Abstract: An air filtering system of the type used in clean rooms and the like supportable from a ceiling. The unit includes a supporting frame with an opening therethrough, the supporting frame being suspended from the ceiling by cables or the like. A filter having a filter frame therearound is placed within and across the opening in the support frame. A cutting wire is positioned between the supporting frame and the filter frame around the periphery of the opening. One end of the wire is free and extends below the two frames. The other end is fixedly secured to either the filter or support frame. A cuttable seal is applied between the filter and support frames around the periphery of the opening. Clips are also provided to hold the filter within the opening. When one wishes to remove the filter, the free end of the cutting wire is pulled, cutting the seal around the periphery of the opening, thereby allowing the filter and filter frame to be removed from the support frame opening.

Abstract: A diffuser of the type used in supplying filtered air to a clean work area includes a filter housing within which is supported a filter panel. Gaskets are carried on the upper and lower peripheral surfaces of the panel and an adjustable, resilient clamp operably engages the filter and biases the filter and the upper gasket to form a knife edge seal with a portion of the filter housing. A protective grill assembly is sealingly latched to the housing and also forms a knife seal with the lower gasket on the filter panel. Further, a curtain support member is disclosed which is carried by the grill assembly and seals an isolation curtain airtight to the ceiling.

Abstract: A filter hood device containing a gas treating filter and having a clean gas outlet aperture which is closed by a blank diffuser mounting panel. The blank diffuser mounting panel is adapted to be modified at a jobsite to receive a diffuser which is suitable for the requirements of that jobsite.