THE LEGIBILITY OF ROAD SIGNS DURING NIGHT DRIVING--AN ANALYSIS AND SOME RESULTS CONCERNING THE EFFECTS OF FROST

VAEGMAERKENS LAESBARHET VID MOERKERKOERNING. EN PROBLEMANALYS OCH NAAGRA RESULTAT ROERANDE EFFEKTEN AV FROSTBELAEGGNING

The objective of the present study was to compare the legibility of road signs with different kinds of retro-reflective sheeting under dry and frosty conditions at two levels of vehicle head-lighting. The results do not permit any general conclusions about the superiority of a certain kind of sign, but the interactions rather indicate that the best legibility is obtained by different signs under different conditions. The variation in legibility between various conditions is interpreted as effects of deviations from an optimal luminance level. With the study as a starting point an overview is then given in which various factors influencing the night-time legibility of road signs are presented. Beginning with this overview a model for an alternative method for legibility studies is discussed. Finally some of the results are discussed from the traffic safety point-of-view, and the large differences between arithmetic means and 5:th percentiles are observed. /TRRL/

• Corporate Authors:

  Swedish National Road and Transport Research Institute (VTI)

  Linköping,   Sweden  SE-581 95
• Authors:
  • Dahlstedt, SGR
• Publication Date: 1977

Language

• Swedish

Media Info

• Features: Figures; References; Tables;
• Pagination: 32 p.

Subject/Index Terms

• TRT Terms: Calcium; Carbon dioxide; Chemical reactions; Concentration (Chemistry); Corrosion; Diffusion (Optics); Drivers; Electrolysis; Frost; Headlamps; Hydroxides; Legibility; Luminous intensity; Mathematical analysis; Mathematical models; Neutralization; Night visibility; Oxygen; Reinforced concrete; Silicates; Steel; Temperature; Traffic safety; Traffic signs; Vision
• Uncontrolled Terms: Models
• Old TRIS Terms: Driver vision; Substitution
• ITRD Terms: 2585: Frost; 1342: Headlamp; 540: Legibility; 9052: Night; 4523: Reflectorized material; 553: Traffic sign
• Subject Areas: Highways; Materials; Operations and Traffic Management; Safety and Human Factors; I34: Steels and Metals;

Filing Info

• Accession Number: 00173329
• Record Type: Publication
• Source Agency: Transport and Road Research Laboratory (TRRL)
• Report/Paper Numbers: VTI Report No. 120 Monograph
• Files: ITRD, TRIS
• Created Date: Jun 28 1978 12:00AM