There is a specific Wireless Emergency Alerts (WEA) service that is provided by the government to the owners of iPhone to the networks. There was Carrier Settings Update in 2013
In this update, the alerts were added which are normally of the four types. Being an iPhone owner, you can easily turn off three of them.
If you want to turn Emergency Alerts off on the Apple Devices, follow the steps below:
- Go to Setting, then go to notifications options and then scroll down to option of Government Alerts option that is at that is at the bottom.
- After that, choose the option for AMBER alters, Public Safety Alerts and emergency Alerts and switch to off or on.
- If your device is on silent mode, you can receive emergency alerts quietly. For this purpose, you will need to toggle to Emergency Alerts -> Always deliver -> OFF (grey switch).
You cannot turn off the Federal Emergency Management Agency (FEMA) Presidential Alerts. They are delivered to all US citizens through wireless.