The benefits that can be realized by the top unloading system with respect to personnel protection are numerous. Note that these benefits are contingent to availability of a top access platform with drop gangway (or equivalent). The person assigned to unload the tank car is not placed in a compromised position when removing the plug from the valve outlet for hook-up to the transfer hose (or pipe). When utilizing a bottom unloading system, it is very common for a person to strike their head, back, or shoulders on the "belly," or undercarriage, of the tank car. The grab irons and ladder on the sides of the tank car present similar potentials for injuries. The track rails can also contribute to trips or sprains that may be incurred when departing from the bottom of the tank. These factors are especially compounded when/if a problem, such as a leak, is encountered while attempting to connect to the tank car. Potential for chemical exposure, in the form of material that may have leaked from the fittings under the tank car while standing, or crouching, under the tank car. These factors are not present when transferring from the top unloading valve. Access and egress are not impeded, and overhead obstructions are not present when working on the tank car platform.

The general consensus amongst caustic soda tank car users is that a cost prohibitive amount of air is necessary to unload a tank car from the top. The only air that would be needed to initiate transfer via pump would be sufficient pressure to lift the caustic solution approximately 12.5 feet, or roughly 8.1 psi (10 pounds air pressure would adequately 'prime' a pump). Once a pump prime has been established, the unloading will proceed I the same timeframe as would be customary for unloading from the bottom. The manway, or, at a minimum, the one-inch vent valve, should always be opened when unloading caustic soda by pump. If unloading has been performed by air from the bottom of the tank car in the past, there would be an insignificant increase in the amount of air used.

With respect to environmental protection, top unloading of tank cars offers the benefits of gravity working in the user's favor. A broken connection on the unloading hose (or pipe) from the top of the tank car will not result in the potential loss of the entire tank contents, as gravity will serve to hold the contents in the tank car, assuming pump transfer and proper venting of the tank. A similar type situation on the bottom unloading connection could very easily result in the entire tank car contents being lost to the environment before a valve could be properly secured. This type of situation also highlights the personnel protection benefits gained by top unloading vs. bottom unloading. Incidental leaks from the threaded connections made when connecting to the transfer system also have the potential to be minimized, if not eliminated, as improved positioning afforded by working on the top of the tank cars.