Pushing any car on a main haulage road is prohibited except (i) where it is necessary to push a car from a sidetrack that is located near the working section to the producing entry or room; (ii) where it is necessary to clear a switch or sidetrack; and (iii) on the approach to a cage, slope, or surface incline. However, where a rail transportation system is utilized and it becomes necessary to routinely push cars, the operator shall develop procedures for coordination and control of rail traffic, such as the provision of effective trip lights or other warning devices, and other safety precautions specific to the mine. Such procedures shall be subject to approval of the Chief.