Fume hoods reduce exposure to fumes that may be toxic or hazardous. Used for lab safety, they protect lab workers as well as the lab environment. From general purpose hoods, vented enclosures, ducted fume hoods, biosafety and PCR enclosures, and extractor systems, choosing the correct fume hood is a matter of narrowing down your choices to the match that is ideal for your application.
Choosing a Fume Hood
When choosing a fume hood, start by determining if you are protecting products, staff, or both. If you are protecting products, you’ll need a vertical or horizontal clean bench or a PCR enclosure. If you are protecting personnel and a chemical will be used, a ducted or ductless chemical hood or a fume extractor will be required. If using powders, a vented enclosure or fume extractor is required. If using biologicals, a Class 1 biosafety cabinet is needed. When protecting products and staff members, a Class II biosafety cabinet is required.
Biosafety and PCR Enclosures: Hybrid models enable handling of sensitive materials while protecting the user. Airflow is HEPA filtered entering the cabinet and again upon exit, or discharged to the outside. Applications include manipulating dangerous but sensitive biological materials, e.g. Class II, Type A2 cabinets
Ducted Fume Hoods: Ventilation to the outside provides the most rigorous user protection, particularly for chemically dangerous fumes. Many employ “by-pass” designs, which enable consistent airflows in the enclosure for various sash positions. Low airflow designs provide user protection while minimizing energy costs.
Ductless Fume Hoods: These enclosures pass contaminated air through a filter(s) before returning air to the room. They are used for locations where outside ventilation is not possible. They can eliminate very high percentages of particulates and biological hazards. Select airborne chemical levels can be reduced to safe levels as verified with monitoring protocols.
Vented Enclosures: These hoods enhance fume removal by partially surrounding the fume source. Some models direct forced airflow to afford further protection. Low-flow ventilation systems enable delicate operations, e.g. weighing while maintaining personal protection.
They may vent to the outside or recirculate into the room via a filter.
Extractor Systems: Provide localized ventilation at the contaminant source. Extractor arms can be easily positioned to remove fumes or airborne particulates. Often used when the fume source cannot be readily moved to a conventional hood or when fumes are innocuous, e.g. bad-smelling without being chemically dangerous. The systems may vent to the outside or recirculate into the room through a filter.
View all types of fume hoods.