Final answer:
Railway crossings are especially hazardous for large, heavy commercial vehicles due to the increased stopping distances required. Traffic signals contribute to pedestrian safety by controlling vehicle flow. Safety planning includes accounting for these factors to minimize accidents.
Step-by-step explanation:
Railway crossings are potentially more dangerous for larger, heavier commercial vehicles primarily because heavier vehicles require longer stopping distances. The mass of a commercial vehicle adds to its momentum, meaning it takes more force over a longer period of time to bring the vehicle to a stop. This is critical at railway crossings where the timing and speed of an approaching train might be misjudged, leading to a higher risk of collision if the vehicle cannot stop in time.
Pedestrian safety at railway crossings and traffic intersections is an important concern. Traffic signals help manage vehicle flow and allow pedestrians to cross at appropriate times, thereby reducing the risk of accidents or the need for pedestrians to dodge traffic.
When it comes to judging the safety of crossing a road, distance perception is key. It is not just about the number of car lengths but also the speed of the oncoming vehicle and the pedestrian's walking speed. There is no universal safe distance since it varies with different traffic conditions and speeds.
Understanding the dangers associated with large vehicle stopping times, pedestrian crossing timings, and the effects of air pressure near fast-moving trains contributes to the overall traffic engineering and safety planning of public infrastructure.