Compliance is typically demonstrated via and certification (especially for SIL 2–4). This includes audits of the safety lifecycle, hardware metrics, and software development processes.
Recognizing this gap, the International Electrotechnical Commission (IEC) began work on a generic , technology-independent standard. The first edition of IEC 61508 was published in 1998. It was revolutionary because it moved from prescriptive rules to performance-based metrics. iec 61508 functional safety standard