The Rules of Flat Track Roller Derby

1.9 - Clocks

1.9.1 - Each game will have separate penalty clocks, jam clocks, and period clocks.

1.9.2.1 - The official period clock starts on the jam-starting whistle of the first jam.

1.9.2.2 - The official period clock does not stop between jams unless a timeout is called. The period clock stops during a timeout.

1.9.2.3 - Officials must stop the official period clock between jams when time exceeds 30 seconds.

1.9.2.4 - The official period clock must be one that is highly visible to referees, teams, and fans.

1.9.2.5 - In the event of a malfunction or discrepancy, the official period clock may be updated during a timeout in between jams, based on a backup clock.

1.9.3.1 - The official jam clock starts on the jam-starting whistle.

1.9.3.2 - The official jam clock stops at the end of each jam (on the fourth jam-ending whistle).

1.9.3.3 - The official jam clock must be one that is highly visible to referees, teams, and fans.

1.9.4.1 - All penalty clocks stop between jams (see Section 6.2.4 for procedure).

1.9.4.2 - Penalty clocks are not required to be visible to referees, teams, or fans. While in the Penalty Box, skaters may request knowledge of how much penalty time they have remaining.