Neil Williams wrote:
On Apr 19, 11:50 pm, "Paul Scott"
wrote:

It has been suggested previously it is because LU do not normally allow
maintenance staff access to the live railway.

Though I imagine red is almost as visible. Several European railways
including SBB, OeBB and DB use it.

I think the problem with red in the UK would be that red/orange is the
colour of staff vis vests, and at a distance a fast approaching train
might be mistaken for a person in the distance wearing a vis vest.

Rgds

Denis McMahon