Sirens and Refineries
Sirens are tested on the first Wednesday of every month at 11:00am. For the remaining Wednesdays, a more quiet and low “growl” test is performed at 11:00am.
Contra Costa County Health Services, Hazardous Materials Program, established an Incident Notification Policy that includes criteria for the various public notifications requirements during hazardous materials incidents.
A siren is an alerting device that alerts you to a possible hazard in your area. The sound of a siren is meant to draw your attention away from your daily activities. You may work or live near a hazardous materials facility, dam, levee, or potential hazards. The best response to hearing a siren is to take protective action and SHELTER, SHUT, & LISTEN. Shelter yourself, your family, and your pets (if possible) inside, away from the outside air. Shut and lock all doors and windows. Turn off vents, air conditioners, and fans. Listen to telephone notifications, radio, TV broadcasts, and other official information sources to learn important details about how to protect your health and how long to shelter.