CFR > Title 46 - Shipping > CHAPTER I—COAST GUARD, DEPARTMENT OF HOMELAND SECURITY > SUBCHAPTER S—SUBDIVISION AND STABILITY (parts 170 to 174) > PART 174—SPECIAL RULES PERTAINING TO SPECIFIC VESSEL TYPES > SUBPART I—Hopper Dredges With Working Freeboard Assignments (§174.300 to §174.340) > 174.320—Damage survival.

174.320—Damage survival.

A hopper dredge survives assumed damage if it meets the following conditions:
(a) The maximum angle of heel in each stage of flooding must not exceed 30 degrees or the angle of downflooding whichever is less.
(b) The final waterline, taking into account sinkage, heel, and trim, must be below the lowest edge of each opening through which progressive flooding may take place.
(c) The righting arm curve calculated after damage must:
(1) Have a minimum positive range of 20 degrees beyond the angle of equilibrium; and
(2) Reach a height of at least 4 inches (l00mm) within the 20 degree positive range.
(d) Each opening within, or partially within, the 20 degree range beyond the angle of equilibrium must be weathertight.
(e) After flooding or equalization as allowed by § 174.325, the hopper dredge's metacentric height must be at least 2 inches (50mm) when the dredge is in an upright position.