http://www.survivalring.org/Bhfs1.jpg
http://www.survivalring.org/shelters/belowground-fallout-shelter/
BELOWGROUND FALLOUT SHELTER
The plan on this page is for a fallout shelter constructed BELOW ground, giving you more protection from fallout radiation than on open ground. The data (...) can be found on my SHELTER PLANS page, as well as Robin’s website at www.bwolf.com . Thanks, Robin.
This family fallout shelter, designed primarily for homes without basements, is a permanent home shelter to be placed in the yard. It is designed to have a protection factor of at least 40, which is the minimum standard of protection for public shelters throughout the United States.
This assures that persons inside the shelter will be protected against radioactive fallout following a nuclear attack, and will also have protection against earthquakes, hurricanes and tornadoes.
Following are detail drawings of the shelter, which is capable of housing six adults.
It can be built of poured reinforced concrete, precast concrete slabs, or a combination of concrete blocks and poured concrete. If it is built as detailed with the top near ground level, the roof slab can be used as an outdoor patio.
The shelter is accessible by a hatch-door and wood stairway. Fresh air is provided by a hand-operated centrifugal blower and two ventilating pipes that extend above ground level.
In areas where there is poor drainage or where the ground water table is close to the surface, the fourth modification on page 5 should be used.
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