RADIOLUMINESCENT LANE DELINEATORS FOR WET-NIGHT VISIBILITY

A theoretical and experimental program was undertaken to evaluate the feasibility of using radioluminescent light sources (with hydrogen-3 or krypton-85) as roadway lane markers. Simulated markers using ultraviolet light stimulation and a ribbed coverplate to counteract Fresnel losses were built and matched to the luminance of actual radioluminescent materials. The radioactivity required to fabricate a comparable single marker is estimated to be 240 curies of hydrogen-3. The luminance when viewed at 1.5 deg, is approximately 1.2 scotopic footlambert (4.1 scotopic cd/sq m). Subjective visibility tests of simulated radioluminescent markers using observers in an instrument test vehicle established the visibility of a dry marker as 350 ft (107 m) and of a wet marker as 275 ft (84 m). These values are greater than the visibility distance for a paint stripe or used retroreflector but are less than the values for a new retroreflector. Radioluminescent markers using hydrogen-3 are therefore sufficiently bright but costs ($1.00 per curie) are high and there is a potential for radiation overexposure in an accident situation at a stockpile or storage facility. /FHWA/

• Corporate Authors:

  IIT Research Institute

  10 West 35th Street
  Chicago, IL  United States  60616
• Authors:
  • Semmler, R A
  • Viergutz, O J
  • Wakely, H G
  • Wilner, K
  • Betz, H
• Publication Date: 1976-8

Media Info

• Pagination: 105 p.

Subject/Index Terms

• TRT Terms: Highway delineators; Hydrogen; Noble gases; Paint; Radiation hazards; Radioisotopes; Retroreflectors; Road markings
• Old TRIS Terms: Delineators (Traffic); Krypton; Traffic marking
• Subject Areas: Highways; Operations and Traffic Management;

Filing Info

• Accession Number: 00179504
• Record Type: Publication
• Source Agency: Federal Highway Administration
• Report/Paper Numbers: FHWA-RD-77-115 Final Rpt., FCP 31I1-123
• Files: TRIS, USDOT
• Created Date: Aug 27 1978 12:00AM