Common Alerting Protocol

Common Alerting Protocol (CAP) is an international, non-proprietary digital message format for exchanging all-hazard emergency alerts.

The CAP standard was developed by the Organisation for the Advancement of Structured Information Standards (OASIS) and is based on best practices identified in academic research and practical experience. 

MCDEM leads the CAP-NZ Working Group, with members from many government agencies, research institutes, and emergency hardware and software suppliers.

Benefits of CAP

  • A single CAP message can activate multiple compliant warning systems, delivering consistent information to all, thereby increasing the credibility of the alert when people hear exactly the same words from a number of sources.
  • CAP offers the ability to geo-target alerts to a defined warning area.
  • CAP offers the capability to include content such as photographs, maps, streaming video and more. This better serves the needs of hearing or visually impaired persons.
  • CAP offers the ability to issue alerts in multiple languages.

Why CAP is used

CAP is used throughout the world, and many software and hardware systems are already set up to use CAP because of its widespread uptake. New Zealand CAP alerts can be used by other countries, and vice versa.

For example, Google Public Alerts monitors international CAP alerts and, within an affected area, notifies mobile devices that use Google Now. This is a valuable extra channel that gets the message through to people, without having to download an app.

CAP-NZ Technical Standard 

The CAP-NZ Technical Standard provides guidance for a consistent approach to implementing CAP in New Zealand. 

Download a copy of Common Alerting Protocol CAP-NZ Technical Standard [TS04/18] (pdf. 2mb)

Current users of CAP alerts in New Zealand

CAP is recognised as a standard for use across the New Zealand Government by Government Enterprise Architecture for New Zealand (GEA-NZ).

Alerting authorityCAP feedHazard
GNS Science Earthquake
MetService Severe weather
Civil Defence Emergency Management Groups Regional hazards