The method involves receiving location information by radio and associating them to data concerning danger or abnormal situations to which user can be subjected. The location information is used only upon reception of danger/abnormal situation information. A portable receiver/transmitter (1) can be strapped to the person's (2) back. Information is collected from the NAVSTAR GPS system (9) providing positional information which is relayed via an intermediate RF relay (3) to a base station. The base station has a radio receiver (4), computer (3) and can call for suitable assistance (6). The base station collects the person's location and signals generated by him to indicate the assistance needed.