What is the minimum speed required in the Boston Harbor tunnels?

The minimum speed required in the Boston Harbor tunnels is set at 20 mph to ensure safe and efficient traffic flow. This speed limit helps prevent both congestion and potential accidents, as maintaining a consistent speed in enclosed spaces like tunnels is crucial for safe driving conditions. The regulations are designed to accommodate the unique characteristics of tunnel environments, where visibility may be limited and the possibility of sudden stops is increased.

Moreover, different speeds may be suitable for regular roadways, but tunnels often have specific speed limits that take into account their confined spaces and the potential for higher risk. While other options propose lower or higher speeds, they do not align with the safety and operational standards established for the tunnels. By adhering to the 20 mph minimum speed, drivers contribute to a safer driving environment for themselves and others.