The four modes of transportation that are covered under the Hazardous Materials Regulations, including the registration requirement, are highway, rail, air, and water. Highway transportation includes all interstate, intrastate, and foreign shipments that meet the registration criteria and are not specifically excepted by regulation. Water transportation does not include hazardous materials loaded or carried on board a vessel without benefit of containers or labels and received and handled by the vessel carrier without mark or count. This type of shipment, for which the vessel is the container, such as LNG or oil tanker vessels, falls under the authority of the U.S. Coast Guard, now part of the Department of Homeland Security.