In 2002, Caltrans measured the skid resistance of some 25-mm and 15.5-mm OGAC pavements in District I using both the ASTM E274 skid trailer and the BPT. The skid trailer ran at a speed of 64 km/h (40 mph). the reported value for a given section was determined by averaging the measurements made along the entire section. The reported BPN values were averages of three measurement obtained from randomly selected stations on each section. Testing was performed between September 23 and 25, 2002. At six different sites alone three routes and in three counties. The Data form this study did not produce a meaningful correlation between the two tests due to the considerable scatter and the limited range of data (Figure 26), However, the report suggested that if would be possible to develop a meaningful correlation between SN and BPN when more data were added and distinctions were made between the different types of mixes (19)