Dead tired

Workplace fatigue can be fatal, and in a industry that is inherently dangerous it is essential that employers and employees know the signs of fatigue and the solutions to problems that arise from a lack of sleep.

We all know what it’s like to feel tired at work – it’s been a busy couple of weeks with a bunch of late nights thrown in and soon it’s getting harder and harder to drag yourself out of bed in the morning.

Shift work is another cause of workplace fatigue. Those jobs that have to be done during the night can be a huge cause of fatigue.

But seriously, excessive fatigue can be very dangerous – it can impair strength, speed, reaction time, co-ordination, decision making and balance. And it can have a long-term affect on health.

According to an article by the Department of Labour, ‘Managing Shift Work to Minimise Workplace Fatigue’, on average, shift workers lose one to one-and-a-half hours of sleep for each 24 hour period, and this builds up a sleep debt of six hours after four nights. Working more than three or four night shifts in a row causes a significant sleep debt, with serious consequences for safety.

How serious?

Errors made by shift workers in the early hours of the morning were critical factors in the nuclear plant disasters at Three Mile Island and Chernobyl, the deadly gas leak from the Union Carbide factory in Bhopal, as well as in the Exxon Valdes oil spillage. Fatigue can have serious consequences for public safety, as well as for the workers involved, in one-off events like these.

A New Zealand study has shown that one in four truck drivers is tired even before they begin their shift. And 24 percent of the drivers in the study failed a standard computer test of their ability to steer, keep to speed, cope with wind gusts, and notice and respond to signals.

Shift work is not the only culprit behind fatigue; long work hours – more than eight hours a day – can lead to employees getting less sleep than they need.

Not only does fatigue increase the chances of accidents, it is shown to affect health. Fatigued people feel less well, less alert and more tired and suffer from increased injury rates, more illness and increased mortality.

Obviously this affects the success of your business as accident prone and absentee workers are of limited benefit. Even when they are at work and not injuring themselves, fatigued workers will perform at a lower level and at a slower pace.

The contracting sector is a busy one, with odd hours at times, but it is in everyone’s interest – the employee, the employer and the public – that the issue of workplace fatigue is addressed.

On average, we need between seven and nine hours of sleep a night for consistent mental and physical recovery from daily activities. Getting sleep is the only way to recover from fatigue. Sleep patterns and working time preferences differ from person to person – some of us are early birds and others are night owls, but most people need six hours of unbroken sleep in any 24 hour period to remain alert (assuming a zero sleep debt).

The human body is programmed to be awake during the day and asleep at night and the body clock seldom adapts to shift work. Shift workers try to override the body clock to remain active at night when the body wants to sleep and to sleep when the body wants to be active. As a result they may be working when they are at the least functional and most error-prone, and not getting enough sleep between shifts to recover fully.

Generally speaking, most people naturally fall asleep somewhere between 10pm and 11pm, there is a period of wakefulness before this, from around 6pm to 10pm, when it is difficult for most people to fall asleep. It is also difficult to fall asleep when the internal drive reaches its daily peak – late morning for most of us, so when planning shift work, it’s preferable to avoid shifts that require workers to try and fall asleep at these difficult times.

When employees are working the night shift or long hours, taking breaks is essential – workers should take regular breaks from sustained work before their performance starts to suffer and fatigue sets in.

So how much time do people need to recover from fatigue?

Sleep loss is cumulative. As the pattern of shift work or long hours continues, the effects of sleep loss and poor quality sleep accumulate. Two full nights of unbroken sleep within the normal self-selected sleep time of 10pm to 8am, with a normal day in between, are a minimum requirement for adequate recovery after periods of long overnight work.

Good education about fatigue is important to minimise the problems associated with workplace fatigue. Employees should be given the tools to improve the quality of their life and sleep – such as how to make the most of their breaks, how to improve their sleep facilities and avoiding caffeine or alcohol within the hours before sleep, along with the knowledge on how to recognise fatigue.

A full copy of the guide ‘Managing Shift Work to Minimise Workplace Fatigue’ is available on the Department of Labour’s website: www.dol.govt.nz.