Comparison of passenger vehicle and truck crash rates on toll roads.

The mileage based crash rates of tractor-trailer trucks compared to passenger vehicles have been widely debated. Valid comparisons have been difficult because the two vehicle types accumulate much of their mileage on different types of roads and traffic environments. To address this issue, crash rates were calculated for passenger vehicles and tractor-trailers operating on the same roads where mileage estimates for the two vehicle types could be obtained.