2.12.3 Hoistway Door Combination Mechanical Locks and Electric Contacts
(a) the top terminal landing and the landing whose sill is located not more than 1 225 mm (48 in.) below the top terminal landing sill, provided that the elevator rise does not exceed 4 570 mm (15 ft)
(a) for vertically sliding counterweighted doors, when the leading edge of the door is within 10 mm (0.375 in.) of the sill for doors that slide up to open, or 10 mm (0.375 in.) of the lintel for doors that slide down to open
(b) for vertically sliding biparting counterbalanced doors, when the astragal on the upper panel is within 19 mm (0.75 in.) of the lower panel
(c) when bypass switch is activated (see 22.214.171.124)
They shall be so installed and adjusted that the electric contact cannot close until the door is in the closed position as specified in 126.96.36.199, and so that the locking member is in a position to lock the door when or before the contact closes. In order to prevent motion of the door from opening the electric contact while the door is locked in the closed position, multiple-locking points shall, where necessary, be provided on the locking mechanism.
(a) They shall lock all panels of the door, but shall be permitted to be applied to only one section of the door, provided the device used to interconnect the door sections is so arranged that locking one panel will prevent the opening of all panels.
(b) Where used with vertically sliding biparting counterbalanced doors, the electric contact shall be so arranged that it is mechanically held in the open position by the door or a device attached thereto, unless the door is in the closed position.