The phenomenon of coal spontaneous combustion is one of the common hazards in coal mines and also one of the important reasons for the loss of coal in piles and mines.Based on previous researches,different types of coals have different spontaneous combustion characteristics.For coal loss prevention,a measure is necessary for prediction of coal spontaneous combustion.In this study,a new engineering classification system called "Coal Spontaneous Combustion Potential Index (CSCPI)" is presented based on the Fuzzy Delphi Analytic Hierarchy Process (FDAHP) approach.CSCPI classifies coals based on their spontaneous combustion capability.After recognition of the roles of the effective parameters influencing the initiation of a spontaneous combustion,a series of intrinsic,geological,and mining characteristics of coal seams are investigated.Then,the main stages of the implementation of the FDAHP method are studied and the weight of each parameter involved is calculated.A classification list of each parameter is formed,the CSCPI system is described,and the engineering classifying system is subsequently presented.In the CSCPI system,each coal seam can be rated by a number from 0 to 100;a higher number implies a greater ease for the coal spontaneous combustion capability.Based on the CSCPI system,the propensity of spontaneous combustion of coal can be classified into three potential levels:low,medium,and high.Finally,using the events of coal spontaneous combustion occurring in one of the Iranian coal mines,Easte Alborz Coal Mines,an initial validation of the mentioned systematic approach is conducted.Comparison of the results obtained in this study illustrate a relatively good agreement.