We welcome disabled riders within TREC GB, but do not have separate classes, for those with disabilities.
Each rider and their condition can be taken into account following Rule 3-1-11 page 19 of the British TREC Rulebook. This section refers to tack that riders can carry whilst competing.
In each and every case, the rider will need to contact the Club or competition organiser in the first instance, stating your/their needs.
Within TREC, all obstacles on a PTV course can be omitted if necessary, as long as you stop and inform the judge at each obstacle. You will simply receive a zero for that obstacle. Many able bodied riders decline to do obstacles as well.
For colour blind competitors, they can simply ask the organiser for a different coloured drawn line, but again they must pre warn the organisers.