There was probably an alarming sound coming from your phone, television, or radio around 2:18 p.m. Eastern Time. Don’t panic. This was only a test.

FEMA and the FCC plan to test the national public alert and warning system on Wednesday.

On Wednesday, nearly all smartphones connected to a cellular network in the U.S. made an alert sound displayed the following message: “THIS IS A TEST of the National Wireless Emergency Alert System.”. The purpose is to maintain and improve alert and warning capabilities at the federal, state, local, tribal and territorial levels as well as evaluating the nation’s public alert and warning capabilities. The public does not need to take any action.”

FEMA tests ensure that the U.S. government can reach Americans in an emergency. Every three years, FEMA must conduct a nationwide test under a law passed in 2015.

In a video, FEMA administrator Deanne Criswell said the agency wants to keep you informed when it counts.

TV and radio broadcast a similar message simultaneously. A third nationwide test of the alert system is currently being conducted by FEMA. The last one took place in August 2021. A message can also be sent by the president using the same system that was tested in 2018.

When a smartphone is on, the alert sound cannot be turned off. Subscribers and sign-ups are not required. Unlike some government alerts, such as Amber alerts, which are opt-out settings on iPhones and most Android smartphones, this test cannot be opted out, FEMA said.