Fume hoods, or fume cupboards, work to ensure the safety of lab personnel while working with hazardous materials by continuously delivering airflow away from the user. When used properly, fume hoods can prevent users and the environment from toxic gases, explosions, and spills.
Fume hoods have proper ventilation
Breathing in harmful chemicals can cause toxins to lodge in your lungs or enter the bloodstream. While inhaling vapors may only result in dizziness at first, over several years it can cause liver damage. By design, a fume hood provides a barrier between lab workers and toxic fumes by filtering the air inside the laboratory.
Fume hoods can either be ducted or ductless.
Ducted fume hoods remove the air from the laboratory and disperse it into the atmosphere outside. While many ducted hoods employ constant air volume (CAV) systems, variable air volume (VAV) systems are a new generation of hoods that reduce energy costs. VAV systems reduce the volume of the air exhausted as the fume hood sash is closed.
Ductless fume hoods recirculate the air by filtering it before redistributing it back into the laboratory. Different filters are required for different materials, so ductless hoods should only be used when the material is known and doesn’t change.
Fume hoods are designed for explosions
While they aren’t designed to handle every incident, a properly-installed fume hood will provide protection from small explosions and fires.
The sash acts as a shield in the case of an explosion or fire. It is designed to withstand impact, so in the case of an explosion, the glass will “spider” instead of shatter.
The sash should always be shut when the hood is not in use. If an explosion occurs when the sash is open, the glass and contents inside the hood will be spread around the laboratory, potentially harming other lab personnel.
Fume hoods control and contain spills
Spill containment lips help to contain minor liquid spills. These lips are several inches wide and act as catch basins for spills or breaks.
These “troughs” are the new standard for fume hoods, but most older hoods don’t come with this feature. However, additional spill containment products can be purchased for older hoods.
Although fume hoods are essential, they cannot protect against every laboratory hazard. Extremely dangerous work will require specifically-designed equipment. Regardless, fume hoods are an indispensable piece of equipment.