MHEWC-III Learning Event: Common Alerting Protocol (CAP)

The Common Alerting Protocol (CAP), a digital format for exchanging emergency alerts, allows a consistent alert message to be disseminated simultaneously over multiple communications pathways. By normalizing alert data across threats, jurisdictions, and warning systems, CAP also can be used to detect trends and patterns in warning activity, such as trends that might indicate an undetected hazard or hostile act. From a procedural perspective, CAP reinforces a research-based template for effective warning message content and structure.

A single emergency alert can trigger a variety of public warning systems, increasing the likelihood that people receive the alert by one or more communication pathways. 

The Common Alerting Protocol can:

• Add rich multimedia such as photographs, maps, streaming video and audio
• Geographically target emergency alerts to a defined warning area. This is limited only by the capacity of the delivery system used.
• Serve the needs of people who are deaf, hard of hearing, blind or low vision
• Send alerts in multiple languages

CAP Benefits

As more systems are built or upgraded to CAP, a single alert can trigger a wide variety of public warning systems, increasing the likelihood that intended recipients receive the alert by one or more communication pathways. CAP also provides the capability to include rich content, such as photographs, maps, streaming video and more. It enables geo-targeting alerts to a defined warning area, limited only by the capacity of the delivery system used.