46 CFR § 42.20-20
Correction to the freeboard for vessels under 328 feet in length
April 15, 2021
(a) The tabular freeboard for a Type “B” vessel of between 79 feet and 328 feet in length having enclosed superstructures with an effective length of up to 35 percent of the length of the vessel shall be increased by:
0.09 (328−L) [0.35−(E/L)] inches
where:
L = length of vessel in feet.
E = effective length of superstructure in feet as defined in §42.20-50.
[CGFR 68-60, 33 FR 10064, July 12, 1968]