Abstract: A heater for heating dionized water and other liquids which may be very aggressive solvents, the heater constituting one or more heating units having an external cylindrical housing of PTF Teflon or similar material and closed at each end with headers of similar material which contain ports for ingress and egress of the fluid. A concentric inner tubular member of polysilicon surrounds one or more infra red heating elements which, when energized, radiate intense heat into the chamber within the inner tube. This tube acts to confine and reflect the heat back into the chamber thereby heating the liquid to a high temperature very quickly. Relatively little heat passes through the wall of the inner tube to the surrounding chamber. Liquid is directed into the outer chamber, across the length of the inner tube, through a passage at the opposite end and into the inside chamber. The flow across the other surface of the inner tube is warmed somewhat but insufficiently to damage the outer tube.

Abstract: A ceiling system for clean rooms is disclosed employing two sets of framed filters, an upper set and a lower set arranged in checkerboard fashion. One set supports the other set and the supporting set is suspended from the overhead or ceiling of the room. A plenum of two height levels is formed. The upper set has depending skirts below the level of its filter medium. The lower set of framed filters include an outer lip or rim which seal the filter sets together at the depending skirts of the upper set. Auxiliary services such as lighting and sprinklers are fed from above the sets of framed filters via the depending skirts of the upper set. In one embodiment, the upper set of framed filters supports the lower set and in an alternate embodiment, the lower set of framed filters supports the upper set. Grid or T bar support systems are eliminated and nearly 100 % filtered laminar flow area is produced.