Code of Massachusetts Regulations
780 CMR - STATE BOARD OF BUILDING REGULATIONS AND STANDARDS
Chapter 4 - Special Detailed Requirements Based on Use and Occupancy
Section 412 - AIRCRAFT-RELATED OCCUPANCIES
Subsection 412.3 - Airport traffic control towers
Current through Register 1531, September 27, 2024
412.3.1 General. The provisions of Sections 412.3.1 through 412.3.6 shall apply to airport traffic control towers not exceeding 1,500 square feet (140 m2) per floor occupied only for the following uses:
412.3.2 Type of construction. Airport traffic control towers shall be constructed to comply with the height and area limitations of Table 412.3.2.
TABLE 412.3.2 HEIGHT AND AREA LIMITATIONS FOR AIRPORT TRAFFIC CONTROL TOWERS
TYPE OF CONSTRUCTION | HEIGHTa (feet) | MAXIMUM AREA (square feet) |
IA | Unlimited | 1,500 |
IB | 240 | 1,500 |
IIA | 100 | 1,500 |
IIB | 85 | 1,500 |
IIIA | 65 | 1,500 |
For SI: 1 foot = 304.8 mm, 1 square foot = 0.0929
m2. a. Height to be measured from grade plane to cab floor. |
412.3.3 Egress. A minimum of one exit stairway shall be permitted for airport traffic control towers of any height provided that the occupant load per floor does not exceed 15. The stairway shall conform to the requirements of Section 1009. The stairway shall be separated from elevators by a minimum distance of one-half of the diagonal of the area served measured in a straight line. The exit stairway and elevator hoistway are permitted to be located in the same shaft enclosure, provided they are separated from each other by a 4-hour fire barrier having no openings. Such stairway shall be pressurized to a minimum of 0.15 inch of water column (43 Pa) and a maximum of 0.35 inch of water column (101 Pa) in the shaft relative to the building with stairway doors closed. Stairways need not extend to the roof as specified in Section 1009.11. The provisions of Section 403 do not apply.
Exception: Smokeproof enclosures as set forth in Section 1022.9 are not required where required stairways are pressurized.
412.3.4 Automatic fire detection systems. Airport traffic control towers shall be provided with an automatic fire detection system installed in accordance with Section 907.2. [F]
412.3.5 Standby power. A standby power system that conforms to Chapter 27 shall be provided in airport traffic control towers more than 65 feet (19 812 mm) in height. Power shall be provided to the following equipment: [F]
412.3.6 Accessibility. Airport traffic control towers need not be accessible as specified in the provisions of Chapter 11.