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Five different hazardous materials signs showing different numbers and warnings

Hazardous Materials Incidents

Before a Hazardous Materials Incident

During an Incident

After an Incident

Hazardous materials can include explosives, flammable and combustible substances, poisons and radioactive materials. Emergencies can happen during production, storage, transportation, use or disposal. You are at risk when chemicals are used unsafely or released in harmful amounts where you live, work or play.

Before a Hazardous Materials Incident

Many communities have Local Emergency Planning Committees (LEPCs) that are responsible for collecting information about hazardous materials in the community and planning. This information is available to the public upon request. Contact your local emergency management office for more information on LEPCs.

Protect yourself from a hazardous materials incident:

an emergency supply kit including scissors, duct tape, plastic sheeting and a flashlight.

During a Hazardous Materials Incident

Listen to local radio or television stations for detailed information and follow instructions carefully. Remember that some toxic chemicals are odorless.

illustration of an evacuation map after a hazardous materials incident

If asked to evacuate:

  • Do so immediately.
  • Stay tuned to the radio or television for information on evacuation routes, temporary shelters and procedures.
  • If you have time, minimize contamination in the house by closing all windows, shutting all vents and turning off attic fans.
  • Take pre-assembled disaster supplies.

Remember to help your neighbors who may require special assistance — infants, elderly people, and people with access and functional needs.

If asked to stay indoors:

  • Bring pets inside.
  • Close and lock all exterior doors and windows. Close vents, fireplace dampers and as many interior doors as possible.
  • Turn off air conditioners and ventilation systems, or set ventilation systems to 100 percent recirculation so that no outside air is drawn into the building.
  • Take shallow breaths through a cloth or a towel if gas or vapors could have entered the building.
  • Avoid eating or drinking any food or water that may be contaminated.
  • Go into your pre-selected shelter room.
  • Seal gaps under and around the following areas with wet towels, plastic sheeting, duct tape, wax paper or aluminum foil:
    • Doorways and windows
    • Air conditioning units
    • Bathroom and kitchen exhaust fans
    • Stove and dryer vents with duct tape and plastic sheeting

If outside:

  • Stay upstream, uphill and upwind. In general, try to go at least a half mile (usually 8-10 city blocks) from the danger area.
  • Do not walk into or touch any spilled liquids, airborne mists or condensed solid chemical deposits. Try not to inhale gases, fumes and smoke. If possible, cover mouth with a cloth or mask while leaving the area.

Stay away from accident victims until the hazardous material has been identified.

If in a car:

  • Stop and seek shelter in a permanent building.
  • If you must remain in your car, keep car windows and vents closed and shut off the air conditioner and heater.

After a Hazardous Materials Incident

Illustration of a woman sitting on the couch listening to the radio looking out the window at two first responders putting a stretcher into an ambulance.
  • Listen to local radio or television stations for the latest emergency information.
  • Go to a designated public shelter if you have been told to evacuate or you feel it is unsafe to remain in your home. Text SHELTER + your ZIP code to 43362 to find the nearest shelter in your area (example: shelter 12345).
  • Act quickly if you have come into contact with or have been exposed to hazardous chemicals.
  • Follow decontamination instructions from local authorities.
  • Seek medical treatment for unusual symptoms as soon as possible.
  • Place exposed clothing and shoes in tightly sealed containers.
  • Advise everyone who comes in to contact with you that you may have been exposed to a toxic substance.
  • Return home only when authorities say it is safe. Open windows and vents and turn on fans to provide ventilation.
  • Find out from local authorities how to clean up your land and property.
  • Report any lingering vapors or other hazards to your local emergency services office.

Last Updated: 09/20/2022

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