Machine safety standards: designing automation people can trust
Automation puts powerful, fast-moving equipment close to people. Good machine safety makes that safe by design — and a safe machine is also more available, because well-designed safeguards are used every shift instead of being bypassed. The discipline is built on an international standards framework worth understanding before you buy or build.
Start here: risk assessment (ISO 12100)
ISO 12100 is the foundation. It defines how to identify hazards — crushing, cutting, entanglement, electrical, stored energy — estimate the risk of each, and reduce it in a set order: first by inherently safe design, then by safeguarding, then by information for use. Every credible safety design starts with this assessment, done before the machine is built rather than after.
Rating the safety functions: ISO 13849-1 and IEC 62061
Once you know which safety functions you need (for example, “opening this door must stop that motion”), two standards tell you how reliable each function must be:
- ISO 13849-1 expresses required reliability as a Performance Level (PL a–e), based on architecture, component reliability (MTTFd), diagnostic coverage and resistance to common-cause failures.
- IEC 62061 expresses it as a Safety Integrity Level (SIL 1–3), the approach more familiar to process and electrical engineers.
Both lead to the same goal: a safety function whose likelihood of dangerous failure is low enough for the risk it controls.
The application standards that do the real work
- ISO 13855 — how to position guards and sensors based on approach speed, so a light curtain actually stops the machine before a hand reaches the hazard.
- ISO 14119 — design and selection of interlocking devices for guards (and how to avoid defeat).
- ISO 13850 — emergency stop: reachable, reliable, and leading to a safe state.
- ISO 10218 / ISO/TS 15066 — the specific rules for industrial and collaborative robots.
Safety and productivity go together
Safeguards that fit the way people actually work — quick, confident loading and unloading — get used. Awkward ones get bypassed, which is dangerous and defeats the investment. The aim is protection designed around the operator, verified during the machine’s acceptance tests (FAT/SAT), so it protects on day one and every shift after.