BRAND NEW Ductless Fume HOOD 3FT WIDE. FULL FACTORY WARRANTY (parts and labor) The PURAIR 5 is a compact ductless fume hood with Carbon filter that is efficient and economical but offers many features offered in more expensive systems. Introduction The PURAIR 5 range of hoods give the operator safety where routine work is being carried out. The units operate at low noise levels and because they recirculate they do not exhaust expensive conditioned and/or heated air into the atmosphere. A face velocity at 100 fpm ensures containment of vapors and an alarm will alert the operator when the airflow falls to an unacceptable level. The PURAIR 5 unit is a compact bench mounted unit.