A fume hood
, also called a fume cupboard
, or colloquially just a "hood," is a critical piece of safety equipment in any chemistry
laboratory, designed to ensure proper ventilation of hazardous fumes. The fume hood is generally a large working area in which chemical reagents can be placed. A constant air flow is created through the device, usually using fans, exhausting air through the top of the fume hood and out of the building. If the hood is working properly, most or all of the vapors from any chemical reagents placed in the hood will be exhausted from the laboratory area, thus reducing the health risk to the laboratory technicians.
To determine whether a chemical is likely to require a fume hood for safe usage, its material safety data sheet (MSDS) should be consulted. If there is doubt, use a hood.