(29.05.2000 - Juhani Artto) The proportion of working hours other than regular Monday to Friday day work increased clearly in Finland in the 1990s. This is shown by a 1997 study conducted by Statistics Finland.


by night (%)

on saturdays (%)

on sundays (%)





















Wage and salary earners working between 11 p.m. and 6 a.m., or on Saturdays and Sundays at least once during the last four weeks.

According to the study, more than one fifth of wage and salary earners worked in shifts, men more than women and younger employees more than those over 45 years of age.

29 per cent of all employees were engaged in shift work or in other forms of work with unsociable hours.

While wage and salary earners worked an average of 1,687 hours per year, the self-employed and their family members exceeded this hugely with 2,316 working hours annually.

These figures and changes demand that serious attention be paid to the health impact of unsociable working hours. The Finnish Institute of Occupational Health recently published a summary of several studies made on the subject in Finland.

There is no lack of scientifically justified recommendations on how work schedules would be organised if the biological nature of working men and women were to be given full respect.

In contemporary working life, characterised by stiffening competition between commercial enterprises, the question is one of what kind of compromises are reasonable from the point of view of employers and, on the other hand, from that of employees. Many mistakes can be made, damaging both individuals and enterprises.

Increased risk of industrial accidents

One problem with unsociable working hours is an increased risk of industrial accidents. Various studies show that the accident risk on the night shift is 20 per cent higher than in other shifts where other factors remain equal. Night work becomes especially risky if the employee regulates the work tempo instead of the machine or process. This entails a doubling of risk. Another low alertness period is in the afternoon between one and five.

Work shifts exceeding eight hours also increase the accident risk. At the end of a twelve hour shift, the risk is twice as high as at the end of an eight hour shift.

Shift work increases the risk of coronary heart disease by 40 per cent. This conclusion originates from more than ten epidemiological studies made mainly among industrial workers.

Chronic tiredness, nervousness and low spirits are also more common among shift workers than in other employee groups. However, there is no evidence that shift work causes a higher risk of serious mental illnesses such as depression.

Increasing age means lower body adaptability to night work. While the first night shows no age-related differences, in subsequent consecutive night shifts older workers get tired more easily than their younger workmates.

Nowadays, too little sleep at night - often due to overtime work or unsociable working hours - is very common. Lack of sleep is twice as common among working people than among the unemployed and pensioners. Tiredness, naturally, results in impaired job performance.

Shift work also has a negative impact on the reproductive health of women. The menstrual period becomes more irregular and fertility decreases.

The mental power of deduction and the ability to perform mental arithmetic decrease after the first eight hours of work.

Health not the motive for working hour experiments

How much attention is paid to these biological facts when increasing unsociable working hours? "Little if any" would seem to be the answer. This is the common experience of working men and women common all over the world. The pressure for more shift and weekend work originates in the need to increase the running times of machines and processes and to respond in a more flexible way to consumer and market demands.

Globalisation of the economy adds to these pressures as fewer industries are protected from foreign competition while deregulation also intensifies domestic competition. As employees are forced in many cases to pay a high price for changes in work schedules - in the form of industrial accidents and health problems - at a certain point such changes become counterproductive for enterprises as well.

This means that employers would be wise to allow both medical specialists and workers' representatives to have their say in work schedule management. This could result not only in fewer industrial accidents and health hazards, but also in improved productivity.

Interestingly, the latter has already been demonstrated in a few pilot projects in which employers and employees have experimented with varying working hour models.

One tenth of all employees have participated in so-called working hour bank experiments. Far fewer have experience of other alternative forms such as the 6 + 6 hour model, subsidised part-time work or job rotation. One employee in sixteen has participated in trials of the so-called compressed working week. One model of this meant three twelve-hour working days per week.

The starting point for these experiments, however, has hardly ever been the need to protect the health of workers. Other motives, such as willingness to increase capacity utilisation rate and employment, have made employers and employees able to find a common interest in improving work schedules.