Fume Hood Design. A chemical fume hood is a ventilated enclosure used to trap and exhaust vapors, gases, and nanoparticles. The exhaust fan is typically stationed at the top of the building and pulls air through the duct work connected to the hood and exhausts it into the atmosphere.

Fume hoods should be used when working with toxic compounds or compounds with a boiling point below 120°C. Fume hoods, or other effective local ventilation, must be provided and used when the materials used will exceed exposure limits in the laboratory.