4.14 Human Factors
4.14.1 Older Drivers & Pedestrians
Older drivers and pedestrians are a significant and growing segment of the road user population and should be accommodated in the design of road and pedestrian facilities to the extent practical. Research has shown that enhancements to the highway system to improve usability for older drivers and pedestrians can also improve the system for everyone.
The most practical enhancement to be considered when related to better accommodate older drivers is to increase the sight distance of the facility, which may be accomplished through increased use of decision sight distance. The gradual aging of the driver population suggests that increased use of decision sight distance may help to reduce future crash frequencies for older drivers.
The factors that could improve roadway and traffic control features for making driving easier for older drivers include:
- Design for the 95th or 99th percentile driver where appropriate;
- Improve sight distance by modifying designs and removing obstructions;
- Provide decision sight distance in advance of key decision points;
- Simplify intersections and interchanges that involve multiple information reception and processing;
- Consider alternate designs to reduce conflicts;
- Increase use of protected left turns;
- Increase vehicular clearance times at signalized intersections;
- Increase walk times for pedestrians;
- Provide wider and brighter pavement markings and paint median noses;
- Provide larger and brighter signs;
- Reduce sign clutter;
- Provide information such as advance warning signs for upcoming traffic movements;
- Provide rumble strips or profile pavement markings;
- Provide intersection channelization; and
- Reduce intersection skew.
The
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provide additional information for modifying geometric design elements and traffic control devices to better meet the needs and capabilities of older road users.