What is one requirement for bus drivers before stopping at a drawbridge?

Bus drivers are required to be aware of any signal lights or traffic control attendants before stopping at a drawbridge because these signals provide crucial information about the status of the bridge. They indicate whether the bridge is open or closed to traffic, which is essential for safe navigation. Traffic control attendants may also provide direction or control the flow of vehicles during the process of bridge operation. This awareness is vital in ensuring the safety of both the driver and the passengers, as well as minimizing potential traffic disruptions.

Observing the bridge for movement could be useful, but it is not a definitive requirement, as the signals and controls are the primary means of communication for the status of the drawbridge. Slowing down but not stopping does not prioritize safety and overlooks the need for thorough awareness of traffic control. Signaling to the passengers about a stop is courteous but not a legal requirement in the context of drawbridge interaction. Therefore, understanding and responding to signals and control measures is the most critical requirement for bus drivers in this situation.