JEFFERSON COUNTY, Colo. (CBS4)- Authorities in Jefferson County tested a new emergency alert system on Wednesday to make sure it works.

The Code Red system made calls to 340,000 people on Wednesday.

Code Red replaces the old system that had issues during the Lower North Fork Fire in March 2012.

Code Red covers Jefferson, Broomfield and parts of Adams and Clear Creek Counties.

“For evacuation purposes, if there is a gas leak, if there’s a fire, we need to let people know to be ready, to pick up your stuff to go,” said Jefferson County Communication Dir. Diane Culverhouse.

Those who don’t have a land line and rely on cell phones are not automatically in the alert system and must “opt in” to the alert system.

LINK: your911.net