Fume Hood

Fume hoods are a type of ventilation system used in many laboratories throughout the University. Their primary function is to exhaust chemical fumes, vapors, gases, dust, mists, and aerosols.
They also serve as physical barriers between reactions and the laboratory environment, offering a measure of protection against inhalation exposure, chemical spills, runaway reactions, and fires.
A typical fume hood has a box-like structure with a moveable sash window. Experimental procedures are performed within the hood which is consistently and safely ventilated, usually by means of an extract blower and ductwork.

Chemical fumes are exhausted and diluted many times over in the atmosphere and have an insignificant effect on human health. Fume hoods function by maintaining a relatively negative interior pressure while continuously drawing air through the sash opening, which prevents contaminants from escaping. A suitable hood face velocity (the speed at which air is drawn into the hood) is critical to safe and effective operation. While excessive face velocities can result in turbulence and reduce containment, insufficient velocities also compromise performance. On educational versions, the sides and sometimes the back of the unit is also glass, so that several pupils can look into a fume hood at once.