- 1). Push a heavy table that you can sit under against the wall of your basement that has the highest level of earth outside. The earth should be several feet above the top of the table top. Doors can also be used, if a table isn't available; use supports on either side, like stacks of books or side tables. Support your table with whatever material is available to prevent a collapse.
- 2). Pile any mass available on and on the sides of your table, including books, wood, bricks, sandbags, pillowcases or boxes full of earth, food and water supplies, heavy furniture, or any other heavy, dense mass. The more you add, the better protection you'll have.
- 3). Leave a small area to crawl out of your shelter with mass that acts as a door which you can easily pull in and out, and leave an area above this mass to act as an exhaust. A space four to six inches square left at the base will pull in fresh air.
- 4). Seal any vents in the basement to prevent radioactive particles from breaching your shelter. You can add mass to the floor above you, and to the outside wall of your basement, to add additional coverage. Keep a stock of water and food that will last two weeks for every member of the household.
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