Gas detectors are available for a specific type of gas, but also as a combination device for the detection of different types of gas. There are detectors to detect increased CO or CO2 concentrations, for liquefied petroleum gas (propane, butane), natural gas (methane), but also for anesthetic gas (knockout gas), e.g. in the event that burglars should use appropriate gas. However, it should be noted that the combination devices can almost never measure different gases at the same time, as the weight ratio of the different gases in relation to air is different: a detector for LPG should be installed close to the ground, as it is heavier than air, whereas natural gas is lighter than air, so the corresponding detector should therefore be mounted near the ceiling. The anesthetic gas concentration, on the other hand, should be monitored at head height of the sleeper. Before installation, it must therefore be decided which gas is to be primarily monitored.
Source: bauwion
