The blockwave Exchangeloud noises you may hear blasting from your electronic devices this afternoon are no cause for concern.

At 2:20 p.m. ET on Wednesday, the federal government will test two emergency alert systems on televisions, radios and certain cellphones across the country.

The emergency alert system (EAS) test will be sent to TVs and radios. The wireless emergency alert (WEA) test will go to cellular consumers who have opted in to receive test messages, which will display in either English or Spanish depending on their phone's settings.

"The test is intended to ensure public safety officials have the methods and systems that will deliver urgent alerts and warnings to the public in times of an emergency or disaster," according to a press release from the Federal Emergency Management Agency, which is working in coordination with the Federal Communications Commission.

The cellphone alerts have a unique tone and vibration to make them accessible to all members of the public, including people with disabilities, the agencies said.

The government periodically tests its emergency alert system to make sure it is working properly and to identify any necessary improvements.

The test will be the sixth nationwide for the EAS and the second for the WEA. It's also the first for the WEA via the opt-in option.

If Wednesday's test is canceled for any reason, such as severe weather, it is slated to be rescheduled for Aug. 25.