Huge amounts of hazardous materials are transported by rail and road, being from time to time involved in traffic accidents. In these cases, flammable materials such as, for example, LPG, can originate a severe accident if a loss of containment takes place: a BLEVE explosion usually followed by a fireball. This type of accident, which often follows the domino effect sequence of fire¿explosion, has caused the death of many people, including firefighters and spectators, the mechanical and thermal effects reaching significant distances. A historical survey has been performed on 167 accidents obtained from diverse databases. The results thus obtained have been used, together with the adequate mathematical models, to analyze the time to failure that can be expected and to estimate the lethality reach of the diverse effects-overpressure, ejected fragments, thermal radiation. Finally, a set of considerations concerning the safety and emergency measures that should be adopted in these accidents are commented