Intersection safety opportunities for the United States from international applications: A scoping review and practitioner roadmap.

INTRODUCTION Intersections account for approximately one-quarter of U.S. traffic fatalities and one-half of all traffic injuries annually, with pedestrians bearing a disproportionate burden. In 2023, 7,314 pedestrians were killed and an estimated 68,244 were injured in U.S. traffic crashes. Despite a modest year-over-year decline in preliminary 2024 data (projected 7,148 pedestrian deaths; 39,345 total fatalities), the U.S. injury burden remains substantially elevated relative to peer nations. Concurrently, the Federal Highway Administration (FHWA) adopted the 11th Edition of the Manual on Uniform Traffic Control Devices (MUTCD), effective January 18, 2024, reshaping the regulatory environment for intersection safety countermeasure adoption.

Method

This study examines whether three internationally deployed intersection safety treatments - in-pavement LED crosswalk lighting, vehicular countdown signal displays, and left-turn waiting areas - offer viable and evidence-supported pathways for reducing the U.S. pedestrian and vehicle conflict burden.

Results

In-pavement LED crosswalk lighting reduced mean vehicle approach speeds from 25.0 to 21.6 mph and vehicles passing during pedestrian presence from 1.72 to 1.06 per event in a controlled U.S. evaluation, though benefits decayed over a 9-month follow-up. Vehicular green- countdown displays (GSCD) expanded driver dilemma zones from 30 m to 58 m, increasing decision variability and crash risk; Taiwan's subsequent policy response restricted GSCD use nationally. Motor-vehicle left-turn waiting areas showed capacity gains (∼17.8% under modeled conditions) but elevated conflict severity with red-light running and out-of-area positioning. Two-stage bicycle turn boxes demonstrated no adverse safety signal in available U.S. collision data and are now standardized under the 11th Edition MUTCD.

Conclusions

AND PRACTICAL APPLICATIONS Three established comparator treatments - leading pedestrian intervals (LPI; ∼13% pedestrian crash reduction), modern roundabouts (∼76-90% severe crash reduction), and flashing yellow arrow displays - offer near-term high-confidence opportunities.