The National Transportation Safety Board (NTSB) named crew member fatigue as the probable cause of a 2014 Union Pacific (UP) Hoxie, Ark., accident that killed two crew members and seriously injured two others.
Two Union Pacific trains collided in the early hours on Aug. 14, 2014, while traversing a turnout control point. NTSB's report on the accident found that the northbound crew had no indication of the impending collision and that the southbound train conductor was likely asleep at the time of the collision. The report also cited a lack of federal regulations governing sleep disorder and fatigue modeling tools as a contributing factor to the accident.
The Federal Railroad Administration (FRA) originally issued a safety advisory in 2004 on the dangers of sleep apnea and included a warning on the health issue again in another safety advisory issued on Dec. 3.
NTSB's official probabe cause declaration reads, "the probable cause of the accident was the failure of the southbound train crewmembers to respond to the signal indications requiring them to slow and stop their train prior to control point Y-229 because they were fatigued and had fallen asleep due to (1) the locomotive engineer's inadequately treated obstructive sleep apnea, (2) the conductor's irregular work schedule and (3) the train crew operating in the early morning hours when they were predisposed to sleep. Contributing to the accident was (1) the lack of a functioning positive train control system; (2) the use of an automatic horn sequencer that, when activated, negated the operation of an electronic alertness device; (3) the Federal Railroad Administration's failure to promulgate rules regarding sleep disorders; and (4) the absence of federal regulations requiring freight railroads to use fatigue modeling tools for train crew work schedules."
NTSB's report makes several recommendations to the FRA, Class 1, intercity and commuter railroads. NTSB wants FRA to require freight carriers to use fatigue models when developing work schedules, as well as develop and enforce medical standards. NTSB recommended that all commuter, intercity and Class 1 railroads, with the exception of Union Pacific, review their medical rules to ensure the railroad is informed of an employee's sleep disorder diagnosis and that periodic evaluations are performed to ensure the condition is being treated and the employee is fit for duty. To UP, NTSB recommended revising the railroad's medical rules to include sleep disorders on the list of reportable medical conditions. To all Class 1 railroads, NTSB recommended a revision to scheduling practices for train crews that includes science-based tools.