River Tow Boat : A shallow draft, low free board, self-propelled vessel designed to tow river barges by pushing ahead. For purposes of this section, the term does not include other towing vessels
US Department of Labor, Occupational Safety & Health Administration, Shipyard Employment eTools - Glossary, Washington, DC, USA 2012. http://www.osha.gov/SLTC/etools/shipyard/glossary. html, (Shipyard Employment - Amer) {562}