In applications and services which support alerting, it is necessary to identify various information objects. Subsequent OIDs identify content included in alert messages or otherwise associated with the activity of alerting.
The procedures (and criteria for acceptance) for allocating subsequent arcs are described in WMO/TD No. 1556 "Administrative procedure for registering WMO alerting identifiers."
During the Common Alerting Protocol (CAP) Implementation Workshop, 17-18 June 2014, Negombo, Sri Lanka, clarification was sought on use of alerting OIDs by organizations that cannot issue public warnings, yet perform private or restricted alerting to those governmental authorities who issue public warnings. Examples of such organizations include motorway control centres, airports, power plants, chemical plants, and ambulance services. Their private alerts typically inform alerts issued publicly by alerting authorities such as fire-fighters, police, civil protection agencies, environmental authorities, etc. For this reason, it would be very useful if all alerting organizations (governmental as well as others) were to use officially registered alerting OIDs. Subsequent to the workshop, WMO clarified that it does not place any policy constraints on which alerting authorities are designated by national WMO Members, nor any constraints as to whether such authorities issue alerts publicly or privately. Therefore, assignment of OIDs nationally for use with private or restricted alerts from any recognized authority is entirely within the purview of each Permanent Representative with WMO.