46 CFR § 172.105
Extent of damage
April 15, 2021
For the purpose of §172.103, design calculations must include both side and bottom damage, applied separately. Damage must consist of the most disabling penetration up to and including penetrations having the following dimensions:
(a) Side damage must be assumed to be as follows:
(1) Longitudinal extent—6 feet (183 centimeters).
(2) Transverse extent—30 inches (76 centimeters).
(3) Vertical extent—from the baseline upward without limit.
(b) Bottom damage must be assumed to be 15 inches (38 centimeters) from the baseline upward.