There are many parts of the world that are periodically exposed to storms, tornadoes and other severe wind conditions. Conventional aboveground safety shelters are either built belowground or depend almost completely upon attachment to a concrete foundation or ground anchors to resist movement. To resist wind induced overturning, uplift and sliding, such concrete foundations are generally comprised of expensive subterranean concrete footings. Some conventional metal shelters can be unbolted from their heavy concrete foundations for movement to a new location; however, each new location requires the preparation of another heavy concrete foundation to which the shelter can be bolted. In most instances the cost and inconvenience of pouring of a new foundation (and the attendant environmental impact of their subsequent demolition and removal) renders impracticable the redeployment of a metal protective shelter for temporary use.
USPTO Backgrounds
USPTO Backgrounds