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Home > Health Topics > Podcasts > When and How to Shelter in Place

When and How to Shelter in Place

July 2, 2009

William Walker, MD
Contra Costa Health Services

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See our Shelter in Place information and links.

The possibility of disaster is very real in Contra Costa County. An accident at a refinery or chemical plant, or a collision involving a truck or train carrying chemicals, could release dangerous toxins into our air.

The potential of hazardous materials accidents makes it important for residents to know how to shelter-in-place.

I'm Dr. William Walker, Director of Contra Costa Health Services, here to talk about how you should respond to shelter-in-place alerts, such as our safety sirens.

The safety sirens are part of our county's community warning system. When I hear the siren or am instructed to shelter in place, I follow three simple steps to ensure my safety: Shelter, Shut and Listen.

First, find shelter. Whether you are at home, work or the market, go inside the nearest building. If your children are at school, do not leave to get them. You could expose yourself to hazardous chemicals by going outside. Schools have plans to protect your children during such events.

If you are home, bring your pets inside if possible.

Second, shut and lock all windows and doors. Locks create a tighter seal. Also, turn off any heating or cooling fans that use outside air. If you have a fireplace, close the damper to prevent air from entering your home through the chimney.

Once you are safely secured, turn on your radio and television and listen for further instructions. The county's Community Warning System sends updates directly to the media. Public-access stations, such as KCBS 740 AM and KGO 810 AM will have ongoing status reports.

We also post information on our website. If you have Internet access, you can check for updates at

Unless you have a life-threatening emergency, it is best to not use your telephone. This way, lines will be left open for emergency communications.

Remain indoors until you hear the All Clear message. This message will be broadcast by the media and to telephones in the affected areas.

Once the All Clear is given, it is safe to go outside. Also open windows to air out your building.

These simple steps of Shelter, Shut and Listen will decrease your chances of exposure to toxic chemicals and will help protect you and your loved ones.

To find out more about what to do in an emergency, visit our website at

Thanks for listening.

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