RISERS More precisely known as return air risers, which are used to collect the return air in a specific manner to maintain a perfect laminar flow. APPLICATIONS They find a wide application in Pharmaceuticals and clean room industry where proper class of cleanliness is to be maintained. CONSTRUCTION Return air risers are manufactured in the factory as per the design requirement. ADDITIONAL FEATURES LIKE Prefilters alongwith front removable / accessible door can be provided as per requirement.(Any other accessories as per requirement can be provided.)