Section 3 Air, Sounding and Filling Pipes

301. Air pipes

1. All compartments and tanks arranged with filling and/or drainage arrangements are to have an air pipe.

2. All tanks containing flammable liquids, or which can be pumped up or filled from the sea, are to have air pipes extending above the weather deck.

3. Air pipes from fuel and lubricating oil systems are to be carried up to a position where water can- not enter, and be so arranged that vapor or overflow cannot be ignited.

4. All air pipes extending to exposed water may have access below of at

decks are to have a height from the deck to the point where least 300 mm where the deck is less than 0.05 L above the de-

sign waterline, and 150 mm on all other decks.

5. Air pipes for tanks not fitted with overflow pipes are to have a cross sectional area not less than 125 % of the filling pipes.

6. Air pipes may discharge through the side of the superstructure provided that this is at a height of at least 0.02 above any waterline when the intact craft is heeled to an angle of 15° or 0.02 L above the highest waterline at all stages of flooding as determined by the damaged stability calcu- lations, whichever is higher.

7. All air pipes are to be equipped with approved weathertight closing devices that close automatically.

302. Sounding and filling pipes

1. All compartments and tanks arranged with filling and/or drainage arrangements are to have means for ascertaining the level of liquid.

2. All tanks containing flammable liquids or which can be pumped up or filled from the sea are to have sounding pipe carried up to the open air fitted with screw cap or equivalent. Other approved level indicator or remote sounding arrangement may replace sounding pipe.

3. Filling pipes to tanks containing flammable liquids are to terminate on the weather deck and are to be so arranged that possible spill cannot escape to the inside of the vessel, but will be collected inside a suitable arranged coaming.

4. All filling pipes to fuel and lubricating oil tanks are to have screw caps, plugs or similar arrange- ment preventing water from entering such tanks.