LONDON, England — It is normal at most track and field competitions for the crowd to be asked for silence at the start of races so athletes can concentrate on hearing the starters' signal.

At the Paralympics, however, the crowd is asked to be silent for the first three legs of the blind 4x100m relays to give the athletes and their guides the chance to make their baton changes with the aid of verbal commands.

Participants in the blind relays which are classified as T11/T13 have varying degrees of sight impairment and are allowed to use guides who would handle the batons. Some athletes who only have sight impairment are allowed to compete on their own, without guides.

In this the 14th Paralympics Games the London organisers have taken the decision to award medals to the guides, the first time this will be done since the competition started some 60-odd years ago.

In the long jump F11 where the athletes have severe sight impairment they take off from a much wider board and their guides are positioned just on the edge of the pit, issuing verbal commands and move out of the way at the very last moment.

The guides are also responsible for positioning the athletes at the start of their run up to the take off board.

On a number of occasions, the athletes veer off the path but fortunately on Tuesday there were no accidents.