An Above-Ground Storm Shelter is designed to resist high winds, object impact, shifting foundations, flooding, and heavy rains. It's made either of thick steel plates that are bolted together or of pre-cast, steel-reinforced concrete. In some cases, the component parts are delivered to the site where a crew assembles the shelter then anchors it to an earlier-laid reinforced foundation slab. Manufacturers claim that such a structure can withstand even the most destructive category of tornado (EF5), which produces wind speeds greater than 200 miles per hour. The sources listed here say that their shelters are disability-accessible.