Safety of water supply in crisis conditions

The paper presents the concept of safety in water distribution systems, which is an important issue connected with its functioning in crisis situations. The research undertaken is directed towards methods of safety assessment relating closely to current world trends, aiming to ensure safety of water supply and use. The paper pays special attention to water consumer safety. Safety levels were assumed on the basis of failure intensity, exposure of water consumers and a number of undesirable event groups. Individual values of the immediate risk index were presented and three categories were distinguished as permissible, tolerable, or unacceptable risk categories, according to presumed action. The risk index can characterize the safety of the functioning of technical systems. The risk index definition is considered as the product of threat ranking. The paper contains the original proposal for a new method of risk analysis and assessment.