CDL Hazardous Materials Practice Test

The correct answer is to never shift gears while crossing a railroad track. This guideline stems from safety protocols designed to ensure the vehicle remains stable and avoids stalling on the tracks. Shifting gears can cause a loss of power or control, increasing the risk of being caught on the tracks, which can lead to dangerous situations, especially when a train approaches.

When a vehicle is placarded, indicating it carries hazardous materials, maintaining control and ensuring the vehicle operates smoothly over the tracks is crucial. Stopping before crossing is also a critical consideration, but once you start crossing, shifting gears could introduce unnecessary risk. Acceleration or shifting gears can create instability, which is particularly hazardous when dealing with potentially dangerous cargo. Thus, maintaining the current gear and proceeding with caution helps prevent accidents and ensures a safer passage across railroad tracks.