Main Page | See live article | Alphabetical index A double-hulled tanker is a large tanker ship used for transporting liquids (usually petroleum). The ship has two hulls to prevent the liquid cargo from spilling; if the outer hull is breached, the inner hull keeps the transported substance in place. Double-hulled tankers were required after the Exxon Valdez oil spill. The United States Congress passed The Oil Pollution Act of 1990 requiring double-hull tankers now, but allowing the transportation companies until 2015 to replace existing tankers. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.