Preliminary indications are that the Metro-North train derailment was caused by the train operator falling asleep at the controls, and waking up too late to stop the speeding train from derailing. This is similar to other events in the transportation industry, including air traffic controllers sleeping on the job, truck drivers and boat captains falling asleep at the wheel, and pilots sleeping while at the stick.
Our first inclination is often to blame the transportation employees for falling asleep while they were supposed to be conducting important tasks. We express outrage at their indolence, question their professionalism, and consider them to be weak for not toughing it out through their drowsiness. After all, many of us have experienced sleepiness, and we didn't fall asleep on the job, right? How dare these transportation employees do so!
This strategy of blaming the transportation employee for falling asleep on the job is easy and perhaps comforting. This allows us to compartmentalize the issue as being due to a few bad employees not doing their job, and then we can be on our merry way. But it belies two sets of processes which are more complex than we tend to appreciate. One is the fact that employees are embedded in social systems that are often extremely disruptive to sleep. The other is that sleep is a set of physiological processes that cannot simply be dismissed without consequence.
Employees have a lot of activities that infringe upon their sleep. Some of these are outside of the work domain, including family demands and various sources of stress and anxiety in people's personal lives. However, many factors that infringe upon the sleep of employees originate at work. Most obvious are schedules that disrupt sleep. A large science on circadian processes indicates that people are physiologically well-suited for sleeping while the sun is down and being awake while the sun is up. A large number of physiological processes, including alertness and drowsiness, are determined by biochemical compounds that follow a 24-hour cycle, with troughs in alertness and spikes in sleepiness that occur at predictable times during that period.
Yet transportation employees are often asked to work during those spikes in sleepiness, and try to sleep during other portions of the circadian process in which they are far better suited for waking activity. As a result, we disrupt their sleep, leaving them vulnerable to sleeping on the job. Indeed, the Metro-North train derailment on December 1 was on a train line that started at 5:54am, a time at which people are still in the sleepy portion of their circadian rhythm. Those who work night shifts often develop what is referred to as shift work sleep disorder, in that their circadian rhythms never fully adapt to their night shifts. This entails difficulty sleeping during the day, and difficulty staying alert while working at night. Moreover, we often schedule employees to work rotating shifts, where they work at different times of the day on different days, never really giving their circadian processes a chance to settle down and stay stable.
We often ask employees to work extended shifts that cut into their sleep, and still expect them to be alert and effective the next day at work. My own research indicates that there is a clear relationship between work hours and sleep hours. Several industries, including some relevant to transportation, have regulations that limit the degree to which this can happen. But these regulations often still leave room for work schedules to infringe upon sleep.
A large scale study by the National Sleep Foundation found that 29 percent of Americans report extreme sleepiness or falling asleep at work in the past month. Sometimes this is indeed because people make bad choices in allocating time away from sleep. But oftentimes it is because of heavy demands placed on the employee by the organization they work for, and few industries have work schedules that infringe upon employee sleep as much as transportation. Yet when someone falls asleep on the job, we tend to assume it is because the employee is lazy and unreliable.
I recommend that we avoid taking the simple option of automatically blaming the employee. We need to look at the larger systems in which these employees are embedded, and how this influences the physiological processes that govern sleep. When employees fall asleep on the job, this should be an indicator that perhaps the work system is scheduled in a manner that is incompatible with circadian processes and sleep needs of employees. With this approach, it is possible to prevent future occurrences of employees falling asleep on the job rather than repeatedly taking the easy route of blaming the employees. We already know that a lack of sleep is dangerous. We should manage sleep systematically.