Abstract: A safety network for supporting mobile robots in a facility including: one or more zone safety controllers each operating a zone safety loop responsible for a predefined zone of the facility, including monitoring zone safety sensors and taking actions in response to detected safety events with effect in the zone only; a fleet management system configured to perform mobile robot route planning and repeatedly associate each of the one or more mobile robots with a responsible zone safety controller; and wherein each zone safety loop exchanges safety event messages with an onboard safety loop in each mobile robot, for which the zone safety controller is responsible.