In the mass start, all biathletes start at the same time and the first across the finish line wins. In this 15 kilometres (9.3 mi) competition, the distance is skied over five laps; there are four bouts of shooting (two prone and two standing, in that order) with the first shooting bout being at the lane corresponding to the competitor's bib number (bib #10 shoots at lane #10 regardless of position in race), with the rest of the shooting bouts being on a first-come, first-served basis (if a competitor arrives at the lane in fifth place, they shoot at lane 5). As in the sprint and pursuit, competitors must ski one 150 metres (490 ft) penalty loop for each miss. Here again, to avoid unwanted congestion, World Cup Mass starts are held with only the 30 top ranking athletes on the start line (half that of the pursuit) as here all contestants start simultaneously.
