What is a potential danger of working under a moving train?

Working under a moving train presents significant risks primarily due to the potential for unexpected movements or derailments. Trains are massive and heavy, and they are capable of causing severe injuries or fatalities if someone is caught underneath as they pass. The inherent unpredictability of a train's movement—whether from acceleration, deceleration, or shifting on tracks due to external factors—poses a serious danger. This scenario is compounded by the possibility of a derailment, which can lead to catastrophic outcomes for anyone in the vicinity.

Other risks such as electric shock, exposure to harmful chemicals, and getting caught in automated machinery can occur in the broader context of rail work. However, when specifically focusing on the immediate and extreme danger of being under a moving train, the risk of injury or fatality from its motions stands out as the most critical concern. Understanding this risk underlines the importance of safety protocols and awareness around moving trains in any rail maintenance or service operations.