1224.4.9 Windows and Screens
Rooms approved for the housing of patients shall be provided with natural light by means of exterior glazed openings excluding clerestory windows, obscure glass and skylights, with an area not less than one tenth of the total floor area.
Patient room windows shall have sills not more than 36 inches (914 mm) above the floor. If operable windows are provided that require the use of tools or keys for operation, the tools or keys shall be located at the nurses' station.
Exception: Window sills in intensive-care units may be 60 inches (1524 mm) above the floor.
Safety glass or plastic glazing materials shall be used in windows in psychiatric patient areas.
Windows which may be frequently left in an open position shall be provided with insect screens of 16 meshes to the inch.