This part of EN45545 specifies the reaction to fire performance requirements for materials and products used on railway vehicles as defined in EN45545‑1 . The operation and design categories defined in EN45545‑1 are used to establish hazard levels that are used as the basis of a classification system. For each hazard level, this part specifies the test methods, test conditions and reaction to fire performance requirements. It is not within the scope of this European Standard to describe measures that ensure the preservation of the vehicles in the event of a fire.