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Business and government sometimes use chemicals or products that can be hazardous to the health of the public. Normally these chemicals pose minimal risk to the public; however, during a fire, explosion, or other disaster, these chemicals can be released into the environment and become severe threats to health.

The chemicals in our region that are most likely to be involved in hazardous materials accidents are chlorine, ammonia, and explosives. If you work with these, you should be sure to know the appropriate safety measures to take to reduce the risk of an accident.

This fact sheet describes what to do if you are exposed to hazardous chemicals or are near a location where a hazardous materials accident is occurring.

If you witness a hazardous materials accident, call 911 or your local fire department immediately!


What to do if you hear a warning signal

  • Listen to local radio or television stations for further information.
  • Always evacuate if told to do so.
  • Stay away from the accident site.
  • If you are outside - stay upwind, uphill, or upstream. Try to go at least one-half mile from the danger area.
  • Do not handle any items that could generate a spark or fire. Leave the area immediately!
  • If you suspect that a gas or vapor has entered the building, breathe through a wetted cloth or towel, and leave the area.
  • If you are in a car when a hazardous gas is released, close the car windows, shut off the outside air intake (or completely turn off the ventilation system), and leave the area.

What to do when you have time after a warning has been issued

  • Close windows and vents.
  • Turn off attic fans and other ventilation systems.
  • Seal all windows and other entry routes.
  • Set ventilation to 100% recirculation. If that is not possible, turn off the ventilation system.
  • Return to the building only when directed.
  • After returning, open windows and doors, and set ventilation system to bring in maximal outdoor air.

What to do if you had contacdt with a hazardous material

  • Avoid contact with any chemicals whenever possible.
  • Do not eat or drink any food or water that may have been contaminated.
  • If you were exposed to hazardous materials, you may be contaminated and can contaminate others.
  • For severe injuries due to the exposure, call 911.
  • Consult the Material Safety Data Sheets, if available.
  • Shower to remove the chemical, unless water will cause additional injury.
  • If you are uncertain about how to remove the chemical from your body, call the Washington Poison Center at 800-222-1222.
  • Consult your health care provider for additional medical advice as needed.