Maximum wheels diameter may also be restricted depending on the sanctioning body and race organizer. Riders participating in sanctioned racing events are required to wear safety equipment including: Hard-shell helmet with chin strap and face shield or goggles Leather or Kevlar racing suit Leather or Kevlar gloves Sturdy Shoes Race courses are usually held on mountain roads but have been held on city streets as well. Courses can range in length from 0.5 to 3 miles (1 to 5 km) and vary in layout (number and severity of turns). Racing can take the following formats: Single elimination with 2, 4, or 6 racers at a time Double elimination with 2, 4, or 6 racers at a time Timed trials No elimination points system (points for each finishing position in several heats) Mass runs, with up to 20 racers at a time (positions are decided by the order they cross the finish line) Governing bodies There are currently two worldwide governing bodies for street luge, the International Gravity Sports Association (IGSA) and the International Downhill Federation (IDF). The ruling body for street luge during the 1997–2001 X Games was the IGSA. Notes References Kahn, Jeremy (1981–). Street Luge 101. Kahn Productions. (DVD) 2003 Lott, Darren (1961–). Street Luge Survival Guide (1st ed.). Gravity Publishing. 1998 Nichols, John (1966–). Street Luge. Raintree Steck-Vaughn. 2002 External links Street-luge.com street luge online forum International Gravity Sports Association International Downhill Federation Street Luge PDX GravityDB.com Gravity Sports Database Gravity Sport University video of street luge by Yvon Labarthe (World series champion 2009) Street Luge video collection Frank Williams Boardsports Racing Sports originating in the United States