N.Y. LAB Law § 267

§ 267. Horizontal exit. 1. "Horizontal exit" means the connection by\none or more openings, protected by firedoors, through a fire wall in any\nbuilding, or through a wall or walls between two buildings, which doors\nshall continuously be unlocked and the opening unobstructed whenever any\nperson is employed on either side of the opening.\n 2. Exterior balconies and bridges not less than forty-four inches in\nwidth connecting two buildings and not having a gradient of more than\none foot fall in six, may also be counted as horizontal exits when the\ndoors opening out upon said balconies or bridges are fireproof doors and\nare level with the floors of the building, and when all doors of both\nbuildings opening on such balconies or bridges are continuously kept\nunlocked and unobstructed whenever any person is employed on either side\nof the exit, and when such balconies or bridges are built of\nincombustible material and are capable of sustaining a live load of not\nless than ninety pounds per square foot with a factor of safety of four;\nand when such balconies or bridges are enclosed on all sides to a height\nof not less than six feet and on top and bottom by fireproof material,\nunless all windows or openings within thirty feet of such balconies in\nthe connected buildings shall be encased in metal frames and sash and\nshall have wired glass where glass is used.\n 3. In any case there shall be on each side of the wall or partition\ncontaining the horizontal exit and independent of said horizontal exit,\nat least one stairway conforming to the requirements for a required\nexit.\n