How to Build a Nuclear Fallout Shelter

If you dug a hole in your yard and

jumped in when the bomb falls,

you'd have a nuclear shelter.

But the blast wave would collapse the walls above

your head. So you lower a huge

steel pipe and bury it under 90

centimeters of dirt.

But the blast sucks the dirt upward into a mushroom

cloud.

Then it falls back down as radioactive rain.

This is called nuclear fallout.

Every nine centimeters of dirt cuts radiation in half.

So 90 centimeters blocks 99.9 percent of it.

But radiation travels

in a straight line and

comes straight in through the entrance.

So you bend the tunnel twice.

The rays hit the dirt instead of hitting you.

But ten people in a place without

ventilation make the place stuffy in

a few hours. So you run an air

pipe upward with a dust filter

and a fan you turn by hand.

But the next blast wave rushes in through the same

pipe. So you install a valve that

closes in three thousandths of a

second. This is called a blast valve.

But the blast hits your door like a truck.

So you make it open

outward. Then the blast only

presses it harder against

its frame.

This is called a blast door.

But debris can pile up against it.

And trap you inside.

So dig another tunnel leading

to the emergency hatch above.

But radiation is invisible.

So you don't know when it's safe.

So hang a meter that clicks whenever radiation hits it.

This is called a Geiger counter.

Most people think you'll be down there

for years. No, you won't.

Nuclear fallout becomes ten times weaker

after seven hours,

and 100 times weaker after two days.

So you only need supplies for

two weeks. Put in bunk beds,

canned food, and a hand- cranked radio.

Congratulations, you've built a nuclear shelter.