Flash point is a major indicator on the study of fire and explosion hazards of liquid mixtures. Mixtures presenting a minimum flash point behavior are particularly dangerous. It has been shown before that minimum/maximum flash point mixtures could be related with azeotropic behavior under some conditions. Since the 70's a classification of ternary azeotropic mixtures has been developed based on the topological properties of residue curve maps arising from the simple evaporation equilibrium model. In this paper we show that such a general classification also exists for flash point diagram of miscible flammable compound ternary mixtures and that it could help anticipate fire and explosion hazard in ternary mixtures. The demonstration is based on the construction of an auxiliary theoretical system under equilibrium equivalent to a non-equilibrium flash point system.