04207883 is referenced by 10 patents and cites 16 patents.

An environmental control hood assembly includes a headpiece and a noise filter subassembly which is disposed within the headpiece adjacent its top wall. The filter subassembly includes a silencer member with an air-permeable wall portion and is connected to the conduit which in turn is connected to the source of air under pressure. The silencer member in turn is disposed within a foam member which is fabricated of an air-permeable synthetic resin open cell foam so that air introduced into the silencer member must travel a path through the silencer member and through the foam with resultant reduction in the sound level of that air. A barrier may be provided under the silencer to preclude direct flow of air from the silencer downwardly through the foam, and the filter subassembly may include a bottom sheet of an air-pervious material.

Title
Hood assembly with noise filter
Application Number
5/924654
Publication Number
4207883
Application Date
July 14, 1978
Publication Date
June 17, 1980
Inventor
Harry A Shindler
West Hartford
CT, US
Assignee
Nuclear & Environmental Protection
CT, US
IPC
A62B 17/04
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