G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
G01N33/0004—Gaseous mixtures, e.g. polluted air
G01N33/0009—General constructional details of gas analysers, e.g. portable test equipment
G01N33/0027—General constructional details of gas analysers, e.g. portable test equipment concerning the detector
G01N33/0036—General constructional details of gas analysers, e.g. portable test equipment concerning the detector specially adapted to detect a particular component