IEC 61508

The international standard IEC 61508 describes the functional safety of electrical, electronic and programmable electronic safety-related systems (E/E/ PES). The standard was published by the International Electrotechnical Commission (IEC) in 1998 and adopted as a European standard( EN) in 2001. It provides a guideline for what is technically feasible and economically reasonable. IEC standard 61508 was superseded by ISO 26262 when it was published.

The IEC standard, which consists of seven parts, can be used to certify industrial systems and describes, among other things, how to develop software according to certain quality standards and safety standards. The first three parts of the standard have normative character, the other four informative. Standard 61508 uses specific terms and definitions and specifies the requirements for a safety system, for which corresponding safety levels( SIL) are identified.

IEC 61508 defines the methods and objectives, compliance with which is a prerequisite for certification of a system. To this end, the standard follows a risk-based approach in order to define the requirements for functional safety and integrity, as well as the detection and handling of errors. The requirement for functional safety of software is mandatory in industrial automation technology, transportation, energy supply and automotive technology.