46 U.S. Code § 5110 - Submersible vessels
Notwithstanding sections 5103–5105 of this title, the Secretary may prescribe regulations for submersible vessels to provide a minimum level of safety. In developing the regulations, the Secretary shall consider factors relevant to submersible vessels, including the structure, stability, and watertight integrity of those vessels.
Revised section 5110
Section 5110 authorizes the Secretary to prescribe regulations for the marking of load lines of submersible vessels. This general authority has been included in anticipation of the commercial development of submersibles.