46 C.F.R. § 108.429 Fire main system protection.
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(a) Each pipe and fire hydrant in a fire main system must be installed to the extent practicable in locations that are not exposed to damage by materials that are moved on or onto the deck. (b) Each part of the fire main system located on an exposed deck must either be protected against freezing or be fitted with cutout valves and drain valves to shut off and drain the entire exposed system in freezing weather.
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PART 108—DESIGN AND EQUIPMENT
Subpart D—Fire Extinguishing Systems
Fire Main System
§ 108.429 Fire main system protection.