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(a) Mechanically operated.
(1) Cargo door counterweights shall be guarded.
(2) Lift trucks and cranes shall not be used to move mechanically operated doors except when necessary during repair on the doors, in which case ropes or other guarding shall be provided to prevent entry into the area where the door may fall or slide.
(3) Vertically operated doors partially opened for work or ventilation shall be secured to prevent accidental closing.
(b) Tackle operated.
(1) The door shall be connected to its lifting tackle with shackles or equally secure means.
(2) Lifting bridles and tackles shall have a safety factor of five, based upon maximum anticipated static loading conditions.
(3) Devices shall be provided to hold overhead doors in the open position and to secure them when closed.
(4) Lifting gear and hardware shall be maintained in safe condition.
(5) Lifting ropes, when used, shall be placed out of the work area and off the floor.
(c) Horizontal sliding.
(1) Horizontal sliding door rollers shall be constructed to prevent the door from jumping from overhead tracks.
(2) Sliding doors shall be secured to prevent them from swinging.