RELIABILITY ACCOUNTING IN SYSTEM SAFETY ASSESSMENT

Abstract

The work considers possibility of assessing the complex technical systems safety according to their reliability characteristics. Reliability and the system security are two defining assessments of the system quality, but they characterize it in different ways. Reliability characterizes it in terms of its ability to perform its functions under given conditions. At the same time, security is the possibility of existence or integrity of both the system, and the people, and the environment around it. However, they are logically connected – factors that lead to unreliability can be the cause of dangerous situations. Considering that the issue of assessment reliability has been developed in sufficient detail and is widely used, while safety assessment has not been sufficiently developed due to its complexity and problematic nature, the use of additional information would allow to some extent reveal partially this problem. Taking into account the fact that the issue of reliability assessment is carried out during the design or operation of systems, and the assessment of other parameters will not be too difficult, such an assessment of safety can be considered, to a certain extent, real. In addition, an emergency situation can occur with a combination of certain unfavorable conditions, in which the failure of the system can weaken it or provoke certain destructive processes that can lead to an emergency situation. For example, the loss of the ship's speed or the failure of the car's brakes. Therefore, the proposed security assessment can be used for systems for which a failure may lead to a critical situation under certain conditions. In such cases, even at the design stage, they try to increase the reliability of the system or its stability in adverse conditions or constructively form the protection of the system against possible destructive changes. The introduction of system protection systems against destructive changes provides an opportunity to reduce them or even prevent such changes, protect people and the environment from the negative impact of accidents. The proposed method can be used to assess safety and develop measures to increase it, as well as to create systems to protect the system itself, people and the environment.