AGV safety should never be reduced to sensors and emergency stops alone. ISO 3691-4 becomes useful only when it is linked to the actual traffic model, site layout, interaction points and mixed-traffic scenarios of a given plant or warehouse.
That is why real deployments require more than a compliance declaration. They require decisions about speed profiles, risk zones, operator behavior and the way automated vehicles coexist with manual transport.
The main lesson is simple: the standard is the framework, but safety performance depends on how well the project team translates it into the real environment.
