Ordinance 4321 - Laserfiche WebLink

• • Pier decks of composite laminated timber end concrete construction shall be acceptable for a combustible substructure, provided that timbers used shall be not less than two inches in minimal thickness. Where railroad tracks or other depressions are run onto a pier and are at a lower level than the deck, the sides and bottom of the depressed section shall be of the same construction es the pier deck, or of equivalent fire resistance. Side hatches shall be permitted in the walls of such depressed section for fire fihtin.g purposes with openings normally closed by hatch covers having a fire resistance rating equivalent to the walls. C. Aprons. • Pier aprons or platforms built along the sides or ends of a pier of a combustible substructure shall have the substructure and deck constructed so as to have fire-resistive qualities equal to that of the pier substructure and deck, except that at every fire wall of the superstructure a section of the apron or platform and its substructure shall be of fire resistive construction equal to that of the fire wall in order to preserve the effect- iveness of the fire wall. The fire-resistive section shall extend for a distance of at least ten feet on each side of the fire wall. D. Automatic Sprinklers. A. complete system of automatic sprinklers shall be installed for the protection of all combustible substructures. Installation of sprinkler equipment shall be in accordance with the Standard for Installation of Sprinkler Systems (NEPA No. 13, 1968) and section No.. 14 of this ordinance. In those parts of waterfront structures where sprinkler piping or equipment may be subject to damage by floating debris such as beneath certain depressed sections of pier decks, the Chief of the Fire Department may permit deviations from the strict application of the Standard and may require alternative methods of protection. In any case where there is danger to sprinkler equipment by floating objects, suitable barriers shall be provided to exclude such objects by use of a fender system or by other suitable means. - In addition to the Standard for Lnstallation of Sprinkler System (NFPA No. 13, 1968) and section No. 14 of this ordinance, sprinkler systems shall meet the following requirements: I. Sprinkler systems in underdeck areas shall be properly protected throughout against corrosion. II. All sprinkler heads used in underdeck spaces shall be corro lon- resistant type. III. Water supply mains shall preferably be installed in the underdeck space, provided there is sufficient head space above high water level to maintain adequate frost protection. If it is inadvisable to install mains in underdeck space, they may be installed within the super- structure with adequate protection against frost and physical damage. IV. Rate-of-rise devices for the protection of substructures in con- junction with automatic sprinklers should be installed with due regard to maintenance and possibility of false alarms. Ordinance -4 • -