33 CFR 401.3 - Maximum vessel dimensions.
(a) Subject to paragraph (e) of this section, no vessel of more than 222.5 m in overall length or 23.8 m in extreme breadth shall transit.
(b) No vessel shall transit if any part of the vessel or anything on the vessel extends more than 35.5 m above water level.
(c) No vessel shall transit if any part of its bridges or anything on the vessel protrudes beyond the hull.
(d) No vessel's hull or superstructure when alongside a lock wall shall extend beyond the limits of the lock wall, as illustrated in appendix I of this part.
(e) A vessel having a beam width in excess of 23.2 m, but not more than 23.8 m, and having dimensions that do not exceed the limits set out in the block diagram in appendix I of this part or overall length in excess of 222.5 m, but not more than 225.5 m, shall, on application to the Manager or Corporation, be considered for transit in accordance with directions issued by the Manager and Corporation.
(f) Vessels with beams greater than 23.20 m may be subject to transit restrictions and/or delays during periods of ice cover.