Safety

The standard describes FMEA and Failure Mode, Effects and Criticality Analysis (FMECA), and gives guidance as to how they may be applied to achieve various objectives by providing the procedural steps necessary to perform an analysis; identifying appropriate terms, assumptions, criticality measures, failure modes; defining basic principles; and providing examples of necessary worksheets or other tabular forms. All the general qualitative considerations presented for FMEA will apply to FMECA, as latter is an extension of the other.

This International Standard describes fault tree analysis and provides guidance on its
application as follows:
definition of basic principles;
describing and explaining the associated mathematical modelling;
explaining the relationships of FTA to other reliability modelling techniques;

description of the steps involved in performing the FTA;
identification of appropriate assumptions, events and failure modes;
identification and description of commonly used symbols.

The standard is intended to be a basic functional safety standard applicable to all kinds of industry. It defines functional safety as: “part of the overall safety relating to the equipment under control (EUC) and the EUC control system which depends on the correct functioning of the E/E/PE safety-related systems, other technology safety-related systems and external risk reduction facilities.”