Iran Occupational Health

Background and aims: coal mines fire is one of the most important problems in all coal production countries. The purpose of the present study was the risk assessment of fires based on Fault Tree Analysis method in fuzzy environment in the coal mines.

Methods: In this research, according to a review of all the latest, known and credible studies about fires from around the world, many important and effective parameters were identified. Afterwards, the causes of firewere determined using FTA method. In order tocalculate the probability ofbasiceventsandeventually reach therate ofoccurrence ofthe topevent(risk of fire) andregarding this fact thatthe possibility ofachievingpreciselythe basic eventsinthefault tree of this event is difficultandwithuncertainty, so fuzzy logic and fuzzy numbers were used to assign probability weight to basic events. Then the probability of top event was determined using the appropriate equations. The critical Minimal Cut Sets (MCS) were determined using Fussell-Vesely equation.

Results: The results showthatthe probability ofthe risk offirein Eastern Alborz Coal Mines is 39.38%, sothat it is thehighlevels ofrisktostaff involved inthisvital and important industry. The existence of gasandcoal dustin site ofwelding, was identifiedasthe most criticalparameter.

Conclusion: The using offuzzy logicinfault treeanalysis method increaseaccuracyand reduceuncertaintyincalculations. Also it makes the evaluationseasier.