How to survive a nuclear bomb: 3 steps to save you in case of a missile or attack by North Korea
War with North Korea seems unlikely, but the threat of a nuclear weapon detonation in the United States is nonzero. Here is how to stay alive in the worst case scenario. KREML/Shutterstock

How likely is the threat of nuclear war? Despite escalating tensions with North Korea, some experts say fears are overblown. Others caution that the United States is sleepwalking toward a conflict that could involve intercontinental ballistic missiles and, yes, nuclear weapons.

For the purposes of this story, likelihood isn’t the point: Being prepared for any devastating event — by buying insurance, saving cash in an emergency fund or simply keeping a first-aid kit around — is first and foremost about limiting risk. No matter how unlikely the worst case scenario, if the risk is greater than zero, you get informed, make a plan and line up preparations.

Despite an initial posting by the Centers for Disease Control announcing it would host a Jan. 16 event to help individuals and local authorities prepare for an unexpected nuclear attack — called Public Health Response to a Nuclear Detonation, a type of workshop the CDC last provided in 2010, according to the New York Times — the CDC canceled the event on Friday, replacing it with a session about influenza.

“While a nuclear detonation is unlikely, it would have devastating results and there would be limited time to take critical protection steps,” the CDC warned in its original release. “Despite the fear surrounding such an event, planning and preparation can lessen deaths and illness. For instance, most people don’t realize that sheltering in place for at least 24 hours is crucial to saving lives and reducing exposure to radiation.”

One reminder of the importance of preparedness emerged Jan. 13, when an emergency alert was sent out to phones of Hawaii residents — a message that was actually a false alarm, as Hawaii Rep. Tulsi Gabbard tweeted. The message read: “BALLISTIC MISSILE THREAT INBOUND TO HAWAII. SEEK IMMEDIATE SHELTER. THIS IS NOT A DRILL.” Though it was sent mistakenly, many Hawaii residents spent more than 30 minutes in fear that the alert was real, some regretting they had not prepared an emergency kit or “go bag.”

Others agree that — no matter what — basic readiness is invaluable: “With some very simple public messaging, we could save hundreds of thousands of lives in a nuclear detonation,” Irwin Redlener, director of Columbia University’s National Center for Disaster Preparedness, told NBC.

What can you do personally to get ready? These three steps can help you carefully and soberly prepare for one of the worst scenarios imaginable.

1. Nuclear shelter: Find a nearby place to shelter from the bomb or fallout

The last thing you want is to be Googling “nuclear shelters near me” when you’ve got mere minutes to seek out protection. The flight time of a launched North Korean nuclear missile might range from less than 20 minutes to more than 40, depending on which U.S. city is targeted, physicist David Wright estimated in an interview with Business Insider. So it is possible you might have only a few minutes of actual warning that an attack is underway.

Therefore a key preparatory step is having a plan ready now for exactly where you could go — perhaps near or in your home, your office or a location along your commute — if you were to hear of an imminent attack.

The more durable a shelter you can choose, the better, ideally one with a thick, dense roof and walls, according to the nuclear blast page of Ready.gov, an emergency preparedness website from the Department of Homeland Security. While “a direct hit from a nuclear explosion” will destroy even the strongest hideout — including “blast shelters” built to protect against “pressure, initial radiation, heat and fire” — if you survive the blast, you can then get by in a fallout shelter, a protected space that’s tough enough to “absorb the radiation given off by fallout particles.”

You are best off deep underground, surrounded by brick, concrete and earth, or at least in the centermost part of the structure, according to a guide shared by the Federal Emergency Management Agency.

The safest place to be, in case of a nuclear attack, is deep underground, surrounded by concrete or brick.
The safest place to be, in case of a nuclear attack, is deep underground, surrounded by concrete or brick. FEMA

You definitely don’t want to be hiding out in a car, Brooke Buddemeier, a certified health physicist at Lawrence Livermore National Laboratory, told Vice, as gamma radiation can come through the windshield and thin metal.

Don’t assume any fallout shelter signs you see on buildings are up to date: Many are obsolete. Instead, go to the website or offices of your town, city or municipal government to find out if any public buildings still qualify — or if there’s, say, a cavernous salt mine nearby you didn’t know about. It also never hurts to talk to your neighbors.

Of course, you might find there is not a good option near your home or work — or you might be caught in an unfamiliar place during an attack. In that case, do your best to seek refuge with the densest walls possible. If you’re on a beach, search for a cave — and if you are unlucky enough to be outside with no shelter in sight, “lie face down on the ground and protect exposed skin (i.e., place hands under the body), and remain flat until the heat and shock waves have passed. ... Cover the mouth and nose with a cloth to filter particulates from the inhaled air,” according to a DHS fact sheet. Don’t look at the flash or fireball, which can blind you.

What do you do if you are closest to a poor-quality shelter, but there is a better option farther away?

If the best shelter is nearby (less than 5 minutes away), “individuals should proceed to the adequate shelter and forgo sheltering in immediately available, poor-quality shelters,” according to a 2014 study published in Proceedings of the Royal Society A. But if the more adequate shelter is farther — between 5 and 15 minutes away — you might be better off staying briefly at the poor-quality shelter, and then heading “to the adequate-quality shelter no later than 30 [minutes] after the detonation,” the study found.

If you own your home and have a bit of land, you might consider building an underground shelter. It’s possible to buy a manufactured one to order if you have tens or hundreds of thousands of dollars to spare, but if you don’t — here and here and here are guides to DIYing one on a budget.

Finally, can you survive a nuclear bomb in a fridge, like Indiana Jones did in Indiana Jones and the Kingdom of the Crystal Skull? Almost definitely no — you would not live to tell the tale, according to one molecular biologist who investigated the matter.

2. Nuclear attack survival kit: Prepare your water, food and other supplies

Assuming you are far enough from the source of a nuclear detonation and find adequate shelter fast enough, you could survive the initial blast. Then your next step will be to stay alive despite radioactive nuclear fallout, which likely means sheltering in place.

The first few hours, days and weeks are most critical. Radioactivity in fallout decays rapidly, according to the State Department: “After seven hours, fallout has lost about 90% of the strength it had one hour after the explosion. After two days it has lost 99%; in two weeks 99.9%. ... Nevertheless, if the radiation at the beginning were high enough, the remaining 0.1% could be dangerous. Ideally, plan to stay in the shelter until radiation has been measured and the appropriate authorities have announced that it is safe to come out.”

That’s why keeping a supply kit or go bag at home could help you survive in that aftermath of the attack — and there’s no downside to preparing a kit right away. It could prove useful during or after other emergencies and natural disasters, such as snowstorms, fires or hurricanes.

What should you stock up on? According to Ready.gov, one gallon of water (bottled or otherwise sealed) per person per day; nonperishable food that’s sealed; a battery-powered or hand-crank radio and a NOAA weather radio with a tone alert; flashlight; first-aid kit; extra batteries; whistle; dust mask; plastic sheeting and duct tape; moist towelettes; garbage bags and plastic ties; a wrench or pliers; manual can opener; local maps; and a cell phone with chargers and a backup battery.

Here is a FEMA fact sheet with additional supplies — including prescription medications; a first-aid book; a warm blanket for each person; household chlorine bleach and medicine dropper; a fire extinguisher; matches; and feminine supplies — listed. You’ll want enough stuff for three days at a minimum, but ideally, enough for two weeks.

Source: FEMA

Here are some specific dos and don’ts regarding the food you keep in your kit, according to Ready.gov, including discarding any food that comes into contact with contaminated flood water.

Now, all of the supplies described so far are those you’d find in any standard emergency kit. Is there anything to have that is specific to a nuclear attack?

For one, “reverse-osmosis water filtration systems,” which you can easily buy online, “will remove fallout contamination,” according to the State Department.

Another basic supply that has seen demand surge recently: potassium iodide, which helps protect against certain types of radiation poisoning, according to a CDC webinar from August 2017. Unfortunately, in the case of a detonation, it might not help you much, the State Department website says.

Source: CDC

“Antidotes such as potassium iodide (KI) are [not] helpful in a nuclear detonation. KI is useful in response to a nuclear reactor mishap, where radioactive iodine release is a hazard. Radioactive iodine is not significantly present after a nuclear detonation, so KI is not useful in these circumstances,” the site warns.

3. Nuclear fallout radius and EMP: Learn rules for sheltering and staying alive

The blast from fission-driven atomic bombs, like those dropped over Nagasaki, Japan, and Hiroshima, Japan, during World War II, could kill everyone in a one-mile radius, Edward Morse, a nuclear engineering professor at the University of California, Berkeley, told Time. Yet a fusion-driven thermonuclear or hydrogen bomb radius could be more like 5 or 10 miles, Morse said. And beyond the immediate fireball and direct radiation, local winds could blow radioactive fallout to locations hundreds of miles away, according to Ready.gov.

That’s why sheltering in place is so important for those who survive the initial blast. Once you enter your shelter, you’ll want to close your space off and decontaminate to minimize exposure to fallout. Make sure windows, doors, fireplaces, air conditioners and other air access points are sealed off.

Gingerly shed your outermost layer of clothing, which “can remove up to 90% of radioactive material,” according to a CDC guide. “Be very careful in removing your clothing to prevent radioactive dust from shaking loose. Put the clothing in a plastic bag or other sealable container. Put the bag in an out-of-the-way place, away from other people and pets.”

Then gently wash off, keeping wounds covered, and using soap and shampoo but not conditioner — which can bind radioactive particles to your hair.

Source: CDC

If you can’t take a shower, according to the CDC, wash your hands, face and any uncovered parts of your body at a sink or faucet. “Use soap and plenty of water. If you do not have access to a sink or faucet, use a moist wipe, clean wet cloth or a damp paper towel to wipe the parts of your body that were uncovered. Pay special attention to your hands and face. Gently blow your nose, wipe your eyelids, eyelashes, and ears with a moist wipe, clean wet cloth, or a damp paper towel.”

Disposing of contaminated items is crucial, the CDC warns: “Put the used wipes, cloth or towel in a plastic bag or other sealable container and place the bag in an out-of-the-way place, away from other people and pets.”

Finally, as you shelter in place, the CDC suggests you “stay tuned,” using the battery-powered or hand crank emergency radio (preferably a NOAA weather radio) in your emergency kit. “Depending on the size and scope of the radiation emergency, it may be difficult to complete a phone call,” according to the CDC, so “try to use text messages (SMS)” or “email, social media websites (like CDC Facebook page and CDC Emergency Twitter feed).” Whatever you do, “do not go outside to reset breakers.”

Be prepared for the possibility of lost communication: “The ionization of the atmosphere around the blast can result in an electromagnetic pulse (EMP) that, for ground detonations, can drive an electric current through underground wires causing local damage,” the DHS warns. “For high-altitude nuclear detonations, EMP can cause widespread disruption to electronic equipment and networks.”

Lost communication — paired with injuries or a lack of sufficient food and water — could mean you’re forced to make tough decisions about leaving shelter before the recommended two weeks is up. The degree to which you need to worry about exposure to fallout outside depends on the radius of the blast — and that depends on the type of nuclear bomb used.

There’s evidence Kim Jung Un’s regime has already developed missile technology that could reach as far as the east coast of the United States, the New York Times has reported, and that North Korea has successfully tested a hydrogen weapon with 15 times the explosive force of the atomic bomb used in the attack on Hiroshima.

If you want to get a sense of how your hometown or city would fare — given the radius width of several different types of nuclear blasts — Stevens Institute of Technology science historian Alex Wellerstein created an interactive browser tool called NUKEMAP, which overlays hypothetical bombs on Google Maps. “People tend to have either wildly exaggerated views of the weapons, or wildly under-appreciate their power,” Wellerstein told Business Insider.

This hypothetical scenario involves a 150 kiloton weapon with a surface detonation at Times Square in New York City. The arrow shows the direction wind could blow radioactive fallout.
This hypothetical scenario involves a 150 kiloton weapon with a surface detonation at Times Square in New York City. The arrow shows the direction wind could blow radioactive fallout. Alex Wellerstein/NUKEMAP

Testing out Wellerstein’s tool, this reporter “detonated” a 150 kiloton weapon — one estimate of the bomb North Korea may have (though other estimates are higher) — in New York City: According to NUKEMAP, total fatalities would exceed 820,000 and nearly 700,000 would be injured. Yet, as you can see in the image above, it is possible for those living far enough from the ground zero blast area to escape the very worst destruction.

Here is a key to help understand the map above.
Here is a key to help understand the map above. Alex Wellerstein/NUKEMAP

As frightening as this all is, you are best off avoiding fatalism and focusing on your chances of survival. As Japanese doctor and atom bomb survivor Shuntaro Hida told Vice at age 95 in 2008, “I got out of Hiroshima just in time to be saved from being directly hit. I was exposed to the radiation, but from a distance of just over three miles from the epicenter.”

Similarly, several Nagasaki and Hiroshima survivors who shared stories published by Time have reached their 70s, 80s and 90s, despite suffering the effects of radiation exposure.

One man, Takato Michishita, described how his mother saved him and his sister by suggesting they stay home from school: “My mother and I, aged 6, went grocery shopping. ... Suddenly, an old man yelled ‘Plane!’ ... My mother and I escaped into a nearby shop. ... [S]he quickly tore off the tatami flooring, tucked me under it and hovered over me on all fours. Everything turned white. We were too stunned to move, for about 10 minutes. When we finally crawled out from under the tatami mat, there was glass everywhere, and tiny bits of dust and debris floating in the air. ... We rushed home and found my sister — she was shell-shocked, but fine.”

Further reading on surviving a nuclear war or attack

• CDC guide to surviving a radiation emergency
• EPA radiation protection landing page
• Department of State guide to surviving radiological nuclear incidents
• A 2010 federal planning guide to nuclear detonation response
• Guam Homeland Security fact sheet
• A 1987 nuclear war survival skills guide
• A 1961 Department of Defense guide to fallout protection

Feb. 26, 2017, 10:30 a.m. Eastern: This story has been updated.