These frequencies may be nationwide and within the state for incidents. National Flight Following is used to monitor interagency and contract aircraft. This is used for flight following official aircraft flying point to point. All dispatch centers have access to this frequency. National Air Guard is used for emergency aviation communications. It is mandatory for dispatch centers to monitor this frequency with aircraft assigned to an incident. National Interagency Air Tactics support air/air and air/ground communications on incidents after approval of management. These are in addition to regional predetermined frequencies. Government Wide Area common are for logistical traffic only, and may be used by any federal agency.