Gas Sensors for Underground Mines and Hazardous Areas

Some strata gases that get mixed with underground mine atmosphere are highly poisonous and a few are dangerously flammable. Various gases are also formed in underground mines due to chemical reactions, such as spontaneous heating of coal, etc. Concentration of mine gases found at any time and location may vary due to different factors like diffusion, turbulent dispersion, and leakage in subsurface ventilation systems. Therefore, it is necessary to deploy sensors to monitor and measure toxic and flammable gas concentration levels in subsurface atmosphere for the safety of underground miners as well as mines. Each sensor has its own advantages and limitations. Some sensors are better for sensing toxic gases, whereas others are suitable for combustible gas detection. This chapter presents the principles and applications of different types of gas sensors, procedures for sensor deployment and calibration, as well as interpretation of sensor data.