How must a train proceed if there is a flagger present, but not one for each direction of traffic?

If a flagger is present but there isn't one for each direction of traffic, the train must proceed at a reduced speed to ensure safety. The appropriate speed limit in such situations is to not exceed 15 MPH. This allows the train crew to maintain a high level of alertness and respond quickly to any signals or commands given by the flagger, who is managing the flow of rail traffic in potentially congested or hazardous areas.

Operating at this reduced speed minimizes risks, gives the crew extra time to react in case of unexpected situations, and ensures compliance with safety protocols designed to protect both the train crew and any personnel on the track. It’s important to remember that safety standards require caution when flaggers are present, particularly when their coverage is not comprehensive for all directions of traffic.