An Emergency Alert Test Sounded On All US Cellphones, TVs & Radios; Here's What Happened

Your electronic devices may have alarmed you on Wednesday — and there's a reason for that.

A nationwide test of the federal emergency alert system started broadcasting just before 2:20 p.m. EDT to cellphones, televisions and radios across the United States. The test occurred simultaneously in every time zone coast to coast.

Most Americans with wireless cellular devices should have received an emergency alert message on their phones. Those whose televisions or radios were turned on when the test occurred should have seen or heard an alert message, too.

Russia tested its own emergency public warning system on Wednesday, sounding sirens across the country and interrupting some television and radio broadcasts, Reuters reported.

Here's what to know about the U.S. test:

What is an emergency alert?

The Federal Emergency Management Agency conducted Wednesday's test in coordination with the Federal Communications Commission. Emergency alert messages that made up the test were divided into two groups — the Emergency Alert System for radios and televisions, and the Wireless Emergency Alerts for wireless phones — although both happened at once. 

Wednesday marked the seventh nationwide test of the Emergency Alert System. Six previous tests were conducted over the years between November 2011 and August 2021. This was the third nationwide test of wireless alerts, and the second nationwide test transmitted to all cellphones, FEMA said in a statement. 

As the Wireless Emergency Alert test was sent out to phones, the Emergency Alert System test was sent to televisions and radios.

"With the combination, you're going to catch a wide swath of people," said Joseph Trainor, a core faculty member at the University of Delaware's Disaster Research Center, who studies the design of disaster warning systems and how they operate, with a particular focus on mobile warning systems and smart warning systems. Trainor has worked with government agencies before, in the U.S. and abroad, to develop their emergency warning systems and procedures. 

"We know that they are effective systems," Trainor told CBS News. "Like any system, there are strengths and weaknesses. How many characters you can use, how much you can transmit, how fast you can get it out. Every system has limits, and that's why we tell people, when we are giving advice about building warning systems, you don't ever want to rely on just one thing."

Why was the alert system being tested?

Since 2015, FEMA has been required under federal law to test the Integrated Public Alert and Warning System at least once every three years, and those tests can involve the Emergency Alert System, wireless alert system, and other alerts and warnings. 

Wednesday's test was conducted to evaluate the technological capabilities of the national alert system to reach and inform as many people as possible in case of a widespread emergency. A backup date of Wednesday, Oct. 11, was scheduled in case other emergencies, like extreme weather, prevented it from going forward as planned on Oct. 4. 

"If at some point the time comes that we need to put a wireless emergency alert to the entire nation, for some really serious, catastrophic event, the ability to send out messages in little places, smaller counties, smaller geographic areas, is not the same as having the capacity to distribute those messages across the entire system," Trainor explained. "So, one of the reasons that you might do something like this is to test the technological limits of the system, to make sure that it's available in that way."

Spokespeople from FEMA and the FCC said both agencies are confident the emergency alert system works as intended for television and radio broadcasts as well as mobile phones. But conducting Wednesday's test still allowed them to gather valuable information from the companies that participated. 

"When it comes to evaluating the results of the alerting tests, the FCC is collecting information both from EAS participants and participants in WEA," a spokesperson for the FCC said Tuesday. "So for all EAS participants, and that includes broadcasters, cable companies, satellite TVs, and so forth, they're required to file information with the FCC about how the test went for them." 

"They're required to report to the commission whether they received the alerts, whether they were able to transmit it back out to the public, whether they encountered any technical issues in the course of sending those alerts out, and the FCC then analyzes that information to determine any opportunities of improvement of the system as a whole," the spokesperson continued, noting that a similar evaluation process will happen between the FCC and the nine largest U.S. wireless providers that participated in the test. 

Providers will essentially answer a set of survey questions, asking for the exact time each provider received the test from the integrated public system and the time they transmitted out to cell towers, and whether they encountered any technical issues along the way.

"When we receive those responses, we can take a look at that and identify any weaknesses in the system and any opportunities for improvement," the spokesperson said.

The test could also help raise public awareness about what to do in a national emergency, similar to the ways in which running a fire drill inside an office building or a school helps familiarize people with the process of an evacuation. 

"When an alert comes in like this, it makes people ask, 'What is this? What am I doing here?'" Trainor said. "And there's a natural process for people when it comes to warnings, we sometimes call it milling, where they have to kind of process it, and make sense of what's going on, and decide if they're going to do something. You know, 'What is this thing? Is it real?'"

Exposure to emergency alert tests may prepare people to act quickly in the event of a real emergency, he said.

"Warning systems and alert systems, they get you started," Trainor said. "But there's a human decision process and, if it's the first time you've ever seen one in a real event, it's going to take you longer to make sense of what it is, and get the information you need, and process it to be able to make decisions."

How does the wireless test work?

The wireless portion of the test was launched through FEMA's Integrated Public Alert and Warning System, a platform that unifies national alert systems for a range of mediums and allows officials to send authenticated emergency messages quickly to the public through multiple communications networks, including television, phone and radio. Wednesday's test was administered using a code sent to cellphones, according to FEMA.

Wireless alerts are created by authorized federal, state, local, tribal and territorial government agencies, and sent to participating wireless providers through the Integrated Public Alert and Warning System, or IPAWS.

Wireless providers that participate in the integrated public system then dispatch alerts from cell towers to compatible phones in geo-targeted areas.

"The idea is that all of these systems are trying to work together to get information out, in as many ways as possible, to the right people," Trainor told CBS News. "So that folks have the information to make good choices about the risks around them."

Trainor noted that research into wireless alerts, like texts, show they tend to be "very good at getting people's attention."

"When your cellphone makes a noise, you look," he said. 

FEMA said no personal data was collected from anyone's devices in the process.

How long was the wireless emergency alert test?

Cell towers are broadcasting the emergency alert test for 30 minutes, which started at approximately 2:20 p.m. EDT on Wednesday, but each phone should only receive it once.

During that half-hour, wireless phones that were turned on, not in "airplane mode" and compatible with the alerts should have received a test message, as long as they were located within a certain range of an active cell tower and their wireless provider participates in FEMA's wireless alert system, the agency said. All major wireless providers participate in the system. Some older devices may not be compatible with wireless alerts.

FEMA noted that, for people who were in the middle of a phone call at the time of the alert, the message and tone would be delayed until they hung up.

People who received the test alert on their phones should have seen a message that read: "THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed."

The alert was translated automatically when it appeared on cellphones where the language settings were set to Spanish. That message read: "ESTA ES UNA PRUEBA del Sistema Nacional de Alerta de Emergencia. No se necesita acción."

Alerts were "accompanied by a unique tone and vibration," to make the wireless test more accessible for people with disabilities, according to FEMA.

Was it possible to opt out of the wireless test?

People can elect not to receive certain emergency alert messages to their cellphones from local authorities, or in some instances, simply decide whether to subscribe or not to a specific set of emergency alerts put out by a particular agency. On the other hand, it was not possible to opt out of Wednesday's test of the national wireless alert system.

"Part of the reason why the system works the way it does, is that a cellphone has the ability to pick up broadcast signals," Trainor said. He noted that the integrated public alert system relies on broadcast technology that transfers information about emergencies to cellphone towers, and each of those towers then beams the information out to whichever wireless devices are geographically within its reach.

Before Wednesday, news of FEMA's test recently sparked a wave of conspiracy theories online, which were not based on reality and misrepresented how the technology works. 

How does the test work for TVs and radios?

The Emergency Alert System test was scheduled to launch at the same time as the wireless portion, but only lasted for one minute. 

When it launched, the test interrupted regular television and radio programming, regardless of which channel you'd been watching or which station you were tuned into, to broadcast a message that said: "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."

FEMA said ahead of the Emergency Alert System test that it would be "similar to the regular, monthly EAS test messages with which the public is familiar."