ABSTRACT
The development of heating in a goaf is generally accompanied by the progressive appearance of haze, sweating of the strata, gob stink or fire stink, sound, smoke and fire. In the initial stage of spontaneous heating, as the moisture is released from coal, the water vapour may come in contact with the cooler ventilating air and thereby condense, making haze like formation. The development of radio sonde type of thermal recording devices, as are being used for meteorological purposes, were considered for use in goaf. Stench capsules are known to be used as a method of warning from overheating of mining equipment, or from an active fire in the area. Remote measurement of temperature by means of infra-red radiometry are being tried now-a-days to detect early heating and locate hot spots in mines. Cumore confirmed early detection of heating from estimation of unsaturated hydrocarbons.
