Nuclear detonation and fallout

The first hour

If you see a flash, don't look at it. Lie flat, cover your head, and take cover behind anything solid.
Get inside the nearest sturdy building right away. Brick or concrete is best. Cars and mobile homes are not good shelter.
Go to the basement or the middle of the building, away from outside walls and the roof.
Fallout often takes 15 minutes or more to reach the ground outside the blast zone. Use that time to get inside.
If you were outside: take off your outer layer of clothing (this can remove up to 90% of radioactive material). Bag it and set it far from people.
Shower with soap and water if you can. Don't scrub hard. Use shampoo or soap on hair, but no conditioner; it binds radioactive material to hair. If no shower, wipe skin with a wet cloth.

Stay inside for at least 24 hours unless officials tell you otherwise.
Stay where you are, even if family is apart. Reunite later, when it's safe. Leaving shelter early is the bigger risk.
Keep pets inside. Listen to a battery or hand-crank radio.
Eat and drink only things that were sealed or inside. Don't drink tap water until told it's safe.
Protection comes from three things: time (less time exposed), distance (farther from fallout), shielding (more dense material between you and it).

KI (potassium iodide) only protects the thyroid, and only from radioactive iodine. It does not protect the rest of your body or from most fallout.
CDC: after a nuclear detonation, KI won't protect you from fallout's outside radiation, which is the biggest threat. Don't leave shelter to look for KI.
Take KI only when public health or emergency officials tell you to. One dose protects for about 24 hours.
Most important for people under 40, pregnant and breastfeeding women. Adults over 40 only if officials advise.
Table salt, iodine-rich foods and non-FDA iodine supplements are not substitutes. Taking too much can be dangerous.

Know shelter spots at home, work and school (basement or center of a brick/concrete building)
Battery or hand-crank radio
Water and food for at least 24 to 72 hours where you'd shelter
Plastic bags for clothing
Wet wipes
Medicines
Family plan that says 'stay put and reunite later'

Your checks save on this phone.

Tell kids: 'We're going to stay inside together until the helpers tell us it's safe.'
Bring activities into the shelter area.
Kids at school will be sheltered there. Don't try to get them.

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