Mobile phone users will receive a Presidential Alert test on their devices next week, according to an announcement issued by the federal government.

The test will take place at 1:18 p.m. Central Daylight Time on Sept. 20.

According to the announcement, the test of the Emergency Alert System and Wireless Emergency Alerts will be conducted by the Integrated Public Alert and Warning System, or IPAWS, which is part of the Federal Emergency Management Agency.

FEMA and the Federal Communications Commission will send a test wireless emergency alert  message to nearly all wireless devices in the United States, according to the announcement.

The message header will be "Presidential Alert," and the text will read, “This is a test of the National Wireless Emergency Alert System. No action is needed.”

According to the announcement, wireless customers can't turn off a Presidential Alert. Customers also can't opt out of the test.

Individuals whose phone is turned on, within range of an active cell tower and whose wireless provider participates in WEA, should be capable of receiving the message on their mobile phone.

The announcement stated that "just about every phone at your work place will receive the text ... which will likely set off an audible alarm for a short time."

According to the FEMA website, "the test will assess the operational readiness of the infrastructure for distribution of a national message and determine whether improvements are needed."

The Sept. 20 test is the fourth EAS nationwide test and the first national WEA test. Previous EAS national tests were conducted in September 2011, 2016 and 2017 in collaboration with the FCC, broadcasters and emergency management officials in recognition of FEMA’s National Preparedness Month.

FEMA's announcement stated that EAS is a national public warning system that provides the President with the communications capability to address the nation during a national emergency.

The test is made available to EAS participants including radio and television broadcasters, cable systems, satellite radio and television providers, and wireline video providers, and is scheduled to last approximately one minute. The test message will be similar to regular monthly EAS test messages that are familiar to many who watch television or listen to the radio.FE

FEMA noted some cell phones will not receive the test message, and cell phones should only receive the message once.

The WEA system is used to warn the public about dangerous weather, missing children and other critical situations through alerts on cell phones.

If circumstances such as a major weather event cause the IPAWS National Test to be postponed on Sept. 20, the backup date is Oct. 3.