Graphic of a nuclear blast with a mushroom cloud engulfed in fire spreading over open terrain.
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Nuclear Explosion

Nuclear explosions can cause significant damage and casualties from blast, heat, and radiation but you can keep your family safe by knowing what to do and being prepared if it occurs.

A nuclear weapon is a device that uses a nuclear reaction to create an explosion.

Nuclear devices range from a small portable device carried by an individual to a weapon carried by a missile.

A nuclear explosion may occur with or without a few minutes warning.

Fallout is most dangerous in the first few hours after the detonation when it is giving off the highest levels of radiation. It takes time for fallout to arrive back to ground level, often more than 15 minutes for areas outside of the immediate blast damage zones. This is enough time for you to be able to prevent significant radiation exposure by following these simple steps:

GET INSIDE

Get inside the nearest building to avoid radiation. Brick or concrete are best.

Remove contaminated clothing and wipe off or wash unprotected skin if you were outside after the fallout arrived.

Go to the basement or middle of the building. Stay away from the outer walls and roof.

STAY INSIDE

Stay inside for 24 hours unless local authorities provide other instructions.

Family should stay where they are inside. Reunite later to avoid exposure to dangerous radiation.

Keep your pets inside.

STAY TUNED

Tune into any media available for official information such as when it is safe to exit and where you should go.

Battery operated and hand crank radios will function after a nuclear detonation.

Cell phone, text messaging, television, and internet services may be disrupted or unavailable.

HOW TO STAY SAFE IN THE EVENT OF A NUCLEAR EXPLOSION

Prepare NOW

Identify shelter locations. Identify the best shelter location near where you spend a lot of time, such as home, work, and school. The best locations are underground and in the middle of larger buildings.

While commuting, identify appropriate shelters to seek in the event of a detonation. 

Outdoor areas, vehicles, mobile homes do NOT provide adequate shelter. Look for basements or the center of large multistory buildings.

Make sure you have an Emergency Supply Kit for places you frequent and might have to stay for 24 hours. It should include bottled water, packaged foods, emergency medicines, a hand-crank or battery-powered radio to get information in case power is out, a flashlight, and extra batteries for essential items. If possible, store supplies for three or more days. 

Survive DURING

If warned of an imminent attack, immediately get inside the nearest building and move away from windows. This will help provide protection from the blast, heat, and radiation of the detonation.

If you are outdoors when a detonation occurs take cover from the blast behind anything that might offer protection. Lie face down to protect exposed skin from the heat and flying debris. If you are in a vehicle, stop safely, and duck down within the vehicle.

After the shock wave passes, get inside the nearest, best shelter location for protection from potential fallout. You will have 10 minutes or more to find an adequate shelter.

Be inside before the fallout arrives. The highest outdoor radiation levels from fallout occur immediately after the fallout arrives and then decrease with time.

Stay tuned for updated instructions from emergency response officials. If advised to evacuate, listen for information about routes, shelters, and procedures.

If you have evacuated, do not return until you are told it is safe to do so by local officials.

Be Safe AFTER

Immediately after you are inside shelter, if you may have been outside after the fallout arrived:  

Remove your outer layer of contaminated clothing to remove fallout and radiation from your body.

Take a shower or wash with soap and water to remove fallout from any skin or hair that was not covered. If you cannot wash or shower, use a wipe or clean wet cloth to wipe any skin or hair that was not covered.

Clean any pets that were outside after the fallout arrived. Gently brush your pet’s coat to remove any fallout particles and wash your pet with soap and water, if available.

It is safe to eat or drink packaged food items or items that were inside a building. Do not consume food or liquids that were outdoors uncovered and may be contaminated by fallout.

If you are sick or injured, listen for instructions on how and where to get medical attention when authorities tell you it is safe to exit.

Hazards related to nuclear explosions

  • Bright FLASH can cause temporary blindness for less than a minute.

  • BLAST WAVE can cause death, injury, and damage to structures several miles out from the blast.

  • RADIATION can damage cells of the body. Large exposures can cause radiation sickness.
  • FIRE AND HEAT can cause death, burn injuries, and damage to structures several miles out.
  • ELECTROMAGNETIC PULSE (EMP) can damage electrical power equipment and electronics several miles out from the detonation and cause temporary disruptions further out.

  • FALLOUT is radioactive, visible dirt and debris raining down from several miles up that can cause sickness to those who are outside.

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