t wall is above ground
level, this plan should _not_ be used unless you add the "optional
walls" shown in the sketch.

Overhead protection is obtained by screwing plywood sheets securely to
the joists, and then filling the spaces between the joists with bricks
or concrete blocks. An extra beam and a screwjack column may be needed
to support the extra weight.

Building this shelter requires some basic woodworking skills and about
$150-$200 for materials. It can be set up while the house is being
built, or afterward.

ALTERNATE CEILING MODIFICATION PLAN B

This is similar to Plan A, except that new extra joists are fitted into
part of the basement ceiling to support the added weight of the
shielding (instead of using a beam and a screwjack column).

The new wooden joists are cut to length and notched at the ends, then
installed between the existing joists.

After plywood panels are screwed securely to the joists, bricks or
concrete blocks are then packed tightly into the spaces between the
joists. The bricks or blocks, as well as the joists themselves, will
reduce the amount of fallout radiation penetrating downward into the
basement.

Approximately one-quarter of the total basement ceiling should be
reinforced with extra joists and shielding material.

_Important:_ This plan (like Plan A) should _not_ be used if 12 inches
or more of your basement wall is above ground level, unless you add the
"optional walls" inside your basement that are shown in the Plan A
sketch.

PERMANENT CONCRETE BLOCK OR BRICK SHELTER PLAN C

This shelter will provide excellent protection, and can be constructed
easily at a cost of $150 in most parts of the country.

Made of concrete blocks or bricks, the shelter should be located in the
corner of your basement that is most below ground level. It can be built
low, to serve as a "sitdown" shelter; or by making it higher you can
have a shelter in which people can stand erect.

The shelter ceiling, however, should _not_ be higher than the outside
ground level of the basement corner where the shelter is located.

The higher your basement is above ground level, the thicker you should
make the walls and roof of this shelter, since your regular basement
walls will provide only limited shielding against outside radiation.

Natural ventilation is provided by the shelter entrance, and by the air
vents shown in the shelter wall.

This shelter can be used as a storage room or for other