Section 178.420 - Drainage of cockpit vessels(a) Except as follows, the cockpit on a cockpit vessel may be watertight: (1) A cockpit may have companionways if the companionway openings have watertight doors, or weathertight doors and coamings which meet § 179.360 of this subchapter.(2) A cockpit may have ventilation openings along its inner periphery if the vessel operates only on protected or partially protected waters.(b) The cockpit deck of a cockpit vessel that operates on exposed or partially protected waters must be at least 255 millimeters (10 inches) above the deepest load waterline unless the vessel complies with:(1) The intact stability requirements of §§ 170.170 , 170.173 , 171.050 , 171.055 , and 171.057 in subchapter S of this chapter;(2) The Type II subdivision requirements in §§ 171.070 , 171.072 , and 171.073 in subchapter S of this chapter; and(3) The damage stability requirements in § 171.080 in subchapter S of this chapter.(c) The cockpit deck of a cockpit vessel that does not operate on exposed or partially protected waters must be located as high above the deepest load waterline as practicable.(d) The cockpit must be self-bailing. Scuppers or freeing ports for the cockpit deck of a cockpit vessel must:(1) Be located to allow rapid clearing of water in all probable conditions of list and trim;(2) Have a combined drainage area of at least the area required by § 178.450 of this part; and(3) If the deck is less than 255 millimeters (10 inches) above the deepest load waterline of the vessel, be fitted with non-return devices.