What should be the primary focus when determining green phase durations for signals?

The primary focus when determining green phase durations for traffic signals should be optimizing traffic and pedestrian safety. This emphasis is crucial because the primary function of traffic signals is to manage the flow of vehicles and pedestrians in a safe and efficient manner. Properly timed green phases allow for a smooth flow of traffic, reducing the likelihood of collisions and ensuring that pedestrians can cross streets safely without being caught in the intersection during an unsafe phase.

When green phases are timed optimally, they can accommodate actual traffic patterns, leading to fewer aggressive driving behaviors such as speeding or running red lights, which can result from frustration due to inadequate signal timing. Additionally, safety for pedestrians is enhanced when the signal phases are designed to provide adequate time for crossing, considering factors like pedestrian volume, crossing distances, and walking speeds.

While minimizing installation costs, meeting regulatory standards, and adjusting to geographical location are important considerations, they should support the overarching goal of ensuring safety. These factors can influence signal design and operation, but ultimately, traffic and pedestrian safety must take precedence in the decision-making process regarding green phase durations.