The effectiveness of automatic warning devices in reducing accidents at grade crossings in California. Paper prepared for the 55th Annual Meeting of the Transportation Research Board TRB, Washington, D.C. January 1976.

The effect of California's automatic warning device program on the frequency of vehicle-train accidents in general is measured and specific crossing locations are examined to appraise the capabilities of automatic warning devices in reducing average vehicle-train accident and severity rates. Results indicate that the installation of automatic gates can be expected, on the average, to reduce vehicle-train accidents by 70% per crossing year and related deaths and injuries per year by 89% and 83% respectively.