Abstract:

This work addresses selected aspects of human factors in designing the instrumentation and control (I&C) systems important to safety as a part of the functional safety management of industrial hazardous plants, in particular nuclear power plants. As it is known in such plants a concept of “defence in depth” (D-in-D) is widely applied and some layers of protection are designed with regard to functional safety (FS) concept given in the international standards: IEC 61508 (FS generic standard), IEC 61511 (FS in process industry sector) and IEC61513 (FS in nuclear power plants). These standards indicate generally the importance of human factors, as the human-operators can contribute significantly to performing of safety functions, however, there is no detailed guidelines how to deal with such issues. The aim of research undertaken and outlined in this article is to develop methodology for supporting the design of I&C systems important to safety that might include evaluation of human factors and human reliability analysis (HRA). It is of prime importance for correct verification of the safety integrity level (SIL) of defined safety functions being implemented using the I&C systems.