Heat Resistant Chemical Fume Hood Fireproof Damp Proof

Acid & Alkali Resistant Heat Resistant Fireproof Explosion Proof Chemical Laboratory Fume Hood

1. Product Description

A fume hood (sometimes called a fume cupboard or fume closet) is a type of local ventilation device that is designed to limit exposure to hazardous or toxic fumes, vapors or dusts.

A fume hood is typically a large piece of equipment enclosing five sides of a work area, the bottom of which is most commonly located at a standing work height.

Two main types exist, ducted and recirculating (ductless). The principle is the same for both types: air is drawn in from the front (open) side of the cabinet, and either expelled outside the building or made safe through filtration and fed back into the room. This is used to:

-protect the user from inhaling toxic gases (fume hoods, biosafety cabinets, glove boxes)
-protect the product or experiment (biosafety cabinets, glove boxes)
-protect the environment (recirculating fume hoods, certain biosafety cabinets, and any other type when fitted with appropriate filters in the exhaust airstream)

Secondary functions of these devices may include explosion protection, spill containment, and other functions necessary to the work being done within the device.

2. Product Parameters

3. More About the Fume Hood

A ducted fume hood relies on the facility's ventilation system for venting exhaust air outdoors using ducts. The fan or blower is typically located on the roof of the building, allowing for quiet operation of the fume hood. To prevent recirculation of contaminated air, the ductwork for a fume hood should be separated from the rest of the facility's ventilation ducts.

A ductless fume hood, also called a recirculating fume hood, uses a blower on the fume hood to pull contaminated air through a HEPA filter, and then recirculates the air back into the room. The type of filter required varies depending on the chemistry, so the operator must ensure use of the proper filter for safety. Filters also must be changed regularly for safety.

The sash on a fume hood serves many purposes, but the most important one is to protect persons working in the laboratory. When the sash is closed it prevents any "leakage" of chemical fumes from the hood.

A closed sash also protects you from "escapes" caused by accidents. Shattered glass, chemical spills, and vapors are contained in the hood if the sash is closed and an "event" occurs.

Closing the sash improves overall hood performance for other hoods in the lab and within the building. Also, in case of a power outage or hood ventilation failure, chemical vapors will not back up into the laboratory. Closing the Sash for Safety is a very healthy habit to develop.

4. Detailed Photos

5. Fume Hood Maintenance

• Hoods should be evaluated by the user before each use to ensure adequate face velocities and the absence of excessive turbulence.

• In case of exhaust system failure while using a hood, shut off all services and accessories and lower the sash completely. Leave the area immediately.

• Fume hoods should be certified, at least annually, to ensure they are operating safely. Typical tests include face velocity measurements, smoke tests and tracer gas containment. Tracer gas containment tests are especially crucial, as studies have shown that face velocity is not a good predictor of fume hood leakage.

• Laboratory fume hoods are one of the most important used and abused hazard control devices. We should understand that the combined use of safety glasses, protective gloves, laboratory smocks, good safety practices, and laboratory fume hoods are very important elements in protecting us from a potentially hazardous exposure.

• Laboratory fume hoods only protect users when they are used properly and are working correctly. A fume hood is designed to protect the user and room occupants from exposure to vapors, aerosols, toxic materials, odorous, and other harmful substances. A secondary purpose is to serve as a protective shield when working with potentially explosive or highly reactive materials. This is accomplished by lowering the hood sash.

6. Project Cases