https://crtc.gc.ca/eng/television/services/alert.htm
Can I opt-out of receiving alerts?
No. Given the importance of warning the Canadian public of imminent threats to the safety of life and property, it is not possible to opt out of receiving alerts.
The CRTC requires service providers to distribute alerts to all compatible cellphones connected to an LTE or newer network in the area covered by the alert.
Depending on your phone, you may be able to choose how it alerts you. For example, you may be able to adjust the alarm by placing your phone on the lowest volume setting, placing your phone in “Do Not Disturb“ or “Silent Mode,” or by setting your device to vibrate.
Read about our testing of mobile phone response to emergency alerts: Testing the Response of Mobile Telephones to Wireless Public Alerts | CRTC
