What is the assumed height of a driver's eye above the pavement?

• A. 2.0 ft
• B. 3.0 ft
• C. 3.5 ft
• D. 4.0 ft

Answer: (C)

The assumed height of a driver's eye above the pavement is typically standardized at 3.5 feet. This height is based on various studies and research that seek to represent the average position of a driver's line of sight when operating a vehicle. It is used in the design of roadways, signage, and traffic control devices to ensure that visibility and sightlines are adequate for safe driving conditions.

The 3.5 feet measurement takes into account the average proportions of drivers as well as the typical position from which they observe the roadway and surrounding environment. When establishing criteria for safe sight distances, stopping sight distances, and other roadway design elements, this standard height is critical for ensuring that all road users can safely navigate and respond to conditions on the road.

In contrast, the other options indicate heights that are either too low or too high for typical drivers, which could lead to inadequate design considerations for visibility. Using heights significantly different from 3.5 feet could compromise the safety and effectiveness of traffic safety measures, making it essential to adopt the well-established standard of 3.5 feet.