EVALUATION OF SIX ACTIVE WARNING DEVICES FOR USE AT RAILROAD-HIGHWAY GRADE CROSSINGS.

Six new active railroad-highway grade crossing warning devices were evaluated under controlled laboratory testing conditions. The six devices included two alternatives for each of three basic systems - four quadrant gates (with and without skirts), four-quadrant flashing light signals (with and without strobes), and highway traffic signals (with one and with three white bar strobes). The evaluation involved testing the performance of each of the six devices in a near realworld environment to identify the three most desirable devices for subsequent field testing. Four-quadrant gates with skirts tended to be a superior system in all categories of analysis.