Derailments rank as the most common type of accident involving major freight railroads, federal data shows. Equipment failures are increasingly responsible for derailments, and problems with equipment and train tracks accounted for nearly 60% of derailments nationwide last year.

Train derailments are often the result of a complex interplay between aging infrastructure and human error. According to safety data from 2024 and 2025, the leading cause remains track defects, such as broken rails, widened gauges, or "sun kinks" where extreme heat causes steel tracks to buckle. In the U.S., the shift toward "Precision Scheduled Railroading" (PSR) has led to significantly longer and heavier trains, which place immense mechanical stress on older tracks and bridges. Human error, including fatigue-induced mistakes by conductors or improper switching in rail yards, accounts for nearly one-third of incidents. Mechanical failures, such as "hot boxes" (overheated wheel bearings), also play a role, as seen in high-profile cases like East Palestine. While the total number of derailments has actually declined over the last decade, the severity and visibility of accidents involving hazardous materials have increased public concern.