This study determines the safety, economic, operational, and environmental consequences of requiring hazardous materials transporters, school buses, and passenger buses to stop at railroad crossings with active warning devices when the devices are not activated. The study included an assessment of the positive and negative impacts on accidents involving trains and those in which trains are not involved, traffic operations, fuel consumption, delay, pullout-lane construction and maintenance costs, and environmental degradation. Results indicate that not mandating stops at railroad crossing with active devices when the devices are not activated would reduce both train and nontrain accidents annually for all three classes of vehicles; the net annual decrease in train-involved accidents would be 2. 6, 10. 8, and 17. 4 percent for hazardous materials transporters, school buses, and passenger buses, respectively. The annual economic savings resulting from not requiring stops were estimated as 328,000 in accident costs; 1,241, 000 in pullout-lane construction and maintenance costs; 12,267,000 in excess fuel consumption; and 1,510,000 in delay.