15.100.670   Installation.
   An on-site emergency standby power generating system consisting of one or more approved generators for every highrise building shall be installed in one or more of the following locations:
   A.   Indoors. Every room or area in which a combustion engine or gas turbine is installed for generating standby and emergency power shall be separated from the remainder of the building by a minimum of two-hour fire resistive construction.
      1.   Openings. Windows, louvered openings and any other openings shall be located on exterior walls only. When such openings are located below openings in another story or less than ten (10) feet from any opening on the same building, they shall be protected by a fire assembly having a minimum of one and one-half hour fire resistive rating. Such fire assemblies shall be fixed, automatic or self-closing.
      2.   The generator shall not be located above the first floor.
      3.   The generator may be placed in an underground vault provided provisions are made to prevent flooding from surface and/or ground water. Drains within the vault shall be designed to prevent any backflow into the vault.
   Exception: Generators may be permitted in above ground parking structures with proper vehicle access.
   B.   Outdoors. When combustion engines and gas turbine generators are located outdoors, they shall be a minimum of ten (10) feet from the building and a minimum of ten (10) feet from the property.
   Exception: The distance from the building may be reduced to five feet where there are no openings on the building within ten (10) feet of the generator.
   C.   Generators shall be located for easy access of load bank test equipment.
   D.   Rooms or areas used for power generating systems shall not be used for any other purpose. Where locations are available to vehicle access, they shall be suitably protected.
   E.   Power-generating systems shall not be located within fifty (50) feet of the fire control room. (Prior code §§ 9.28.1266, 15.15.1501)