The Department of Energy (DOE) will set off their emergency sirens between 8:00 a.m. and 11:00 a.m.
It's important to not panic or worry if you hear the siren.
DOE leaders say there is no danger. This is all because of an emergency drill taking place on the Hanford Site.
Prior to the siren, people should hear a message which states "this is an exercise message."