(KGTV) - You're sleeping, or going about your day, or at work and your phone sounds off. A loud ringing blares, drawing your attention to your phone's screen (or silence button).
"[Insert emergency warning here.]" You and those around you have just received wireless emergency alerts (WEA).
Most WEA are typically used for weather or Amber Alert situations but as seen in mid-January, can be used during a far worse scenario.
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WEA allow emergency messages concerning public safety to be distributed to masses, targeted geographically to phones in a text-like message. The system originated in 2008 in accordance with the Warning, Alert and Response Network (WARN) Act. Since it became instituted in 2012 more than 30,000 alerts have been sent.
HOW IT WORKS...
Authorized national, state or local government authorities have the ability to send out WEA. All an authorized agency has to do is send the alert through FEMA's Integrated Public Alert and Warning System to participating wireless carriers, according to the FCC.
The alert is then fed to the affected region(s).
Customers don't need to sign up for alerts and they are free. They also do not track users.
Alerts are limited to 90 characters, so it's advised to follow up by turning to local media and/or officials for more details.
WHO GETS THEM...
Alerts are sent to users within a coverage area designated as the best approximate zone of the emergency at hand.
Even if someone is from out of state, if they are in an alert zone with a WEA-capable device they'll get the message.
These alerts must be a critical emergency situation defined as either an alert issued by the President of the United States, alerts involving imminent threats to safety or life, or Amber Alerts. Some wireless carriers allow customers to block all but presidential alerts. The WARN Act prevents blocking presidential alerts.
CARRIERS AND PHONES...
Some phone carriers and phone models may not offer WEA.
Most wireless carriers offer the alert system, but some may only in certain coverage areas or on certain devices. Customers can easily check with their phone carrier whether they can receive the alerts on their phone or in their area.
Even those with a WEA-enabled device, however, won't receive the alert if their provider isn't offering the service in their current location, or if their device is roaming on another provider's network that doesn't support the service.
The FCC requires wireless carriers not participating in WEA to alert their customers.
If ever unsure, it's important to follow up with a wireless carrier with any questions.
For more information, check out the FCC's explainer on WEA.