04297578 is referenced by 88 patents and cites 5 patents.

An airborne dust monitor. Photosensitive elements detect a predetermined airborne dust level at a test region adjacent the photosensitive elements. The photosensitive elements are housed within a flue which shields the test region from ambient light while it conducts ambient air through the test region. In a preferred embodiment, the flue is formed of generally vertical sidewall members which define an ambient air passage through the test region, air passage outlets positioned above the test region and a baffle generally at the inlet of the air passage for allowing the entry of ambient air to the passage while blocking light from the test region. A test system may be provided by which a member is selectively positionable within the test region. Preferably, the photosensitive detecting elements include a radiant energy source and an element responsive to that radiant energy, most preferably infrared energy, the photosensitive elements being positioned to minimize dust settlement on the acting portions thereof.

Title
Airborne dust monitor
Application Number
6/110601
Publication Number
4297578
Application Date
January 9, 1980
Publication Date
October 27, 1981
Inventor
William R Carter
5021 Wooddale La., Minneapolis, 55424
MN, US
Agent
Schroeder Siegfried Ryan Vidas Steffey & Arrett
IPC
G01N 21/00
G01J 1/00
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