The EAS alert will be sent to radio and television broadcasters, cable systems, satellite radio and television providers and wireline video providers, according to FEMA.
The message was broadcast by cell towers for 30 minutes, meaning some devices may have received it later than others.
The special Presidential Alert will be pretty similar to any emergency alert you've gotten before. Others didn't get it at all. This will happen even if your phone is on silent mode. It hasn't said yet whether the test went well.
Can I silence my phone or turn off the alert?
In New York, U.S. District Judge Katherine Polk Failla rejected a last-minute effort to block the test. But FEMA officials said the administration can only send these alerts for emergencies affecting the whole country or if the public was in danger, according to Bloomberg.
On Wednesday, the Integrated Public Alert and Warning System sent a test message to everyone using a cellphone in the United States that runs on a network operated by a carrier participating in the Wireless Emergency Alert system.
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He said: " OPEC and OPEC nations are as usual, ripping off the rest of the world , and I don't like it, nobody should like it".
So we asked FEMA why some people didn't get the alerts.
The law establishing the alert says it can not be sent out for any reason other than "a natural disaster, act of terrorism or other man-made disaster or threat to public safety", according to NowThis. But, from this point on, the test should occur every three years. It is being completed in coordination with the Federal Communications Commission. The test is made available to EAS participants, officials said.
FEMA says it will sound like an AMBER Alert or weather-related warning with a subject saying "Presidential Alert".
"The Wireless Emergency Alert (WEA) system is used to warn the public about risky weather, missing children, and other critical situations through alerts on cell phones".
All freaking out aside, the wireless alert system actually launched in 2012 when Barack Obama was president, so it's been around for a while. USA cellphone users are not able opt out of presidential alerts. A message will also appear on your screen that says, "THIS IS A TEST of the National Wireless Emergency Alert System".
A group of New Yorkers is suing to be able to opt out of the alert, claiming it infringes on their First Amendment rights.