(under subclass 437) Subject matter wherein there is a gas which includes entrained solid particles of dust or smoke.
(1) Note. Both visual and photoelectric detection devices of the static and the flowing type are here.
(2) Note. For light transmission tests involving chemical concentration of gases which do not contain particulate material, see the colorimeters in subclasses 402+ above.
(3) Note. This subclass only provides for testing the transmission characteristic of a gas with particles of dust or smoke uniformly distributed therethrough. For testing the transmission characteristic of gases, per se, see subclasses 402+ where color is involved, or subclass 437 above.
(4) Note. Included are the apparatus to determine the particle count in gases by means of light transmitted through the particle-containing gas.
SEE OR SEARCH THIS CLASS, SUBCLASS:
36+, for the preparation of sample gases which may include entrained moisture and/or particles such as "condensation nuclei". 246, for fluid containers, per se.
337+, for the detection of light scattered by the entrained particles or moisture in a flowing or static gas.
