What is the red clearance interval defined as?

The red clearance interval is defined as the time required to completely clear the intersection after the signal turns red. This interval is crucial for ensuring traffic safety, as it allows vehicles currently in the intersection to exit safely before cross traffic is allowed to proceed. This period helps prevent potential collisions by ensuring that all vehicles have vacated the intersection, thereby reducing the risk of accidents as other vehicles begin to move once the signal changes.

The other options describe different aspects of traffic signal timing but do not accurately define the red clearance interval. For instance, the duration of the red signal before it changes again pertains to the overall timing of the traffic light cycle, while the time needed for vehicles to stop safely at a red light focuses on the braking distance, which is not the purpose of the clearance interval. Finally, the minimum wait time before a driver can proceed does not relate to the red clearance interval's function of ensuring the intersection is clear of traffic.