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PCE
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DIFF Subgroup
G01N 21/81

Indicating humidity

Introduced: January 1980

Full Title

Full titles differ between systems:

IPC:

Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light > Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated > by observing the effect on a chemical indicator > producing a change of colour > Indicating humidity

CPC:

Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light (G01N3/00 - G01N19/00 take precedence) > Systems in which material is subjected to a chemical reaction, the progress or the result of the reaction being investigated (systems in which material is burnt in a flame or plasma G01N21/72, G01N21/73) > by observing the effect on a chemical indicator > producing a change of colour > Indicating humidity

No child classifications to compare. This is a leaf node in both IPC and CPC.