To inform you of a nearby need for CPR, a special notification called a “critical alert” will be sent to your mobile device (similar to an Amber alert). Critical Alerts, if enabled, override the Do Not Disturb setting on your device and play the alert sound even when your device is muted.

When you open the notification, the app screen will display your current location, the reported location of the cardiac arrest victim, and any nearby Automated External Defibrillators (AEDs). 

The brief video below provides an overview of PulsePoint Respond, including an example of the CPR-needed activation sequence (beginning at 1:47).