Retroreflective Traffic Control Devices
FHWA Recommends Ready-to-Use Safety Technologies
Retroreflective Traffic Control Devices - A technology that facilitates safe navigation of the roadway for all drivers
More Than Half of All Traffic Fatalities Occur At Night
While nearly a quarter of all travel occurs at night, about one-half of traffic fatalities occur during nighttime hours (including dawn and dusk hours). Out of the 42,116 fatalities that occurred in 2001, 20,648 were nighttime fatalities.
Highway statistics reveal a nighttime fatal crash rate that is more than three times the daytime rate. And there are more injuries and more property damage in nighttime crashes.
In 2001, problems with driver vision, vehicle, hardware, or environmental conditions are cited as “related factors” in some fatal crashes. Since more than half of all fatal crashes involve only a single vehicle, the final statistic may greatly underestimate the impact of vision and visibility on driving safety.
Night Travel and Fatalities
Why There Are So Many Nighttime Crashes
Drivers need visual cues to alert them to upcoming driving conditions. During daylight hours, drivers have many visual cues to help interpret roadway alignment such as signs, pavement markings, roadside barriers, and vegetation.
These visual cues are extremely important. They help drivers navigate the roadway by communicating the needed regulatory, warning and guidance messages to drive safely.
One reason there are so many nighttime crashes is because drivers are less able to see these visual cues – whether it be a sign, a pavement marking or some other type of traffic control device.
Nighttime Roadway Needs of An Aging Driving Population
Although older drivers are not the cause for the high nighttime fatality rate, providing nighttime visibility is becoming increasingly important as our driving population ages.
Simply put, older people have a harder time seeing. Currently, 26.2 million drivers are 65 years or older. By 2010 an estimated 33.7 million drivers will be 65 years or older. Increasing nighttime visibility is extremely important for this growing segment of drivers.
FHWA RECOMMENDS THE USE OF RETROREFLECTIVE TRAFFIC CONTROL DEVICES:
A Technology That Facilitates Safe Navigation Of The Roadway For All Drivers
Why Retroreflective Traffic Control Devices Prevent Nighttime Crashes
Headlights and roadway lighting help to illuminate the roadway but often they are not enough to meet the needs of nighttime drivers.
Retroreflective materials on signs, pavement markings and other traffic control devices help offset the lack of visual cues in the nighttime driving environment because they are more visible to a driver.
This is why retroreflective control devices should be used; the sooner a driver sees a sign or a pavement marking, the sooner a driver can take appropriate actions.
What is Retroreflectivity and How Does It Work?
Retroreflectivity is a technology that uses small glass beads or prismatic reflectors to reflect light back to its source.
When retroreflective materials are used on a roadway sign, it can make a sign seem to glow at night. By reflecting the light from a vehicle’s headlights back to the vehicle and to the driver’s eyes, the sign appears brighter and is more visible to the motorist.
Benefits of Retroreflectivity
- Promotes greater roadway safety
- Offsets the lack of visual cues at night
- Especially helpful to older drivers – a growing segment of the population
Managing Your Retroreflective Signs and Pavement Program
Retroreflective sign sheeting and pavement marking paints will degrade over time from weather impacts and traffic use. Also, a sign’s retroreflective effectiveness is lessened when the sign is bent, cracked or vandalized with paint.
So when is the best time to replace retroreflective signs and markings? Replacing them too soon will increase maintenance costs, but replacing them too late compromises safety and driving comfort. Replacing signs and pavement markings when they reach minimum levels of retroreflectivity is the best way to get the full life of signs and markings.
FHWA Retroreflectivity Levels
With input from state and local highway agencies, FHWA has developed minimum sign retroreflectivity levels and is proceeding with rule making to establish national levels.
These levels will support provisions in the Manual on Uniform Traffic Control Devices (MUTCD) to improve nighttime sign visibility on all roads, streets, and highways in the United States. They will enable highway officials to better manage their sign resources to maintain night visibility.
FHWA is also developing minimum retroreflectivity levels pavement markings.
For More Information, Contact:
Harry Taylor, FHWA Office of Safety
Phone: 202-366-2175
Email: harry.taylor@fhwa.dot.gov
