Abstract: A method of determining whether a structure such as a bridge has been severely damaged by an earthquake or other disturbance such as a flood. The method is designed to be carried out by unsophisticated persons immediately after such disturbance so that unnecessary delays will not be caused by the closing of bridges and the like which are not severely damaged. The method involves affixing a target to one portion of the structural member such as a span and affixing a pointer on another structural member such as a column. Preferably the target and pointer are positioned in such a way that a safe or unsafe determination can be easily made by the viewer.