(1) You must ensure that derail and/or bumper blocks are provided on spur railroad tracks where a rolling car could contact other cars being worked, enter a building, work or traffic area. This does not apply to cars being moved by a locomotive, switch engine, donkey engine, or a car puller, but only to cars which are "cut loose." The standard does not apply to "cut loose" cars in railroad yards where trains are made up using gravity feed arrangements.

(2) You must employ a clearly audible warning system when cars are being moved by car pullers or locomotives, and when the person responsible for the moving does not have assurance that the area is clear, and it is safe to move the car or cars.