Skip to main content

Table 8 Roads without road lighting

From: Effects of weather conditions, light conditions, and road lighting on vehicle speed

Weather condition PSL Darkness–twilight Darkness–daylight Twilight–daylight
TF no. (km/h) (km/h) (%) (km/h) (%) (km/h) (%)
Clear
 9010 70 −0.1 −0.2 1.0 1.4 1.1 1.6
 9610 80 −0.2 −0.3 0.1 0.1 0.3 0.4
 9688 80 5.3 6.6 2.6 3.3 −2.7 −3.4
 9949 80 −0.4 −0.5 −3.0 −3.7 −2.6 −3.2
 9403 90 −1.0 −1.1 0.3 0.4 1.3 1.4
 9692 90 −1.8 −2.0 0.7 0.8 2.5 2.8
 7250 110 −1.2 −1.0 −0.5 −0.4 0.7 0.6
 9497 120 −1.7 −1.4 −0.9 −0.8 0.8 0.7
Mean   −0.1 0.0 0.0 0.1 0.2 0.1
Rain
 9010 70 −0.4 −0.6 0.0 −0.1 0.4 0.5
 9610 80 −0.2 −0.2 −0.5 −0.6 −0.3 −0.3
 9688 80 4.4 5.5 1.2 1.5 −3.2 −4.0
 9949 80 −2.3 −2.9 −6.1 −7.7 −3.8 −4.8
 9403 90 −1.1 −1.2 −0.2 −0.3 0.9 1.0
 9692 90 −2.0 −2.2 −0.2 −0.3 1.8 2.0
 7250 110 −3.4 −3.1 −2.7 −2.4 0.8 0.7
 9497 120 −1.0 −0.8 −1.7 −1.5 −0.8 −0.7
Mean   −0.8 −0.7 −1.3 −1.4 −0.5 −0.7
Snow
 9010 70 0.6 0.9 −1.8 −2.5 −2.4 −3.4
 9610 80 0.6 0.7 −2.7 −3.4 −3.3 −4.1
 9688 80 8.8 11.0 1.2 1.5 −7.6 −9.4
 9949 80 −1.5 −1.9 −1.6 −2.0 −0.1 −0.1
 9403 90 −2.9 −3.2 −5.8 −6.4 −2.9 −3.3
 9692 90 −10.0 −11.1 −5.3 −5.9 4.6 5.1
 7250 110 0.7 0.6 −6.4 −5.8 −7.1 −6.4
 9497 120 −9.2 −7.7 −6.6 −5.5 2.6 2.2
Mean   −1.6 −1.3 −3.6 −3.8 −2.0 −2.4
  1. Average speed differences (km/h) and percentage average speed difference in relation to posted speed limit (%) per road stretch (TF no.) between natural light conditions (darkness, daylight, twilight) and divided by weather conditions (clear, rain, snow)
  2. TF no. TF number (identification number for roads), see Tables 1 and 2, PSL posted speed limit. Mean values shown per weather condition group