Main content | back to top
What Is The Community Warning System
The Community Warning System is coordinated by the Contra Costa County Community Awareness & Emergency Response (CAER) to notify communities in Contra Costa County of chemical emergencies.
The Community Warning System safety sirens are tested on the first Wednesday of every month at 11:00 a.m. in industrial areas of East, West, and Central Contra Costa- County. In the event of a real emergency, safety sirens in the affected areas will be sounded to alert you to "shelter-in-place" and turn on your radio or television for information.
- Go inside
- Shut all doors, close and lock all windows
- Turn on your radio or TV for further instructions
- Don't use your phone unless there is a life-threatening emergency
- After the shelter-in-place alert is over, open your windows and doors and air out your house
For more information about the Community Warning System, call (925) 313-9296.