A single chemical fume hood can use as much energy as 3.5 households daily due to the large volume of air that must be moved through the hood by the ventilation system. 

Fume hoods can either be of :  

• Constant Air Volume (CAV): the amount of air flowing through the hood is constant

• Variable Air Volume (VAV): the amount of air flowing through the hood can be adjusted

Since energy consumption in fume hoods is related to the volume of air flowing, reducing the airflow volume in a VAV fume hood results in energy savings.

How to save energy?

• Keep a minimum of items under the hood so that the airflow can work as efficiently as possible.

• Remember to adjust the height of your VAV movable sash to minimise the airflow and the speed of the exhaust fan while you are working.

• Close the movable sash when you are done. The energy savings from lowering the sash in a VAV fume hood can be upwards of 40%.