Job – related fatigue of shift workers

By Ásta Kristín Gunnarsdóttir

There are a number of aspects that can affect the alertness and capabilities of members of different professions, such as conditions for rest before a shift, family circumstances, working environment, staff health and their attitudes towards the work.

Work-related fatigue and lack of sleep

Although work-related fatigue may be found in 7–45% of professions, studies have shown that fatigue varies in severity depending on the nature and scope of the profession. Studies have, for instance, shown that night-time work results in more fatigue than day-time work. Staff who work night shifts sleep on average one to four hours less after their shift than day-time workers. The reason for this is that once the night shift ends and the time has come to sleep, light levels in the environment contradict the body’s daily rhythm and have a disruptive effect on the length and quality of sleep. In addition, the increased speed of and distractions in society have an impact on the duration of sleep and rest time, with studies showing that the general public’s length of sleep has shortened considerably in past decades.

The consequences of sleep deprivation

Difficulties in falling asleep, maintaining sleep and sleep deprivation are among the most common sleep problems among humans. It is believed that 20–40% of adults suffer from sleep problems. If sleep requirements are not met, a “sleep debt” is formed which needs to be repaid with a longer sleep period. Those who “owe sleep” usually repay it on a day off or on weekends. Some are able to get by with less sleep than others, although not much is known about the reasons why this should be so. Women, however, appear to tolerate lack of sleep worse than men. Studies have shown that attitudes toward the job, employees’ loyalty to their employers, free time, fatigue, sleep disruptions and social and family circumstances appear to be deciding factors. The consequence of sleep deprivation is decreasing alertness. We are most alert in the morning after a good night’s sleep; this then decreases over the course of the day and measures lowest at night between 04:00 and 07:00 in the morning. The greatest risk of mishaps and mistakes due to lack sleep and fatigue is during the latter part of the night. Numerous studies have shown that excessive tiredness following lack of sleep or disrupted sleep (for various reasons) manifests in the same manner as alcohol consumption or the intake of sedatives. After 17–19 hours awake, the level of fatigue can be the equivalent of 0.5% alcohol in the blood. In comparison, driving a vehicle in Iceland with a blood alcohol level of more than 0.2% is a punishable offence. This comparison of fatigue levels and blood alcohol levels has made people think hard about the seriousness of fatigue in professions with high degrees of responsibility. The fact that professions that work long and irregular shift work are more likely to have mishaps than other professions should be taken extremely seriously. Mistakes at work can have serious consequences.

What can be done?

Company management must pay attention to how the work is organised. This is best done by consulting the employees when organising shift rotas. This increases their sense of responsibility and work contribution. The best thing is to order work shifts according to the body clock so that the evening shift takes over from the morning shift and the night shift takes over from the evening shift. If this is done, the work shifts will rotate in tune with the sun’s cycle and not against it as is often the case. One of the best cures for fatigue is rest, and sleep is the best method to get rest. Numerous factors can prevent employees from achieving proper rest. Among these are family circumstances, especially if there are young children in the household; noise or poor facilities to rest once at home; physical wellbeing such as aches or worries; other responsibilities such as the care of aged parents; and last but not least, studies or an extra job that may prevent the employee from obtaining the requisite rest. Education on employee fatigue and sleep is important, as this can solve many problems, decrease the number of sick-leave days and prevent professional burn-outs. To achieve this, there needs to be dynamic and beneficial co-operation between employees and their employers.

Ásta Kristín Gunnarsdóttir is a nurse and a flight attendant.

, , , ,