FIBER OPTIC METHANE SENSOR FOR MINES

Different types of fiber optic methane sensor, especially for mining a pplication, have been reviewed in this paper. Optical absorption and d ifferential optical absorption techniques for the remote detection of methane gas using low-loss silica fiber have been discussed. Infrared fiber optic, sol-gel and correlation spectroscopy methods have been de scribed in brief. Another noble technique based on attenuation of evan escent field has been enunciated using D-fiber. Merits and demerits of each technique and their suitability to mining industry have been hig hlighted. Optical fiber, being a dielectric, non-metallic and non-spar king is an intrinsically safe medium and is ideally suited to the haza rdous environment present in mines.