Meteorologically speaking, hurricanes are long in duration with strong, sustained winds and rapid fluctuations in air pressure. Products designed for use in areas prone to hurricanes are subjected to tests that simulate storm conditions, including impact from airborne debris and cyclical pressure differentiation. A building designed to hurricane standards would be expected to survive the storm in good condition. Doors and hardware on the building envelope are expected to be operational after absorbing the abusive conditions.
Tornados, conversely, are short in duration with intense winds. Typically, a building in tornado prone areas might include one room as a designated storm shelter that would be built with appropriate shelter-grade products. The goal in a tornado is not necessarily to protect the building, but to ensure the survival of the occupants within. If a building is destroyed by a tornado, the designated shelter within the structure should remain standing if it is properly designed. Doors and hardware are not expected to be functional after enduring these conditions; they must simply remain intact.