Fatal crash involvement by multiple-trailer trucks

Considerable uncertainty surrounds the relative safety of combination trucks with two or three trailers, compared to those pulling single trailers. This article uses data on conditions present in 5889 fatal crashes involving combination trucks to examine the extent to which these conditions vary for the two configurations. Using two complementary techniques, multiple classification analysis and automatic interaction detector, we evaluate the additive and interactive effects of these conditions. We conclude that multiple-trailer trucks are more likely to be involved in fatal crashes in the following conditions: darkness; snow, slush, or ice on the road surface; involvement of three or more vehicles, indicating at least moderate traffic volume; and higher-speed facilities with 65 to 75 mph limits.