Section 148.1 - Purpose and applicability(a) This part prescribes special handling procedures for certain solid materials that present hazards when transported in bulk by vessel.(b) Except as noted in paragraph (c) of this section, this part applies to all domestic and foreign vessels in the navigable waters of the United States that transport bulk solid materials requiring special handling.(c) This part does not apply to an unmanned barge on a domestic voyage carrying a Potentially Dangerous Material (PDM) found in Table 148.10 of this part. All barges on international voyages must follow the requirements for PDM.(d) The regulations in this part have preemptive impact over State law on the same subject. The Coast Guard has determined, after considering the factors developed by the Supreme Court in U.S. v. Locke, 529 U.S. 89 (2000), that in directing the Secretary to regulate the safe transportation of hazardous material and the safety of individuals and property on board vessels subject to inspection, as well as the provision of loading information, Congress intended to preempt the field of safety standards for solid materials requiring special handling when transported in bulk on vessels.