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Schedule variability linked to fatigue and human factors incidents

Working-Schedule

Schedule variability linked to fatigue and human factors incidents in new US Department of Transportation, Federal Railroad Association study.

In April 2014, the US Department of Transportation’s Federal Railroad Association (FRA) released a new report which examines a link between work shift start time variability and an increased risk of human factors accidents.

Their research concluded that in fact, the greater the inconsistency in the time of day works shifts are scheduled to start, the greater the level of worker fatigue and associated accident risk.

To assist in reaching these conclusions, Fatigue Science’s Fatigue Avoidance Scheduling Tool (FAST) was used to measure the level of fatigue in various work schedule scenarios. The FRA researchers used a FAST score below 90 [1] to determine if fatigue was present, and then measured the amount of time workers spent below that criterion during their working hours.

Where schedules (during which an accident had occurred) exhibited a high rate of start time variability, FAST demonstrated the workers were spending as much as 50-60% of their time below the fatigue score criterion that was set for this study.

The report concludes:

Fatigue, as measured by the FAST score, was also shown to be a function of start time variability. While it was previously demonstrated that fatigue was a general function of sleep and work schedules (Raslear et al., 2011), this report extends that finding to specify start time variability as a critical aspect of work schedules when considering fatigue and the probability of an accident.

Key takeaways:

  • FAST technology is trusted by the US Department of Transportation, Federal Railroad Administration as a tool for accurately predicting fatigue and levels of fatigue in their work schedules
  • Fatigue is not only a factor for night shift or rotating shift workers
  • Day shift workers can be subject to increased levels of fatigue if their work shift start times are inconsistent.
  • Evidence-based decisions can be made that effectively reduce fatigue without adversely affecting operations.

1. The Fatigue Avoidance Scheduling Tool (FAST) uses scientifically-valid modelling algorithms to measure potential fatigue in work schedules – retrospectively for incident analysis, or in future schedules to optimize planning. FAST identifies that a score of 90 is associated with a 10% reduction in reaction time and 1.5x increased likelihood of a long lapse (or microsleep) – these associated performance changes increase as the FAST score for a schedule roster or worker lowers.

It’s 3 am, do you know how fatigued your workers are?

When the news of the Chicago train derailment came across our desks last week, we immediately took notice of the time of day the incident occurred. We know from experience and science, that 3 AM is not an optimal time for us to be up and about, performing safety sensitive tasks.

In our 24-hour society, however, the world doesn’t shut down at night so that everyone can go to sleep. Police officers need to respond to emergencies, nurses need to tend to patients, machinery operators need to make sure facilities keep running, and transportation workers need to make sure travellers are delivered safely to their destinations – at all hours of the day.

The responsibility to ensure these, and other shift-related jobs, are performed effectively and without risk to human safety must be shared by both the employer and the worker. There are number of variables which can contribute to someone’s level of fatigue on the job – Are the work shifts inconsistent? Does their work schedule give them enough time off to sleep? Does the worker have a sleep disorder? Does the worker have children at home who are keeping them up? Does the sleeping environment of the worker allow for restful sleep? Does the worker make an effort to obtain 7-9 hours of sleep per day? … this list could go on.

The fact is, all of these specific variables (and more) can be addressed if an employer asks two questions:

  • Does the work schedule provide the worker with the opportunity to maintain regular, sufficient sleep?
  • Is the worker taking advantage of the sleep opportunity being provided to them?

Obtaining objective answers to these questions is actually easier than one might think. The technology and tools to analyze work schedules and measure worker’s sleep is commercially available. (Full disclosure here, we are talking about Fatigue Science technology.) These tools can help employers identify the possibility of worker’s accumulating sleep debt based on their schedules, in a scientifically-validated and meaningful way. They can also help organizations identify if their workers are indeed accumulating risk-inducing levels of sleep debt due to insufficient sleep, whether related to schedule, lifestyle, health or a combination of these factors. By identifying the causes of fatigue in the workplace, organizations and employees can start to manage these variables.

In the case of the O’Hare Airport train crash, the operator has admitted to falling asleep while driving. Additionally, it was noted that she had previously fallen asleep on the job only last month. While it is extremely fortunate there have been no fatalities in either incidents, the risk to human life and the growing financial costs associated with last Monday’s event should serve as a wake up to organizations in any industry. It is not enough to just investigate whether or not fatigue is a factor in a workplace accident, employers and authorities need to take the next steps to address it and reduce the risk of it happening again. Whether a roster of train operators, police officers, or heavy machinery operators, Fatigue can be both measured and managed – before someone makes a mistake that puts themselves, and other human life at risk.

Sleep advice for shift workers

Last week we wrote about circadian rhythm, a 24 hour natural cycle of changes that the body goes through, and it’s effect on sleep and fatigue. We know that our circadian rhythm dictates that we should be sleeping at night and awake during the day – In an ideal world that would be the case, but the reality is many people work in 24/7 environments which require them to challenge their body’s natural sleep and wake inclinations.

We work with a variety of industries and organizations who operate these 24/7 environments, to make sure workers are being scheduled in a manner that minimizes on the job fatigue and provides sufficient opportunity to sleep – so they can work as efficiently and safely as possible, regardless of what shift they are on.

The companies we work with do their part to reduce on the job fatigue, but to this end, it is also important that individual employees take advantage of the sleep opportunities provided to them. While it is not always easy to go to sleep during the day when your body wants to be awake, there are steps you can take to help get the best sleep possible:

Communicate with family and roommates – Talk to them about your schedule and what your needs are. Post a calendar in the house with both your work and sleep schedule, so that everyone will understand when you will be away and more importantly, when you will need to sleep.

Be consistent with your sleep – If you are always working the same shift, be consistent with your sleep schedule. Go to bed and wake up at the same time, regardless of whether it’s your day off or not.

Plan for change – If you work rotating shifts, plan ahead to change your sleep schedule by gradually delaying or advancing your sleep and wake up times towards the new shift for a few days. If you’re starting on a series of night shifts, try to take an afternoon nap before the first night shift.

Stick to daytime eating schedules – Have your heaviest meal during the day time, but don’t drink or eat too much within three hours of going to sleep. If you are working nights and need a snack, stay away from heavy, fatty foods which your body will have trouble digesting. Choose lighter options including fruit, vegetables, whole grains, low fat dairy and lean proteins, but don’t eat after 3 AM.

Get ready for sleep – Spend some time winding down and sending your body signals that it is time to go to sleep. Do relaxing activities, like reading or stretching, limit your exposure to sunlight and take a shower or bath. Don’t watch TV or spend time on the computer or smartphone. Avoid both coffee and alcohol.

Create a sleep zone – Making sure you limit outside noise and stimulation is particularly important if you are trying to sleep during the day. Use black out curtains on windows to eliminate natural light and use earplugs or turn on a fan in the room to mask outside noise.

We can’t change our biological predisposition to want to sleep at night and be awake during the day, but we can certainly apply our scientific understanding of it to reduce the impact of shift work on the quantity and quality of sleep we get in our 24/7 lives.