Monitoring ambient air for the presence of methane and hydrogen sulfide (using fixed systems) Measuring in sod or probe holes for early warning of gas hazards Measuring and monitoring O2, CO2, CH4, and H2S in manholes and underground buildings (detector tubes are allowed for CO2) Monitoring explosion hazards at gas hoisting systems Monitoring the gas flow of gas hoisting systems to ensure that the CH4 concentration does not fall below 25% volume and / or the oxygen concentration stays between 3 and 6% volume Monitoring gas collectors for the presence of combustible gases, toxic gases, and oxygen
G750, G333	Methane, hydrogen sulfide, carbon monoxide, carbon Dioxide, oxygen
GMA*, MWG	Methane, nonane (fuel vapors)
	* = see image