Chemical Fume Hoods provide users with the ability to safely work with substances that, otherwise, may prove harmful or even fatal. Many of the advanced technologies and discoveries we enjoy today would not be possible without them. Each hood must be in proper working order to ensure long healthy lives for laboratory personnel.


How can we be certain that our hood is providing proper containment? The best way to know that an individual hood is doing its’ job is to have it evaluated using the ASHRAE 110-1995 Method. This is a quantitative test utilizing tracer gas to measure a hoods containment ability in parts per million (ppm).

The 2003 update to “The American National Standard for Laboratory Ventilation” mandates this test procedure for all new and remodeled fume hoods (ANSI/AIHA Z9.5-2003). The ASHRAE 110 - 1995 test is now required based upon empirical evidence showing a large percentage (17%) of hoods pass the face velocity test but failing the tracer gas portion (ANSI AIHA Z9.5 pg. 16). We recommend every hood be baseline tested and, where applicable, corrections made until the hood meets acceptable performance levels. In subsequent years a less rigorous procedure (i.e. LTMW 0112 SOP) can be employed to demonstrate that, all factors being equal, the hood is providing the same level of protection.

ANSI/ASHRAE 110 - 1995
Required as a Baseline Test
Annual Testing - "Less Rigorous"