What is the correct sequence of sight distances starting from the least critical?

What is the correct sequence of sight distances starting from the least critical?

• A. ISD, SSD, PSD, DSD
• B. SSD, PSD, DSD, ISD
• C. PSD, ISD, SSD, DSD
• D. DSD, SSD, PSD, ISD

Answer: (A)

The correct sequence of sight distances, starting from the least critical, follows the rationale of how each distance pertains to safe stopping and visibility for drivers. ISD, or intersection sight distance, is the least critical because it relates to the visibility required for a driver to see and react to oncoming traffic at intersections, allowing them to safely turn or cross. However, it is typically less critical than the other sight distances in terms of stopping capabilities. SSD, or stopping sight distance, is next in terms of criticality as it pertains to the distance required for a driver to perceive an obstacle, react, and come to a complete stop. This is very important for safety on the road. PSD, or passing sight distance, is higher on the criticality scale since it allows sufficient distance for a driver to complete a passing maneuver safely while considering the speed of oncoming vehicles. DSD, or decisions sight distance, is the most critical as it encompasses the distance a driver needs to have adequate time to perceive, react, and make driving decisions. This includes scenarios such as merging onto highways or encountering unexpected conditions. Consequently, the order starting from the least critical to the most critical is indeed ISD, SSD, PSD, and then DSD. This

The correct sequence of sight distances, starting from the least critical, follows the rationale of how each distance pertains to safe stopping and visibility for drivers.

ISD, or intersection sight distance, is the least critical because it relates to the visibility required for a driver to see and react to oncoming traffic at intersections, allowing them to safely turn or cross. However, it is typically less critical than the other sight distances in terms of stopping capabilities.

SSD, or stopping sight distance, is next in terms of criticality as it pertains to the distance required for a driver to perceive an obstacle, react, and come to a complete stop. This is very important for safety on the road.

PSD, or passing sight distance, is higher on the criticality scale since it allows sufficient distance for a driver to complete a passing maneuver safely while considering the speed of oncoming vehicles.

DSD, or decisions sight distance, is the most critical as it encompasses the distance a driver needs to have adequate time to perceive, react, and make driving decisions. This includes scenarios such as merging onto highways or encountering unexpected conditions.

Consequently, the order starting from the least critical to the most critical is indeed ISD, SSD, PSD, and then DSD. This