JAM START
Each team fields 4 Blockers and 1 Jammer. Blockers start anywhere between the Jammer Line and the Pivot Line, 30 feet (9.15 meters) away. Jammers start behind the Jammer Line. Play starts with a single whistle blast
BLOCKERS are simultaneously focused on stopping the opposing Jammer from passing them and assisting their Jammer to pass the opposing team’s Blockers. The pack is formed by the largest group of Blockers with players from each team on the track.
COMMON REFEREE SIGNALS
PIVOT is the Blocker that wears the stripe on their head. They are the only Blocker that is allowed to accept a star pass from the Jammer, thus becoming the new Jammer and gaining the ability to score points.
FIRST PASS
During the first pass, the first Jammer to pass all skaters in the pack legally is Lead Jammer. Lead Jammer status is signaled by the officials blowing two short whistle blasts and pointing at the Lead Jammer.
SECOND PASS
In subsequent passes, Jammers earn 1 point for each opposing player they pass legally. The opposing Blockers will try to stop the Jammer, while helping their own Jammer through the pack.
Two 15-skater teams play two 30-minute periods. Each period consists of multiple "jams." Each jam is an opportunity for both teams to score points, and ends after 2 minutes or when the Lead Jammer calls off the jam.
It is legal for a skater to block opponents with their hips, rear, and shoulders. It is not legal to block to the back, to trip, elbow, or to back talk officials. Players committing illegal actions are penalized 30 seconds and their team plays short for that time.
JAMMERS wear a star on their helmets and are the scoring players for each team. The Jammers attempt to pass the opponents as many times as possible by sprinting around the track and lapping the pack.