PURPOSE: To obtain a satisfactory electromagnetically shielding characteristic while the lower frame part of a door frame is made to be flush with a floor.

CONSTITUTION: A door press contact mechanism 30 is mounted on a door body 11, and a door elevating mechanism is incorporated in an upper crane hinge 2. Further, shield packings 12, 12... are laid at the outer peripheral part of the rear side and the floor side end surface of the door body 11. The door body 11 is made into close contact with the front surface of the door frame 40 by means of the door press contact mechanism 30, and further, the floor side end surface thereof is made into close contact with the lower frame part of a door frame 40.