School zones in the United States require compliance of drivers to decreased speed limits during school start and end times, typically indicated by flashing beacons and warning signs. This study examined school zone safety by evaluating the effects of speed limit differentials on driver speeds in active school zones, the influence of roadway characteristics on driver behavior, and crash costs associated with school zones. The main goal was to attain a sustainable school zone safety policy. The analysis used speed observations from 378,506 vehicles, school and roadway characteristics, and crash data (2014 to 2018) across 18 study sites. Results showed that 85th-percentile speeds often exceeded posted speed limits during both active and passive school zone periods, with greater non-compliance being associated with larger speed limit differentials. Driver speeds were influenced by school zone status, vehicle type, time of day, traffic signals, street parking, and crosswalks. On average, speeds were 6.2 mph higher during passive periods than during active periods. However, high crash rates were observed during active school zone periods. Crashes during active periods resulted in average crash costs that were 52.5% lower than those during passive periods. The findings provide insights into human factors and mobility behavior in school zones, allowing transportation agencies to make informed and sustainable decisions for school zone design and safety.
Khattak et al. (Mon,) studied this question.