Safety

Automating internal transport with AGV trucks and autonomous mobile robots AMR is a major step towards higher logistics and manufacturing efficiency. For people and machines to work together safely, however, the whole system has to be built on rigorous and modern standards. The most important one is ISO 3691-4, which replaced the older EN 1525 approach and defines safety requirements for driverless industrial trucks and their systems in a much more precise way.

The standard is built around several core pillars. The first is a comprehensive risk assessment aligned with ISO 12100 and carried out for the specific plant and the specific process. This includes collision points, floor conditions, visibility, personnel presence and realistic traffic scenarios. The outcome of that analysis determines which preventive measures must be designed into the project before the system is allowed to operate.

The second pillar is work-zone management. ISO 3691-4 distinguishes the operating zone, operating hazard zone, restricted zone, confined zone and load transfer area. In practice this means different requirements for clearances, speed limits, signalling and the way each area is protected. Defining those zones correctly allows the rollout team to protect people without sacrificing throughput across the facility.

The third pillar is the reliability of the safety functions themselves. In line with ISO 13849-1, critical functions such as braking, personnel detection and speed monitoring usually need to achieve Performance Level d. In practice this requires redundant safety architectures in which a single component failure does not result in the loss of the protective function or a sudden increase in risk for operators and nearby staff.

ISO 3691-4 also makes it clear that safety is a shared responsibility. The OEM is responsible for delivering a safe machine in its factory state. The system integrator is responsible for implementing that machine safely in the real customer environment, including maps, scanner fields, speed reductions and interaction logic. The end user is responsible for safe day-to-day operation, keeping transport paths clear, training employees and carrying out regular audits and inspections.

In practical terms, investing in a system that complies with ISO 3691-4 means greater reliability, better protection of employee health and a more stable logistics operation around the clock. It is a standard that structures the project from the technical, legal and operational side at the same time, and it shortens the path to a safe rollout in a real industrial environment.