04739755 is referenced by 206 patents and cites 5 patents.

The device relates to a mask worn over a wearer's face for air filtration. The mask has an inturned lip that forms a seal on the edge of the mask with the wearer's face. The mask also has at least two other contact surfaces, internal to the edge seal, which vary in length to increase the seal integrity of the mask. The mask has an exhalation valve in the front in direct line of expelled breath and a plurality of horizontal pleats below the exhalation valve such that the wearer can talk without substantial movement of the sealing edge. The mask also has two inhalation valves on each side, over the cheeks, to allow air to enter the mask.

Title
Respirator
Application Number
6/920570
Publication Number
4739755
Application Date
October 17, 1986
Publication Date
April 26, 1988
Inventor
Jay A Parker
Flushing
NY, US
Kevin D Rodgers Sr
Medford
NY, US
Willard C White
Huntington
NY, US
Agent
Gordon L Hart
Assignee
American Cyanamid Company
CT, US
IPC
A62B 7/00
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