The signal mentioned above are pretty much what a visitor to the SVRy will see. We have proscribed signals in our operating rules but their are a few others in common usage and some of our people have learned signals elsewhere creating some variations. What I have observed of the nonrule-book signals is that they make sense when seen in context. One signal not previously mentioned is the slow signal which for us is an arm held out perpendicular to the train and horizontal. Some will use both arms out then drop them to signal a "wash out" stop asuming the person giving the signals is on the ground. Obviously the more exagerated the signal motions are the easier they will be to see at a distance. We use the slow signal one car length from stopping at our depots. A conductor might use the slow if he were gaurding the leading car in a back up move as the train was approaching a switch. Similarly a brakeman would use it on the ground if the Loco is moving a little fast on a coupling move.