What is the section number for stopping sight distance in the AASHTO Green Book?

• A. Sec. 3.2.2.3
• B. Sec. 5.1.4.3
• C. Sec. 9.6.4
• D. Sec. 3.2.4

Answer: (A)

Stopping sight distance is a critical design element in roadway engineering, as it ensures that drivers have enough distance to perceive an obstacle or hazard in the road, react appropriately, and come to a complete stop safely. In the AASHTO Green Book, which provides guidelines for geometric design, the relevant section that details stopping sight distance is indeed found in Section 3.2.2.3.

This section specifically addresses the factors involved in determining the necessary stopping sight distance, including vehicle speed, grade, and perception-reaction time, which are essential for creating safe roads. Understanding this section is fundamental for transportation engineers when designing highways and intersections, as it directly impacts safety and operational efficiency.

The other section numbers listed do not pertain to stopping sight distance, thus broadening the context of design but not specifically addressing the critical measure of ensuring that vehicles can stop safely within a given distance.