A nationwide Emergency Alert System (EAS) test will be conducted Wednesday and radios, televisions and certain cellphones will be alerted.
The test, which is being run by the Federal Emergency Management Agency in coordination with the Federal Communications Commission, will begin at approximately 2:20 p.m. ET.
The EAS portion of the test, which will occur on radios and televisions, is scheduled to last about one minute, and the Wireless Emergency Alert (WEA) to cellphones, whose users have opted into receiving messages, should only be received once.
"The purpose of the Aug. 11 test is to ensure that the EAS and WEA systems continue to be effective means of warning the public about emergencies, particularly those on the national level," a FEMA press release said. "Periodic 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."
The message, according to FEMA, should read: "THIS IS A TEST of the National Wireless Emergency Alert System. No action is needed."
The message will display in either English or Spanish, depending on the language settings of the device, according to the FEMA press release.
Wednesday's test is the sixth nationwide EAS test, the second WEA test and the first WEA test on a consumer opt-in basis.
"Emergency alerts are created and sent by authorized federal, state, local, tribal and territorial government agencies," according to FEMA.
According to FEMA, the two government agencies are coordinating with "wireless providers, emergency managers and other stakeholders" to "minimize confusion" and "maximize the public safety value of the test."
If Wednesday's test is canceled, a backup testing date is scheduled for Aug. 25.