A sufficient serviceable fire hose with a suitable nozzle attached to reach all parts of the vessel shall be connected to the fire main on the vessel and made ready for immediate use at all times the vessel is at a wharf. If adequate water pressure is not available on board ship, connections shall be made to shore lines to obtain adequate pressure. All outlets or shore connections shall be provided with approved anti- contamination or backflow preventing devices acceptable to the Los Angeles Department of Water and Power.