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What to Do After a Nuclear Explosion: Survival Guide

Immediate Actions After a Nuclear Explosion

If you see a bright flash or mushroom cloud, act immediately. Every second counts.

First 10 Seconds: Take Cover

  • Do NOT look at the fireball — it can cause permanent blindness
  • Drop and cover — get behind any solid object
  • Get inside — any building is better than being outside
  • Move to the center of the building, away from windows

    • First 15 Minutes: Find Better Shelter

  • Move to the lowest floor or basement
  • Concrete and brick provide the best shielding
  • Close all windows and doors
  • Turn off ventilation systems (HVAC, fans)
  • Remove and bag outer clothing if you were outside

    • First 24 Hours: Shelter in Place

    The most dangerous fallout settles within the first few hours. The 7-10 rule applies:

  • For every 7× increase in time, radiation drops by 10×
  • After 49 hours, radiation is 1/100th of initial levels

    • Do:

  • Stay inside for at least 24 hours
  • Listen to emergency broadcasts
  • Ration food and water
  • Cover nose and mouth if dust is present

    • Don't:

  • Go outside to look
  • Use the phone unless it's an emergency
  • Eat or drink anything that was uncovered and exposed

    • After 24-72 Hours

  • Follow government evacuation instructions
  • If you must go outside, cover all skin
  • Decontaminate by showering (don't scrub — it pushes particles into skin)
  • Seek medical attention for radiation symptoms

    • Check your nuclear fallout risk

    Use our free calculator to see your survival rate

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