Let's look at from the prototype view
Great...Been there....Done that..
First there is no room to stand between car and the dock or building.I been there when I worked at a warehouse..The dock door was wide enough for me to open the boxcar door.
A warehouse...I take it you only worked at one sir ???
Simply put a forklift doesn't have wings and it must go from dock to freight car floor.
No kidding...yer joking...did I ask that LOL
That's kinda like opening a dock door...didn't know they had cellars
I too retired from the railroad as a foreman and know for a fact there are various clearances depending on the year and codes, as stated above before your reply, UP is 9 feet from center of track, that's close to three feet of clearance of which you can check with your scale rule.
A dock plate can be used at doors to reach the load but,there are safety and OSHA rules to follow while placing a dock plate.A dock plate is also known as a dock bridge..
Don't agree, I never put any employee in jeopardy of personal injury, concerning Safety, we used dock plates an were secured per our company's safety policies, A loaded forklift due to height of dock to car, and the gap can be an accident waiting to happen as not all forklifts have big tires, OR balanced loads, we too had an area very close dock, we still used dock plates. Also some load had a very Hi center of gravity, four foot height of forks moving over two tons.
As far as tank cars and covered hoppers there is plenty of room since you're using a hose and air powered vibrators or pumps to unload these cars.
And yes there is a hose that fits on the unloading gate of a covered hopper.