Abstract: A circular door operating method and apparatus comprising two pairs of arcked door leaves, two pairs of arcked fixed panels arranged so as to form an enclosure defining a cylindrical wind blocking compartment. Each door leaf is hinged at an end and releasably coupled at the other end to a hanger assembly traveling on a circular track by means of a pulley mechanism. When a door leaf is released from the hanger assembly to pivot about upper and lower hinge mechanisms for operation as a hinged door, not only the upper and lower hinge mechanisms firmly support the door leaf in place but also a control unit disables the sliding door operation, thus providing a quick and safe escape from the building in the event of an emergency.