In the defence zones, the zone prefect has access to the resources of all the regional health agencies in the defence zone in order to exercise his powers. Their services are placed under his authority for use when an event involving a health risk may constitute a disturbance to public order within the zone.
The director general of the regional health agency for the capital of the zone assists the zone prefect in the exercise of his powers. As part of this, he leads and coordinates the work of all the regional health agencies in the defence zone. The regional health agency of the head of the zone is therefore referred to as the zone regional health agency.