As a discipline for study, fatigue still seems to be in its early days and this presents a challenge for safety professionals and researchers. Everyone knows what fatigue is because at some time we all suffer it, but try to define it and it is different things to different people.
Transport Safety Victoria (TSV), a division of the Department of Transport, brought together three speakers on the issue of fatigue management in early August 2011. The public seminar provided a good indication of the complexity of the occupational issue of fatigue management.
The first revelation in the seminar came from Dr Paula Mitchell who stressed that fatigue cannot be self-assessed. Researchers are struggling to create a widely accepted indicator for fatigue. There is no blood alcohol reading device for fatigue and the Independent Transport Safety Regulator in July 2010 expressed caution on the application of the bio-mathematical fatigue model.
The challenge is exacerbated by different perceptions of fatigue. Wiktionary offers these synonyms, some I had to look up:
- fatigue
- tiredness
- exhaustion
- weariness
- drowsiness
- lassitude
- sweat
- dyspnea
- yawning
- faintness
- fainting
- syncope.
The word that is missing from this list and the one that safety professionals and managers should examine closely and keep in mind is “impairment”. Impairment is most familiar in the OHS discipline from workers compensation definitions but the term needs to be reclaimed. SafetyAtWorkBlog’s definition of impairment is the difficulty in making decisions due to psychosocial factors. (Other suggestions are very welcome)
Fatigue is a contributory factor to impairment, just as is depression, stress, alcohol and drugs, workload and a range of other personal and social factors. All of these pressures need to be addressed in the work environment in order to produce a worker who is fit for work and is in a mental state where the likelihood of being injured, through poor decision-making, is minimised.
The TSV seminar understandably focussed on the risks for rail and tram drivers as this is the area where catastrophic risks exist but some of the information provided applied equally to other areas of the industry, such as maintenance crew. The report, based on work at Network Rail in the UK, by Fiona Kenvyn was perhaps the most widely applicable. The UK rail industry has managed fatigue for many years principally through shift limitations imposed after the inquiry into the Clapham Junction Accident in December 1988 conducted by Anthony Hidden QC. (These limits are referred to colloquially as the “Hidden limits” – during the seminar some of us could not understand why the limits were hidden if the industry, as a whole, used them)
Controlling fatigue through prescriptive working hours may work for a particular industry or company but the restriction of working hours in a broad social context, as France tried, has a poor track record for contemporary societies. But then fatigue management was not the primary motivation in the minds of the French politicians at the time.
In a conference paper* (not available online) provided at the seminar, Kenvyn, and colleagues, say that a more rounded approach to fatigue management is required that includes greater focus on roster design and a greater application of risk assessment.
Roster design, or control of working hours, is the ultimate aim, but risk assessment is more problematic. The fluffiness that often accompanies risk assessment may be part of the reason for the longevity of the “Hidden limits” in the rail industry, even though legislation has moved on from such prescription. Prescriptive safety controls are attractive because they make compliance clear. Gaining compliance may not be easy but there is a point where compliance can be reached. Fatigue however, and any of the psychosocial hazards in fact, is different for everyone. There are different tolerances, there are different symptoms and, from the information at the seminar, it is difficult to know when we are too tired to work safely. So how can such an amorphous hazard be controlled?
Perhaps it just cannot be controlled, as the individual variances mentioned in the previous paragraph can apply to any psychosocial hazard at work. Perhaps researchers are focussing too narrowly and “impairment” should be the universe within which the various psychosocial researches exist.
* “Fatigue management in the UK rail industry: Practical challenges in enhancing a fatigue management strategy” by Fiona Kenvyn, Nuno Cebola & Theresa Clarke
Hi all
As someone who has worked in the fatigue field since 1986 I am surprised at Dr Paula Mitchell remark stressing that fatigue cannot be self-assessed. I would agree with a statement that the impact of low level fatigue on performance cannot be sel assessed. The vast majority of people know when they are suffering significant levels of fatigue.
Most of my work has related to truck drivers and shift workers. I\’m not a fan of driving hours regulations for lots of reasons including:
1. Humans vary greatly in their degrading of performance with hours of work – some can work 16 hours/day 6 days per week for vary long periods without demonstrating a fatiue deficit. Others show deficits at 8 – 10 hours per day;
2 Natural influences like the circadian rhythm are independent of when people start work and their hours of work;
3. Other factors can negatively influence fatigue – a small amount of alcohol, a heavy meal, onset of a virus …
3. Driving hour regulations require a driver to have their first rest after 5 hours – yet research shows most near misses and crashes caused by fatigue occur in well under 5 hours;
4. Excellent research by Dallas Fels of NSW RTA showed most onroad fatigue caused near misses and crashes were experienced by the drivers of cars and other light vehicles when the time of travel was \”controlled\” by external factors – for example travel to work or fixed appointments, and travel home after work – very few incidents related to long distance work or holiday travel; and
5. Driving hours regulations do not require a driver show signs of being fatigued – they can be fined even though they are completely alert.
And I am against the sleep deficit algorithms that have been promoted because they have been shown to not accurately predict whether a person is fatigued at a particular time. I was invovled in a legal case where a truck driver went to goal for two years for two culpable driving fatalities based on the expert sleep deficit algorithm advice from two of Australia\’s fatigue experts. I was asked to assist when the driver on completing his 2 year sentence was presented with a $268,000 bill by TAC (TAC was recovering the money they paid the family of the two children killed). I showed that fatigue had nothing to do with the crash – in fact I would assert it was patently obvious fatigue had nothing to do with the crash.
My recommendation for any employer is as follows:
1. Recognise that people cam become fatigued and encourage employees and their workmates to report fatigue and take action to deal with it without any penalty;
2. Where employees work alone – for example truck drivers – require them to phone in when fatigued and take required rest/ sleep, while taking action to inform customers the driver would be late because he was doing the responsible thing to deal with fatigue; and
3. Where employees were to be invovled in special celebrations that were likely to cause them to be fatigue impaired (or subject to other impairment) adjust work schedules to accommodate that situation.
i have reguarly done 15 hour shifts over the years. i have neverhad a drink. I am a professional driver. i have never had an accident at night. i wonder what WORKSAFE VICTORIA is doing about all those taxi drivers it insists should carry their injured workers.
Mark, you may want to express your concerns to the taxi industry inquiry being undertaken at the moment by Alan Fels. Details can be found at http://taxiindustryinquiry.vic.gov.au/
I believe the concern around fatigue is a big issue. But to focus the primary responsibility on employers for managing it I think is fraught with danger.
Surely the approach of segregating ‘occupational fatigue’ cannot be an adequate approach when it is not possible to segregate a life into occupational and non-occupational components – fatigue is an overall issue of lifestyle and is affected by a wide range of contributing factors.
Sure, employers can manage the workload, shift hours, shift patterns etc. But at the end of the day, an employee has far more control of their life across the full 24 hours.
How can an employer be held accountable when they cannot ensure that an employee goes to bed to obtain sufficient sleep to minimise fatigue? Or how can an employer ensure an employee maintains a good diet and that their non-work life is not filled with stressors that contribute to emotional and mental fatigue, much less physical fatigue? Including the propensity for an individual to work more overtime (or second and third jobs) than they are really capable of doing safely because they are stressed about financial choices they’ve made and need to work long hours to pay off their debts?
At what point do we place an obligation on an employee to take responsibility for their lifestyle choices and insist that they present for work in a suitable condition to fulfil the obligations of their contract of employment?
I’m interested to note that the initial article states that “The first revelation in the seminar came from Dr Paula Mitchell who stressed that fatigue cannot be self-assessed”.
Maybe one approach for self-assessment, similar to one used by some employers for self-assessment of alcohol, would be to establish some basic ‘competency’ activities that measure such things as decision making, response and reaction times, visual perception, etc. It is quite reasonable that even such simple things as computer ‘games’ can be used to measure such indicators.
Again, because each workplace, and each job within a workplace, will have differing standards for these factors, it may be difficult to establish appropriate baselines for the ‘standard’ but it is feasible that such factors can be established and thence monitoring systems developed.
Once established it would be a simple matter of each mployee ‘taking the challenge’ to assess their ‘fitness for work’ (or as the article puts it – their level of impairment). And quite feasible that such an approach could be applied at various stages throughout a working shift to monitor ongoing fitness or increasing impairment.
It\’s interesting the note the links between being awake for prolonged period of times and being impaired by alcohol. Being awake for 17 hours is equivalent to a BAC of .05% whilst 23 hours is .1%. Being fatigued is like being drunk and has symptoms of slower reaction times, poorer co-ordination, falling asleep etc etc.
For many years they have been trying to invent a breathalizer for fatigue but none have been conclusive on their ability to measure it objectively (eg. Fit2020 was popular in mines in 2000 and most recently Eyecheck claims to be able to measure).
Fatigue being an invisible is often underestimated as a risk. Really anyone working shiftwork really requires regular fatigue management training.
Regards
Brendan Torazzi – CEO
AlertForce
Brendan, the comparison of fatigue with a blood alcohol content has been used for many years. I would say too many. The BAC comparison is an attempt to explain fatigue in an easily understood comparison. I understand the correlation conceptually but it won\’t change behaviour.
I have written elsewhere in the SafetyAtWorkBlog about the traps of comparing workplace health and safety with road safety. The comparison brings too much baggage and too many assumptions from road safety but I will apply Dr Miller\’s comment that the capacity for a person to determine their own level of fatigue is like determining one is okay to drive when drunk – impossible.
I think this 2000 article focussed on fatigue whilst driving is interesting but of far more relevance is gained through fatigue studies at workplaces.