Many people are asking me what gases are detected by the sensors. All I can do is quote the Figaro Sensors documentations:
“The TGS 2602 has high sensitivity to low concentrations of odorous gases such as ammonia and H2S generated from waste materials in ofﬁce and home environments. The sensor also has high sensitivity to low concentrations of VOCs such as toluene emitted from wood ﬁnishing and construction products.”
“The TGS 2600 has high sensitivity to low concentrations of gaseous air contaminants such as hydrogen and carbon monoxide which exist in cigarette smoke. The sensor can detect hydrogen at a level of several ppm.”
The data sheets do not say much more. In particular, I do not know if the sensors are sensitive to other types of gases, what the exact list is, and how they react to a mixture of gases.