Human Factors and Macro Analysis Group, Transportation Safety Board of Canada, 200 Promenade du Portage, 4th Floor, Gatineau, QC, K1A 1K8, Canada.
Accid Anal Prev. 2019 May;126:64-69. doi: 10.1016/j.aap.2018.01.027. Epub 2018 Feb 2.
Canada's freight rail system moves 70% of the country's surface goods and almost half of all exports (RAC, 2016). These include dangerous goods. Anonymous survey of freight rail operating employees conducted by the Teamsters Canada Rail Conference (TCRC, 2014) revealed that many do not report getting enough sleep because of their work schedules, and that fatigue may be affecting their performance at work. Besides general impairments in attention and cognitive functioning, fatigue in railway operating employees slows reaction time to safety alarms and impairs conformance to train operating requirements. Shift scheduling practices can contribute to sleep-related fatigue by restricting sleep opportunities, requiring extended periods of wakefulness and by disrupting daily (circadian) rhythms. The primary goal of accident investigation is to identify causal and contributing factors so that similar occurrences can be prevented. A database search of Transportation Safety Board (TSB) rail investigation reports published in the 21-year period from 1995 to 2015 identified 18 that cited sleep-related fatigue of freight rail operating employees as a causal, contributing, or risk finding. This number represents about 20% of TSB rail investigations from the same period in which a human factors aspect of freight train activities was a primary cause. Exploration of accident themes suggests that management of fatigue and shift scheduling in the freight rail industry is a complex issue that is often not conducive to employee circadian rhythms and sleep requirements. It also suggests that current shift scheduling and fatigue management practices may be insufficient to mitigate the associated safety risk. Railway fatigue management systems that are based on the principles of modern sleep science are needed to improve scheduling practices and mitigate the ongoing safety risk.
加拿大的货运铁路系统承担了全国 70%的地面货物运输量和近一半的出口货物运输量(RAC,2016)。其中包括危险货物。加拿大卡车司机工会铁路会议(TCRC,2014)对货运铁路运营员工进行的匿名调查显示,由于工作安排,许多员工报告称睡眠不足,而且疲劳可能会影响他们的工作表现。除了注意力和认知功能的普遍障碍外,铁路运营员工的疲劳还会降低对安全警报的反应速度,并影响对列车运行要求的遵守。轮班安排实践会通过限制睡眠机会、要求长时间保持清醒和打乱日常(昼夜节律)节奏,导致与睡眠相关的疲劳。事故调查的主要目标是确定因果和促成因素,以便防止类似事件的发生。对 1995 年至 2015 年 21 年间运输安全委员会(TSB)公布的铁路调查报告进行数据库搜索,确定了 18 份报告将货运铁路运营员工的与睡眠相关的疲劳列为因果、促成或风险发现因素。这一数字约占同期 TSB 铁路调查中货运列车活动人为因素为主要原因的 20%。对事故主题的探讨表明,货运铁路行业的疲劳管理和轮班安排是一个复杂的问题,往往不利于员工的昼夜节律和睡眠需求。这也表明,目前的轮班安排和疲劳管理实践可能不足以减轻相关的安全风险。需要基于现代睡眠科学原理的铁路疲劳管理系统来改进调度实践,减轻持续存在的安全风险。