used when vacuuming, not a standard shop vacuum employees must be properly trained and equipped to clean-up spills OSHA 1910.120 (q) may be applicable. 

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