Ignition of methane-air mixtures by laser-heated small particles.
Dubaniewicz-TH Jr.; Cashdollar-KL; Green-GM; Chaiken-RF
Colloquium on Gas, Vapor, Hybrid and Fuel-Air Explosions, 1998 Sep; 2:218-236
Optical Technologies have progressed rapidly in the past 15 years. One application of laser technology in underground coal mines currently under evaluation is the remote measurement of explosive methane gas. Federal regulations require that atmospheric monitoring systems used in gassy underground mines where permissible equipment is required shall be intrinsically safe. Mine Safety and Health Administration criteria for the evaluation and test of intrinsically safe apparatus and associated apparatus contain no guidance for optoelectronic components such as diode lasers. The National Institute for Occupational Safety and Health is conducting a study to help provide a scientific basis for developing appropriate safety guidelines for optical equipment in underground coal mines. Results of experiments involving ignition of methane-air mixtures by small heated particles are reported. Minimum reserved igniting powers for laser energy delivered by 200, 400 and 800 micrometers core fiber optic cables and directed onto selected targets in methane-air atmospheres were 0.6, 1.1, and 2.2 W respectively. Comparisons to results of other researchers are made.
Mining-industry; Underground-mining; Coal-mining; Mine-safety; Air-monitoring; Lasers
National Institute for Occupational Safety and Health, Pittsburgh Research Laboratory, Pittsburgh, PA 15236
Other Occupational Concerns
Colloquium on Gas, Vapor, Hybrid and Fuel-Air Explosions, Proceedings of the International Symposium on Hazards, Prevention, and Mitigation of Industrial Explosions