The IEC 61508 standard is an essential framework for ensuring the functional safety of critical systems in various sectors. It applies to electrical, electronic, and programmable systems and is based on a rigorous risk-based approach. By assessing the potential dangers these systems may pose to the environment and human life, the standard establishes specific reliability and safety requirements.
For example, in the aerospace industry, aircraft control systems must meet very high safety standards. A failure in-flight, even if rare, could cause major accidents. Therefore, these systems are equipped with redundancies and self-diagnostic mechanisms, ensuring that even if a component fails, passenger safety is not compromised. Such systems are required to limit failures to once every 10 million operating hours, a figure similar to that required for nuclear reactors.
The IEC 61508 standard goes further by defining requirements for critical medical devices, such as pacemakers. Since these devices operate inside the human body, their failure could be fatal. Manufacturers must therefore comply with rigorous testing procedures to ensure safe operation over extended periods. The standard also mandates ongoing audits and quality controls to ensure that each device meets these requirements throughout its lifecycle.
Additionally, to reduce risks below acceptable thresholds, the IEC 61508 standard outlines a set of organizational and technical measures. These measures include preventive maintenance protocols, periodic inspections, and the implementation of redundant systems to minimize the likelihood of failure. This highlights the importance of functional safety across various industrial sectors, from transportation to medical fields.
Finally, IEC 61508, which has evolved since its first edition in 1998, has become a global reference standard. It continues to guide efforts in functional safety across diverse fields, including process control systems and transportation infrastructure.