§ 27-516 Pressurization system.
AC § 27-516
Air-supported structures shall be inflated and shall remain inflated during all periods of occupancy to a minimum differential pressure of 0.88 in. and a maximum differential pressure of 1.50 in. of water. Ventilation flow per occupant, either through vents or anticipated leakage, shall comply with the requirements of subchapter twelve of this chapter. Occupied spaces. Where the net floor area per occupant is one hundred fifty square feet or less, the structure shall be provided with at least two blowers, each of which shall have adequate capacity to maintain the required inflation pressure. Also, an auxiliary engine-generator set capable of powering one blower, or a supplementary blower powered by an internal combustion engine, either of which shall have the capacity to run continuously for four hours, shall be located outside the structure, shall be weather protected, and shall be arranged to automatically operate the blower within twenty seconds upon failure of the normal source. Heat shall be provided from a source outside the structure so arranged as to prevent the spread of fire to the structure. The temperature within the air-supported structure shall be maintained at the temperature required by subchapter twelve of this chapter, but not less than fifty degrees Fahrenheit during periods of snowfall.
