According to studies conducted by occupational health institutes, rapid shift rotation is good for both workers as well as employers. Experience in many different fields has shown that workers especially in older age groups benefit from shifts that rotate after two days or even one day. Speeding up rotation has been found to improve workers’ wellbeing and ability to enjoy leisure, provided the rotation is clockwise. The new shift system also improves work efficiency and quality.
"Speeding up rotation has led to the desired results. It has also achieved the most important objective, since shift workers’ wellbeing has improved," says Dr Mikko Härmä, who is a research professor at the Finnish Institute of Occupational Health. A series of studies conducted in cooperation with employers, workers and occupational safety and health authorities has shown the positive results of speeding up rotation, and everyone who has tried the new shift system or already adopted it has confirmed these results.
Since the beginning of the 1990s the Finnish Institute of Occupational Health has studied the effects of ageing on the ability to adjust to shift work. In the beginning all attention was drawn to differences between younger and older workers.
"Since older workers in particular were found to suffer in many ways from shift changes and especially night shifts, we started looking for new options. As studies progressed we discovered that adjusting to several night shifts in a row caused problems and older workers particularly had difficulties sleeping after night shifts. Their alertness also fell when they had to work several nights in a row," Dr Härmä explains.
"While occupational health and satisfaction have developed in a positive direction, balancing work and family life has also been easier. Alertness and work performance have improved. And best of all, the effects can be observed particularly among older workers." Studies have shown that older workers benefit the most from rapid shift rotation, Dr Härmä adds.
"Both laboratory and field studies have confirmed that it is not easy for people to adjust to several night shifts in a row. Fatigue accumulates with time and sleep loss weakens alertness and the quality of private life. For example, workers in the paper industry become over-strained if they do four consecutive night shifts. After two night shifts workers can recover faster and easier than after four night shifts." Dr Härmä adds that workers can get more out of their leisure time after only two nights on the job. "Activity and mood are clearly better."
After the Finnish Institute of Occupational Health published its first study on the effect of shorter shift rotations a couple of years ago, companies in the metal and engineering and chemical branches began speeding up shift rotation according to the new model.
"According to experience, workers consider a system with two consecutive shifts better than one with four consecutive shifts. Since speeding up rotation has not been found to increase costs, there have been no obstacles to adopting the new system." Dr Härmä thinks that the change has also been received positively because clockwise rotation leaves also between shifts free time for recovery.
Most recently the Finnish Institute of Occupational Health studied the matter in authentic working conditions in Finnair’s aircraft maintenance, where shift work had resulted in numerous early retirements. The trial went even further, with workers doing one morning, evening and night shift in succession. The findings, which will be published soon, were more positive than in any previous study of rapid shift rotation. Dr Härmä admits he was surprised to hear no negative opinions. "No one in the trial wanted to return to the old shift system."
The latest study also confirms that the employer benefits in many ways from speeding up shift rotation. "Besides the fact that operative working time is more effective, a worker who is more alert and happier on the job does better work. With improved occupational health, absences due to illness can be expected to decline. This means that skilled and experienced workers can stay on the job longer."
A research team at the Finnish Institute of Occupational Health will continue to rapid shift rotation under Dr Härmä’s leadership. "With the help of trials we can collect additional positive results and ensure effectiveness in different fields. The fact that the paper industry can now speed up rotation will also promote an important public health matter. Every measure that can prevent chronic illnesses and accidents associated with shift work is welcome."
Dr Härmä, whose area of expertise is working hours and sleep, believes that promoting work capacity and occupational health will produce results in the future as well.