What are "Slow-By" restrictions?

"Slow-By" restrictions refer to specific limits imposed on train speeds when trains are operating in close proximity to work zones or areas of potential hazard. The correct answer highlights that these limits require trains to operate at a maximum speed of 60 mph on adjacent tracks. This is particularly important for maintaining safety around maintenance activities or when other trains are operating under conditions that could potentially create risk.

By requiring trains not to exceed this speed, "Slow-By" restrictions help to protect workers on the tracks and minimize the chances of incidents occurring due to high-speed train movement. The focus on adjacent tracks specifically encompasses scenarios where trains might be passing near equipment or personnel, thereby reinforcing a controlled and safer operational environment.

In contrast, the other options do not encapsulate the specific nature of "Slow-By" restrictions as they either imply broader or irrelevant restrictions that do not directly relate to the speed regulations applicable in these scenarios.