505.2.3 Openness.
BC § 505.2.3
A mezzanine shall be open and unobstructed to the room in which such mezzanine is located except for walls or railings not more than 42 inches (1067 mm) in height, columns and posts. Exceptions: 1. Mezzanines or portions thereof are not required to be open to the room in which the mezzanines are located, provided that the occupant load of the aggregate area of the enclosed space is not greater than 10.
2.A mezzanine having two or more means of egress is not required to be open to the room in which the mezzanine is located, if at least one of the means of egress provides direct access to an exit located on the mezzanine level.
3.Mezzanines or portions thereof are not required to be open to the room in which the mezzanines are located, provided that the aggregate floor area of the enclosed space is not greater than 10 percent of the mezzanine area.
4.In industrial facilities, mezzanines used for control equipment are permitted to be glazed on all sides.
5.A mezzanine having two or more means of egress shall not be required to be open to the room in which the mezzanine is located in occupancies, other than Groups H and I, that comply with Items 5.1 through 5.4. 5.1. Such occupancy is no more than two stories above grade plane, 5.2. Such occupancy is equipped throughout with an automatic sprinkler system in accordance with Section 903.3.1.1, 5.3. An approved fire alarm system is installed throughout the entire building or structure in which such occupancy is located, and 5.4. Notification appliances are installed throughout the mezzanine in accordance with NFPA 72. (Am. L.L. 2023/077, 6/11/2023, eff. 6/11/2023) Editor's note: For related unconsolidated provisions, see Appendix A at L.L. 2023/077.
