VENTILATORS, AIR AND SOUNDING PIPES

Ventilators are necessary to give adequate air circulation to under deck spaces, accommodation and tanks. The coamings of ventilators are to have a minimum height above the weather deck of 900 mm in Position 1 and 760 mm in Position 2 Where the coamings exceed 900 mm in height they are to be specially stayed.

All ventilators are to be provided with means of closing unless the height of the coaming exceeds 4.5 m in Position 1 and 2.3 m in Position 2.

Special care is to be taken when designing and positioning ventilator openings, particularly in regions of high stress concentration.

Mushroom, gooseneck and other minor ventilators are to be strongly constructed and efficiently secured to the deck.

Goose or swan neck type ventilators are mainly used for air pipes to tanks. The height (H) shown is not to be less than 760 mm on the freeboard deck and 450 mm on the superstructure deck. Air pipes are to be fitted at the opposite end of the tank to that at which the filling pipe is placed and/or at the highest point of the tank.

Sounding pipes are to be as straight as possible and to have a bore not less than 32 mm. Where a sounding pipe passes through a refrigerated compartment where temperatures may be 0°C or below the bore is not to be less than 65 mm. Striking plates of adequate thickness and size are to be fitted under open-ended sounding pipes.