AiVibeIEC 61508
IEC 61508 is the international basic safety standard for the functional safety of electrical, electronic and programmable electronic (E/E/PE) safety-related systems, defining a risk-based life cycle and four Safety Integrity Levels.
IEC 61508 is published in seven parts covering general requirements, hardware, software, definitions, methods for determining SILs, application guidelines and an overview of techniques and measures. Its overall safety life cycle runs from concept and hazard and risk analysis, through allocation of safety requirements, design, installation and validation, to operation, maintenance, modification and decommissioning. Each safety function is assigned one of four Safety Integrity Levels, SIL 1 to SIL 4, according to the risk reduction it must provide.
As a basic safety publication, IEC 61508 underpins sector standards such as IEC 61511 for process industry safety instrumented systems, IEC 62061 for machinery and ISO 26262 for road vehicles. Manufacturers of sensors, safety PLCs, valves and drives use it directly to develop components certified as suitable for a given SIL, documented in a safety manual.
IEC 61508 addresses both random hardware failures, quantified through failure rates, hardware fault tolerance and safe failure fraction, and systematic failures, controlled through development processes, verification and competence. Compliance requires extensive documentation and an independent functional safety assessment whose rigour increases with the SIL. Applying the standard is specialist work requiring qualified, competent personnel.
Key points
- Basic functional safety standard for E/E/PE safety-related systems
- Published in seven parts
- Defines four Safety Integrity Levels, SIL 1 to SIL 4
- Covers the full safety life cycle, including decommissioning
- Basis for sector standards such as IEC 61511, IEC 62061 and ISO 26262
Where AiVibe comes in
AiVibe designs and manufactures the AiAmbA AI Factory, whose edge devices and AI agents let people talk to PLC, CNC and robot controllers in plain language. Agents only propose changes, a trained operator confirms each one, and the AI Factory never replaces a machine's control or safety systems.