Massive Emergency Alert Test Today: 'This Is Only A Test'

Today at 2:20 p.m. EDT, every TV, radio and cellphone in the United States should blare out the distinctive, jarring electronic warning tone of an emergency alert.

It's a test – only a test.

Officially, the trial is called the Nationwide Emergency Alert Test. You know it's a test and not an actual emergency because it's accompanied by an explanation of the test.

No, it's not a national conspiracy to infect people with nanoparticles, reports USA Today. Yes, it does go back all the way to the Cold War in the 1950s. No, we can't play you the tone – we could get hit with a big fine if we did.

But mostly the test is an important way to make sure that if something really bad – and really big – happens, Americans can be warned quickly.

Here's what to know about the test:

What is the emergency alert test? How does it work?

The national test consists of two parts, which occur in conjunction with one another, in order to test the Emergency Alert System and the Wireless Emergency Alerts, according to FEMA.

The WEA will be directed to all cellphones, while the EAS will notify all radio and television broadcasters, cable systems, satellite radio and television providers and wireline video providers.

The message will be heard and seen pretty much everywhere. It's being conducted with the participation of radio and television broadcasters, cable systems, satellite radio companies and cellphones networks.

All across the United States, broadcast TV shows and radio will be interrupted as the emergency message goes out. That message will say:

“This is a nationwide test of the Emergency Alert System, issued by the Federal Emergency Management Agency, covering the United States from 14:20 to 14:50 hours ET. This is only a test. No action is required by the public."

Cellphones will get the warning as a tone, a vibration and as a text message:

“THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed.”

Phones on which the main menu set to Spanish will see this: “ESTA ES UNA PRUEBA del Sistema Nacional de Alerta de Emergencia. No se necesita acción.”

When will the emergency alert test happen?

The alert will air at the same moment across every time zone in the country starting at 2:20 p.m. EDT on Wednesday.  The time will vary across time zones, so look to see when you might be alerted. 

• 2:20 p.m. EDT
• 1:20 p.m. CDT
• 12:20 p.m. MDT
• 11:20 a.m. PDT
• 10:20 a.m. ADT
• 8:20 a.m. HST

The test is scheduled to last approximately one minute. It will only go out once, there will be no repeats.