Standards of performance for ventilation hoods are set forth by ANSI/AIHA Z9.5 and OSHA 29 CFR 1910.145(e)(3)(iii). The average face velocity of optimally performing hoods should be between 80 and 120 feet per minute (FPM) when measured with the sash raised to the 18" mark. These average face velocities and the date of survey will appear on the inspection sticker located on the front of the ventilation hood.
List of ratings applied to vetilation hoods.
|Pass||Average face velocity 80-120 fpm||Normal chemical hood use|
|Restrict||Average face velocity 70-79 or 121-150 fpm||Not recommended for use with highly toxic materials|
|Fail||Not meeting the above standards||Storage only|