5.16.4.3 Mobility Restrictions and Access Restrictions for Emergency Services

When Emergency Services are supported and local regulation requires IMS Emergency Sessions to be provided regardless of Mobility Restrictions or Access Restrictions, the Mobility Restrictions or Access Restrictions (see clause 5.3.4.1) should not be applied to UEs receiving Emergency Services. Additionally, due to Mobility Restrictions or Access Restrictions (e.g. CAG restrictions) for normally registered UEs, that have established both non-emergency PDU Sessions and emergency PDU Session, the AMF indicates to the SMF to perform a local release of all non-emergency PDU Sessions via PDU Session Release procedure as specified in clause 4.3.4 of TS 23.502 [3]. The UE locally releases non-emergency PDU Sessions. The AMF and the UE behave as if the UE is emergency registered as described in TS 24.501 [47].

When the (R)AN resources for Emergency Services are established, the ARP value for Emergency Services indicates the usage for Emergency Services to the 5G-AN.

During handover, the source NG-RAN and source AMF ignore any UE related restrictions during handover evaluation when there is an active PDU Session associated with emergency service.

During Mobility Registration Update procedures, including a Mobility Registration Update as part of a handover, the target AMF ignores any Mobility Restrictions or access restrictions for UE with emergency services where required by local regulation. Any non-emergency services are not allowed, by the target network when not allowed by the subscription for the target location. To allow the UE in limited service state (either Emergency Registered or registered for normal service) over a given Access Type to get access to normal services over this Access Type after the Emergency Session has ended and when it has moved to a new area that is not stored by the UE as a forbidden area, after allowing a period of time for subsequent Emergency Services, the UE may explicitly deregister and register for normal services over this Access Type without waiting for the emergency PDU Session Release by the SMF.

This functionality applies to all mobility procedures.