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Know How to Shelter-in-Place

safety siren

What should I do when I hear the siren?

In the event of a chemical release, safety sirens in Contra Costa County's industrial corridor will sound to alert the public. If you hear the sirens, or are told by emergency authorities to Shelter-in-Place, take these actions:

  • Go inside (take pets with you)
  • Close and lock all windows and doors (locking provides a tighter seal)
  • Turn off all ventilation systems such as heating or air conditioning
  • Close all fireplace dampers
  • If there are gaps in windows or doors, seal with tape or damp towels
  • Tune to KCBS 740 AM on the radio for more information

How long will the sirens sound?

The sirens will sound initially for about three minutes. They will continue to be re-sounded periodically if the event continues. Shelter-in-Place alerts are also broadcast over weather radios in Contra Costa County, and the County operates a phone ringdown system that is activated for Shelter-in-Place alerts. What should businesses do during a Shelter-in-Place event? Shelter employees and customers in place, following the same steps as for a home. Close doors and windows, shut down heating and air conditioning systems, seal gaps and do not call 9-1-1 unless there is a medical emergency.

Where can people get information in languages other than English when the sirens sound?

Tune to CCTV, the County's TV station (check local cable listings for channel in your area). CCTV is connected to the CWS, so Shelter-in-Place information in English, Spanish and Tagalog will automatically scroll if there is an alert.

How will I know when the event is over?

County authorities will announce the “All Clear” via the news media. CAER recommends tuning an AM radio to KCBS 740.

Are the sirens tested?

The sirens are tested on the first Wednesday of each month at 11:00 a.m. Instead of three minutes, they are sounded for only about one minute during the test. If you hear the safety sirens at any other time, you should Shelter-in-Place.

How can I help spread the word about Shelter-in-Place procedures?

Download a flyer to post at your school or place of business (PDF)