What To Do In A Nuclear Attack: Step-by-Step Survival Guide

Before the Attack: Preparation

Surviving a nuclear detonation starts long before the sirens sound. Your primary goal is to establish a secure location and stockpile essential supplies well in advance. According to FEMA's official nuclear explosion preparedness guidance, preparation is the single most effective action a civilian can take.

• Identify the best fallout shelters near your home, work, and school. Look for thick concrete walls and subterranean levels. Large office buildings, parking garages, and government buildings often offer the best protection.
• Build an emergency supply kit with a minimum of 14 days of food and water. The CDC recommends at least one gallon of water per person per day.
• Purchase a battery-powered or hand-crank NOAA weather radio to receive emergency broadcasts when cellular networks fail.
• Establish a family emergency communication plan that does not rely on cellular networks. Designate an out-of-state contact as a central point of communication.

During the Attack: The First 10 Minutes

The initial blast wave and thermal pulse are your immediate threats. If you are caught outside when the detonation occurs, the following actions are critical. The FEMA Nuclear Detonation Planning Guide (2022) emphasizes that even a few minutes of decisive action can dramatically improve survival outcomes.

• Never look at the fireball. The thermal pulse can cause permanent blindness even at distances of several miles from the detonation point.
• Take cover behind anything that might offer protection from the blast wave — a wall, a vehicle, or a concrete barrier.
• Keep your mouth slightly open to prevent your eardrums from bursting due to the sudden pressure change caused by the blast wave.
• Once the shockwave passes, you have roughly 10 to 15 minutes before radioactive fallout begins to reach the ground. Use this time decisively to get inside a substantial building.

Choosing the Right Building

Not all buildings offer the same level of protection. The CDC's radiation emergency guidance ranks shelter effectiveness by building type. Underground concrete structures offer the highest protection factor, while wood-frame houses offer minimal shielding. When choosing a shelter, prioritize:

• Best: Underground basement of a multi-story concrete or brick building
• Good: Center of a large multi-story office building, away from windows
• Acceptable: Interior room of a brick or concrete single-story building
• Last resort: Interior room of a wood-frame house, away from windows

After the Attack: Surviving the Fallout

Fallout is the radioactive dust and ash that rains down after a nuclear explosion. It is highly lethal in the immediate hours after detonation but decays rapidly. The CDC's radiation emergency resources provide detailed guidance on post-blast decontamination and sheltering procedures.

• Strip off your outer layers of clothing before entering your clean shelter area. Removing clothing can eliminate up to 80% of radioactive contamination, according to the CDC.
• Wash your body with soap and water. Do not use hair conditioner, as it binds radioactive particles to your hair, making them harder to remove.
• Seal all windows, doors, and vents with heavy plastic sheeting and duct tape to prevent radioactive dust from entering your shelter.
• Consume only sealed, packaged food and bottled water. Do not use tap water, as it may be contaminated.
• Monitor emergency broadcasts on your hand-crank radio for official instructions from local authorities.

Radiation Basics: The 7:10 Rule of Radiation Decay

Understanding how radiation decays is your best defense against making a fatal mistake — leaving shelter too early. The most critical concept is the 7:10 Rule of Radiation Decay, which is used by FEMA and emergency planners worldwide.

This is why staying inside your shelter for the first 24 to 48 hours is absolutely mandatory. The rapid decay of fallout radiation means that patience is your most powerful survival tool.

Frequently Asked Questions

What will happen if there is a nuclear war?

A nuclear war would cause immediate, massive casualties in targeted areas due to the blast, thermal radiation, and initial ionizing radiation. This would be followed by widespread radioactive fallout, global supply chain collapse, failure of the electrical grid (EMP), and severe long-term environmental impacts, potentially including a "nuclear winter" that disrupts global agriculture for years. The IAEA's emergency preparedness resources provide detailed information on the long-term consequences of nuclear events.

What to do if WW3 breaks out?

If World War III begins, immediately execute your emergency survival plan. Relocate away from primary targets — military bases, major cities, and infrastructure hubs — if time permits. Secure your fallout shelter, ensure your stockpile of food, water, and medical supplies is accessible, and monitor emergency broadcast systems via a hand-crank radio. Stay off cellular networks to preserve bandwidth for emergency services.

Which countries have nuclear weapons?

Nine countries are currently known or widely believed to possess nuclear weapons: the United States, Russia, China, France, the United Kingdom, Pakistan, India, Israel, and North Korea. The US and Russia hold the vast majority of the global nuclear arsenal, with each possessing thousands of warheads.

Which countries will survive WW3?

Countries in the Southern Hemisphere — such as New Zealand, Australia, Argentina, and Chile — are statistically more likely to survive the direct impacts of a large-scale nuclear exchange. They are far from primary nuclear targets and are less likely to be severely affected by the immediate atmospheric spread of heavy nuclear fallout, though they would still face severe global economic and climatic consequences.