Define spot speed

Spot speed: Spot speed is defined as the speed measurement of an individual vehicle at a specific spot in a given interval of time.

Spot speed is always found out for the traffic volume of fewer than 500 vehicles per hour.

Spot speed study is useful in many ways; such as

• To use in planning traffic control and traffic regulations
• To use in accident studies
• To divide the speed trends
• To use in geometric design for re-designing existing highways or for deciding design speed for new facilities.
• To compare diverse types of drivers and vehicles under specific conditions.

The spot speed is affected by some environmental and physical features of the road like;

1. Pavement width
2. Curves
3. Sight distance
4. Gradient
5. Pavement unevenness intersections
6. Roadside developments
7. Traffic conditions
8. Motive of travel
9. Weather
10. Visibility
11. Enforcement
12. Type of vehicle and driver

Reasons for spot speed study:

1. Designing horizontal and vertical curves
2. Designing signal
3. Accidental analysis.