Polish school of reliability and safety

The history beginning of School of Safety and Reliability in Poland is represented in paper. Authors of the School are among other Prof. Krystyna Ważyńska-Fiok, Prof. Jerzy Jazwiński, Prof. Jan Borgoń, Prof. Zbigniew Smalko, Prof. Józef Żurek, Dr. Tadeusz Salamonowicz, Prof. Tadeusz Szopa, Prof. Alfred Brandowski, Dr. Krzysztof Kolowrocki. Among scientific institutions having greatest contributions in development of the Polish School of Safety and the Reliability are Committee of Transport and Committee of Machines Construction of Polish Academy of Sciences, Air Force Institute of Technology, Faculty of Transport of Warsaw University of Technology, Polish Cybernetic Society, Polish Society of Safety and Reliability. Conferences "Problems of the Reliability in the Transport" and "Safety of Systems" "International Conference of Safety and Reliability KONBIN" determine leading in the country and recognized in the world meeting points scientist occupying with these scientific problems. The reliability and the safety are with themselves related. The elements the three-stage, renewable three-stage element, the fourth state of security threat, the fifth state of feeling security threat are an object of the paper. Markov processes and the theory tracing systems of the safety are presented in paper. The three-stage object non-renewable, the model of the object of damages, the diagram presenting time of flight, the elementary model system, "the system protected - the system switching on - the system protecting", the object of the structure ranker complex of three-stage elements the model of the three-stage renewable object with reversible state of efficiency deceptive, the reduced model, the three-stage renewable object are discussed in the paper.