It has been shown that the use of CIE standard r-tables, instead of actual reflection properties of stabilised pavements, frequently leads to non-compliance with EN 13201 standard, particularly in terms of uniformities. Furthermore, the conventional observation geometry of 1° does not represent the preferred observation geometries of different road users in urban areas. In this paper, we present the device COLUROUTE2 that can be used to measure the r-table of a road surface on site for observation angles between 1° and 10°. Our experimental campaigns carried out on 18 different pavements (with bituminous mixtures and cement concretes) confirm that the CIE road photometric indicators S1, Q0 and Qd generally decrease as the observation angle increases. Our results show that the assumption of equivalence of Q0 and Qd measurements between 1° and 2.29° in the CIE 144 technical report is not always valid, but there are strong correlations between the different observation angles.
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