Fatigue is particularly common among those working abnormal hours, including crews working on productions and can also arise from excessive working time. It is also related to workload; in that workers are more easily fatigued if their work is fast-paced, complex or monotonous.
A significant cause of fatigue is the amount and quality of sleep an individual receives, and crews working over night are particularly at risk because their day sleep is often lighter, shorter and more easily disturbed due to daytime noise and a natural reluctance to sleep during daylight.
There are a range of cognitive, physiological and emotional symptoms of fatigue, including poor decision-making, tiredness and lack of motivation, which can lead to workplace accidents.
Closely linked to fatigue, and perhaps its most significant cause, is the amount and quality of sleep an individual receives.
Work-related factors may include long working hours, poorly designed shift patterns, excessive stress, repetitive or monotonous jobs or the workplace environment (e.g. lighting, ventilation, temperature etc).
Medical conditions or personal factors may also be a cause of fatigue.
Job performance may be poorer on shift work especially when working night shifts. Tasks tend to be completed more slowly at night, although this can be balanced by altering the workload. In general the early hours of the morning, e.g. between 02.00 and 05.00 present the highest risk for fatigue-related accidents.
Sleep loss can lead to lowered levels of alertness. Cumulative sleep loss over a number of days can result in a ‘sleep debt’ with much reduced levels of productivity and attention. Such sleep loss results not only from working night shifts but also on morning shifts with very early start times and from ‘on call’ situations where it may be difficult to plan when to sleep.
Sleep helps us to recover from mental as well as physical exertion, and is vital for maintaining good mental and physical health. The relationship between sleep, physical health, and mental functioning is therefore difficult to overstate.
In 2002, Gary Hart was jailed for five years after dozing off on the M62 motorway when driving a Land Rover and trailer, ending up on a railway line and de-railing a passenger train, which was then struck by a freight train coming in the other direction, killing 10 people including the two train drivers.
In 2006, the Company was fined £30,000 plus £24,000 costs after one of its employees died when his vehicle drifted into the path of an oncoming lorry on his commute home. Although the commute to and from work was always regarded as being outside of working hours in the past, and therefore was not covered by any health and safety legislation, his employers were prosecuted under the Health and Safety at Work Act 1974 and the Management of Health and Safety at Work Regulations 1992. He had worked 76 hours in the previous four days and chronic fatigue is believed to be a major factor.
Employers have a legal duty to manage risks associated with fatigue and sleep loss under the Health and Safety at Work etc Act 1974, with the Management of Health and Safety at Work Regulations 1999 being the main instrument for risk assessment and management systems to control such risks.
The legal duty is on employers to manage risks from fatigue, irrespective of any individual’s willingness to work extra hours or preference for certain shift patterns for social reasons. Compliance with the Working Time Regulations alone is insufficient to manage the risks of fatigue.
Changes to working hours need to be risk assessed. The key considerations should be the principles contained in HSE’s guidance. Risk assessment may include the use of tools such as HSE’s ‘fatigue risk index’.
Employees should be consulted on working hours and shift patterns. However, note that employees may prefer certain shift patterns that are unhealthy and likely to cause fatigue.
Fatigue can be managed through policy, using tools to design shift patterns (e.g. the HSE’s Fatigue Risk Index), and promoting awareness and education of fatigue.
Take into account early starts, shift length, rest periods, shift rotation, social considerations and environmental factors.
Offer a health assessment to those who work at night, which is a legal duty under Working Time Regulations.
Provide awareness and education around fatigue and sleep deprivation as part of wider employee well being initiatives.
Fatigue can lead to errors and accidents, ill health and injury, and reduced productivity. It is often a root cause of major accidents e.g. Herald of Free Enterprise, Chernobyl, Texas City, Clapham Junction, Challenger and Exxon Valdez.
Fatigue has also been implicated in 20% of accidents on major roads and is said to cost the UK £115 - £240 million per year in terms of work accidents alone.