Stopping Sight Distance Calculator

Calculate Stopping Sight Distance



Formula

The formula to calculate the stopping sight distance is:

\[ \text{SSD} = 1.47 \times V \times 2.5 + \left(\frac{V^2}{30 \times (0.34782 + \frac{G}{100})}\right) \]

Where:

What is Stopping Sight Distance?

Stopping sight distance (SSD) is the total distance a vehicle travels from the point where a driver perceives a hazard to the point where the vehicle comes to a complete stop. It includes both the perception-reaction time and the braking distance. This calculation is crucial for road design and safety to ensure drivers have sufficient distance to stop safely under various conditions.

Example Calculation

Let's consider an example:

Using the formula to calculate the stopping sight distance:

\[ \text{SSD} = 1.47 \times 60 \times 2.5 + \left(\frac{60^2}{30 \times (0.34782 + \frac{5}{100})}\right) \approx 522.14 \text{ ft} \]

This means that the stopping sight distance for this scenario is approximately 522.14 ft.