05617849 is referenced by 84 patents and cites 20 patents.

Respirator 10 has a respirator body 11 that is configured to fit over the nose and mouth of a wearer. A thermochromic material 18 is positioned on the respirator body 11 such that the thermochromic material 18 makes thermal contact with the wearer's face when the respirator 10 is worn. The contact causes the thermochromic material 18 to change color to allow the wearer to determine if a proper fit has been established.

Title
Respirator having thermochromic fit-indicating seal
Application Number
8/526909
Publication Number
5617849
Application Date
September 12, 1995
Publication Date
April 8, 1997
Inventor
Leonard W Barrett
Maplewood
MN, US
James E Springett
Hudson
WI, US
Agent
Karl G Hanson
Walter N Kirn
Gary L Griswold
Assignee
Minnesota Mining and Manufacturing Company
MN, US
IPC
A62D 5/00
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