NPAS is based on the Common Alerting Protocol (CAP), an international open data standard for exchanging public warnings and emergency messages between alerting technologies.

The Canadian Profile of the Common Alerting Protocol (CAP-CP) is a set of rules, and managed lists of values, that are recommended for use in Canada.

CAP-CP is currently published as three documents:

  1. Introduction and Rule Set
  2. Event References
  3. Location References.

The current and archived versions of these documents are available at