Tuesday, July 17, 2012

Reading on the job: fatigue, boredom and distraction while underloaded

I have received a few queries asking for a view (or "the science") on reading during operational duty, particularly as a possible countermeasure against fatigue during nightshifts. This is in an air traffic control context, meaning reading while a controller on duty at workstation, but it would apply to many other safety-related contexts where people need to monitor.

This is a sticky issue. But it is the kind of issue where a human factors specialist is expected to give advice or at least some succinct guidance or points for consideration. This kind of query is rarely straightforward. The 'science', inasmuch as it is relevant, cannot be simply generalised from laboratories or other contexts, and there is rarely any possibility for controlled experiments to study the problem directly. So, is reading a suitable countermeasure against fatigue? Below are some of my thoughts on this issue.

The task of the air traffic controller, as with many other safety-critical roles, is increasingly visual with high demand for monitoring. Automated tools such as data link and conflict alerts are becoming more common. They usually do not have any associated audible alert or alarm and may not be expected or anticipated. As people naturally become more reliant on such automated aids for normal performance, the need for alertness is even greater.

But there can be fairly long periods of low activity. Reading during operational duty is fairly common during these periods. The motivation to read is one that we can all identify with. We have little tolerance for monitoring when understimulated, and naturally want to fill in the gaps with other activities. Stimulation is often at its lowest during a nightshift (particularly ~0200-0500), when we also experience heightened fatigue. In this scenario, reading may seem like a good idea to maintain alertness. 

But what are we really trying to combat via reading during periods of low activity? Most likely, we use reading to combat boredom rather than fatigue. Boredom is an unpleasant or even distressing state that we naturally wish to avoid. Reading can be stimulating (and effective to counteract boredom) but it can also be visually fatiguing (especially during night shifts). 


Reading, fatigue, boredom and distraction (Photo credit: Ani-Bee http://flic.kr/p/LaxT3 CC BY-NC-ND 2.0)

There is then the issue of distraction. Reading may mean reading from paper (book, newspaper, etc), an e-reader, a smart-phone or a tablet. Reading itself is a primary distraction from operational information, but smartphones and tablets introduce secondary distractions from other applications, such as emails, instant messages, tweets, status updates, notifications, etc - many of which are designed (or can be set) to capture attention (e.g. via pop-up notifications or alerts). 

Reading feels like the most natural way to repel boredom and so maintain stimulation, but at the same time it can increase fatigue and distraction and decrease vigilance and alertness - a situational irony. 

Then there are the legal implications. In the case of a serious incident or accident, reading non-operational material when visual detection may be safety critical could be raised in court, because reading takes attention away from the primary task (e.g. radar monitoring). An argument could be made (ignoring the whole context of the work) that if the person were not reading, then a problem (e.g. conflict) would more likely have been detected. 

It is important to separate the problems of fatigue and boredom because the countermeasures are different. Fatigue requires rest and sleep. Boredom requires stimulation. But often they come as a package, in which case fatigue will usually trump boredom, as fatigue is so much more difficult to counteract without prior planning. A better way to manage fatigue during nights might involve more frequent breaks and scheduled napping, as well as a well-designed shift system (see a EUROCONTROL literature review and Hindsight  Issue 13 on fatigue).

Combating boredom on an operational level also requires frequent breaks - there is positive evidence that light exercise such as a brisk 10 minute walk helps increase arousal. Breaks are only a partial solution, though, because the problem is one of job and task design.While these are not easy to change, while working on position, other tactics might include more active visual scanning (as opposed to reactive scanning), and increasing workload (e.g. combining sectors, offering higher service levels), or rotating activities, tasks or roles (e.g. sectors, positions or non-operational work). A 1996 EUROCONTROL-sponsored research project examined monotony in ATC, and came up with a few recommendations (page 184), but these do not shed much more light on the matter. Note that some other 'common-sense' tactics, such as playing music, can also be counterproductive because of distraction. In the longer term, more strategies are available via personnel selection (some people have a greater tolerance for boredom) and task, job and technology design (for instance, auditory alerts to complement visual information during specified hours), but these options are of little relevance to current operations. 

So reading itself is probably not an effective countermeasure for fatigue while on duty, but we have to recognise that the desire to read indicates another problem that needs to be addressed: boredom. Until we are able to design the boredom out of jobs, it would be useful, then, to share the practical strategies used by different people in different organisations and industries to maintain alertness and vigilance, and fend off boredom, in real world safety-critical environments.

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