Ducted fume hoods safely remove vapors from the work area through connection to a remote blower or HVAC system. Noxious or dangerous chemicals are vented outside of the room.
Ductless
Provides the same filtration as ducted model. Ductless fan filter units (FFUs) can be placed in any lab space without consideration of adding ductwork or major utilities. Ductless FFUs cut energy bills by filtering and recirculating heated or cooled air back into the laboratory. This means that unlike ducted FFUs, which constantly send treated air outside the facility, ductless FFUs keep more treated air inside of the facility and reduce the load on the HVAC utilities.