What is the purpose of safety zones at high-traffic railroad crossings?

The purpose of safety zones at high-traffic railroad crossings is to provide safe areas when trains are approaching. These zones are established to ensure that people, whether they are pedestrians or vehicle occupants, can stand clear of the tracks while waiting for a train to pass. Safety zones are strategically located to minimize the risk of accidents by indicating where it is safe to await the train's arrival without being in the path of oncoming trains. This is crucial for enhancing safety at crossings where there is a high volume of train traffic and where the potential for accidents is elevated.

The other options do not align with the primary function of safety zones. Marking areas for train repair, serving as waiting areas for passengers, or indicating the presence of train staff do not directly relate to the safety measures intended to protect individuals from oncoming trains.