WASHINGTON – Millions of cellphones will beep, chirp and vibrate at exactly 2:18 p.m. Wednesday.

Don't panic.

The Federal Emergency Management Agency is conducting a nationwide test of its Wireless Emergency Alerts (WEA), similar to the ones conducted on radio and television. In fact, radio and TV will start broadcasting similar messages as part of its Emergency Alert System (EAS) at precisely 2:20 p.m.

"The purpose of the test is to ensure that EAS and WEA are both effective means of warning the public about emergencies, particularly those on the national level," FEMA said in a release. Testing of public alert and warning systems helps to assess the operational readiness of alerting infrastructure and to identify any needed technological and administrative improvements.

Cell towers will broadcast the WEA test for approximately 30 minutes. Cellphones that are switched on, within range of an active cell tower and whose wireless provider participates in WEA, should be capable of receiving the test message.

The cellphone message will have a header that reads "Presidential Alert" and the following text: "THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed.”

It should appear only once.

This will be the first national test of the cellphone alerts. The system is used to warn the public about dangerous weather, missing children and other critical situations while also providing the president the capability to address the nation during a national emergency.

The exercise is being held in cooperation with the Federal Communications Commission and the National Weather Service and with the participation of the communications industry.

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