Modern traffic control devices to improve safety at rural intersections.

Details

• Creators:
  Fitzpatrick, Kay ; Chrysler, Susan ; Sunkari, Srinivasa ; Cooper, Joel ; Park, Byung-Jung ; Higgins, Laura
• Corporate Creators:
  Texas Transportation Institute
• Corporate Contributors:
  Texas. Dept. of Transportation. Research and Technology Implementation Office ; United States. Federal Highway Administration
• Subject/TRT Terms:
  • Traffic control devices
  • Rural highways
  • Intersections
  • Highway safety
• Publication/ Report Number:
  FHWA/TX-12/0-6462-1
• Resource Type:
  Tech Report
• Geographical Coverage:
  Texas
• Corporate Publisher:
  United States. Federal Highway Administration
• Abstract:
  "Engineers with the Texas Department of Transportation (TxDOT) frequently make changes to traffic control devices ; (TCDs) to improve intersection safety. To use available funds judiciously, engineers make incremental changes in ; order to select the least costly yet effective improvements. The goal of this project was to obtain a better ; understanding of modern TCD capabilities. Researchers conducted the following tasks: literature review, crash data ; examination, TxDOT district survey, laboratory survey, field study, and development of principles for selecting ; TCDs. Adding flashing lights to signs, either through beacons or embedded light-emitting diodes (LEDs), serves two ; purposes: to attract attention and to convey a message. The findings of this research demonstrate that while the lights ; do improve detection distance, legibility distance of the message suffers at night due to the glare of the lights. ; Cautious engineering judgment should be used when adding lights to any word message sign beyond a Stop sign ; because the legibility distance for the words will be shorter than when lights are not present. For Stop signs, the ; unique color and shape of these traffic control devices prompts drivers’ responses to them long before the word “stop” ; is actually read. The driving study found no difference in sign detection at night between those with an overhead ; flashing beacon and those where the ground-mounted sign has embedded LEDs. The detection distances observed for ; the signs with lights in this study were extremely long, over 2000 ft in most cases. The other general observation ; regarding the magnitude of the results is that for all of the Stop signs, both lit and unlit, the detection distance for sign ; recognition was always greater than stopping sight distance. So the existing static Stop signs are sufficiently visible ; for an alert driver under clear weather. The research project found that there appears to be a benefit to detection from ; dimming the LED brightness at night. The LED sign set on the high brightness setting was detected furthest during ; the day, while the lower setting was detected best at night. The research concluded with guidance principles to ; consider when selecting countermeasures for rural stop-controlled intersections."
  More +
• Format:
  PDF
• Funding:
  Project 0-6462
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/23644/dot_23644_DS1.pdf
• File Type:
  [PDF - 4.19 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:d4d844764459b2169161ac59211e5170bc12dbe83c45807105b44576654dadca8d11e8797831c59f9681301ecd84afdce7a4148e0690cc477d9791d6ea249688