Confirm the type and concentration range of the gas to be tested. The type of gas encountered in each production department is different. All possible situations should be considered when selecting a gas detector. For example, in the mining environment of coal mines, methane and less toxic alkanes, it is undoubtedly the most suitable choice for the selection of combustible gas detectors. This is not only because the detection principle of the gas detector is simple, the application is wide, and it has the characteristics of convenient maintenance and calibration.