IAAF Competition Rules 2008

Rule 165

Rule 165.24e

The official time will be the time elapsed between the start gun and the athlete reaching the finish line (Gun Time). However, if an athlete crosses the start line after the start gun, his time elapsed between the start and finish line (Chip Time) can be made known to the athlete but will not be considered as official time.

(Race prizes will be awarded using official time only)