This is a personal hatred of mine. Escalators dont comply with oh&s standards for stairs in this country (possibly internationally i dont know,  not my area of expertise) due to hieght and slope. As such public liability issurance does  not cover someone tripping on a stopped escalator. Our insurance people have actually gone so far as to say they would prefer a person to be hit by a service buggy than walk up a halted escalator. Its a whole different kind of legal stupidity.