FEMA and the FCC say it's important to do a first-ever nationwide test of their Emergency Alert System, but they don't want to panic the nation's citizenry in the process.

So they're trying to spread the word about the test which will take place at 1:00 p.m. Tulsa time on Wednesday.

Hear extended interview w/ FEMA's Jacqueline Chandler

The test was originally schedule to last as long as three-and-a-half minutes, but FEMA spokeswoman Jacqueline Chandler says that has now been shortened to 30 seconds.

"This was done to reduce the disruption to the American public, while still maintaining our ability to test the system's nationwide capabilities," she said.

Authorities say the test will look and sound very similar to the local EAS alerts that are broadcast on a regular basis.

The alert will be broadcast on every radio and TV channel in the nation, including cable and satellite providers.

Cell phones and the internet are not affected.