Abstract
A digital Monte Carlo-type simulation was used to evaluate the effectiveness of an advance brake warning system (ABWS) in reducing rear-end collisions. The ABWS the authors evaluated activates the brake lights in response to rapid release of the gas pedal, which is characteristic of emergency braking. This reduces the lag in the onset of the brake light by the movement time from the gas pedal to the brake pedal. Using empirical distributions of driver perception reaction time and movement times, it was shown that the ABWS is most effective in preventing collisions on dry roads whenever the headway between vehicles decreases to 1.0 second or less. Vehicle speed was not a significant factor in crash prevention or severity reduction.