Signing of on-permanent road surface conditions, such as ice, is difficult because hazard formation, location, and duration are unpredictable. Subsequently, many state transportation departments have begun to question the sensibility of depending material and personnel resources to maintain ice warning signs when little proof exists of their effectiveness in improving highway safety. This research statistically studies the effectiveness of ice warning signs in reducing accident frequency and accident severity in Washington State. The findings show that the presence of ice warning signs was not a significant factor in reducing ice-accident freqnecy or ice-accident severity. However, the authors were able to identify significant spatial, termporal, traffic, roadway and accident characteristics that influenced ice-accident frequency and severity. The identification of these characteristics will allow for better placement of ice warning signs and improvements in roadway and roadside design that can reduce the frequency and severity of ice-related accidents. (Author/publisher).
Abstract