Tornado borne missile

This 3-ft thick concrete door is approximately 25 -5"( 7.8 m) wide and 24 -6" (7.47 m) high. It is located at the equipment hatch in the primary containment at the 270° azimuth. The basic function of the door is to provide radiation and tornado borne missile shielding for the equipment hatch opening. 

This door shall be designed to withstand the stresses produced by the credible tornado-borne missiles listed in the General Criteria for Design of Civil Structures, N14-50-D702. For further design considerations by others see Shield Door at Equipment Access Hatch Criteria, N4-MAD740C. 

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