What Is A Fume Hood?

Oct 28, 2018 10:00:00 AM / by Albert Cappello

Laboratories use a wide variety of chemicals, some of which can be toxic and/or volatile. Because of this, protecting lab employees and students is extremely important.

So, how do you do that?

One of the best ways to do that is through the use of a fume hood


What Is A Fume Hood?


A fume hood is basically an enclosed industrial workbench with an exhaust system that is designed to limit the person doing work on the workbench from exposure to hazardous or toxic fumes, vapors or dusts. It has an enclosure on three sides, with the fourth side open for the lab worker to operate.

Fume hoods have a fan that creates a positive airflow to pull contaminants into the filtration system. The major difference in fume hood design occurs in the manner used for venting the contaminated air.


Types Of Fume Hoods


There are two types of fume hoods...Ducted and ductless. The major difference between the two is the method through which the fumes are vented away from the worker.

Ducted Fume Hoods 

what is a fume hoodDucted fume hoods handle a variety of chemicals. Fumes from procedures are safely vented outside using ductwork, so there is little or no danger of contamination in the lab.

Because they have ductwork that is attached to the building, ducted fume hoods are stationery with a fixed position in the lab. This ensures that there is always adequate egress from the lab in case of fire or chemical dispersion. 

Ducted fume hoods are usually manufactured in standard sizes, however a quality manufacturer can usually make a custom size that works best in your lab layout.

If you need to connect your fume hood to gas lines, ducted fume hoods often have the connections built in, so you can plumb them directly to the gas lines. This reduces the risk of improper or incorrect connections, helping to ensure the safety of your lab procedures and personnel.

Ducted fume hoods can  be manufactured to include sinks and electrical outlets.  You can also get a variety of countertop options that can stand up to any range of chemicals or temperatures.

You can read more about which countertop is best for your application in our article, Top 5 Materials To Consider For Your Lab Countertops.

Ductless Fume Hoods

what is a fume hoodDuctless fume hoods operate off a carbon filter system that recirculates filtered air into your building. Ductless hoods are often referred to as re-circulating range hoods.  They filter the air and then return the clean air back into the workspace.

Ductless fume hoods are great for use in existing buildings where the ductwork is inaccessible, where mobility is necessary or cost is an issue. 

They are also a good choice in a lab that only does procedures intermittently, or that does procedures that require only a few chemicals.

It is less expensive to purchase and install a ductless fume hood, because they do not require permanent attachment of ductwork to the building. Because ductless fume hoods run only when in use, they may be more cost effective. Although, the initial cost advantages may be outweighed over time by the cost of replacement filters.

To learn more about the benefits of ductless fume hoods, check out our recent blog on the topic.




Fume hoods are an important piece of equipment for any laboratory environment. When used properly, they help protect lab employees and students working with toxic or volatile chemicals and compounds.

Regardless of whether you are leaning toward a ducted or ductless fume hood, fume hood safety should be your first consideration. Be sure the fume hood you are considering is rated for the temperature, volume and chemicals you will use.


fume hood safety

Albert Cappello

Written by Albert Cappello

Albert Cappello is the CEO of Workstation Industries, Inc. WSI is a manufacturer of Industrial, Technical and Laboratory Furniture based in Southern California.

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