Samenvatting
The legibility of 170 mm high with text on road signs was investigated during rural night driving. It was shown that reading distances were the greatest for text with effective reflective intensities in the approximate range of 2-10 mcd/lux cm 2. In order to maintain an acceptable readability of the road signs in use, it was recommended that retroreflective materials used on signs have a reflective intensity above 4 mcd/lux cm 2..