Work shift recommendations reduced occupational accidents in social services of cities by 20 per cent

The Finnish Institute of Occupational Health's Working Time Traffic Light Recommendations have been included in the shift planning of various cities and hospital districts across Finland with good results. The five-year follow-up study shows that the recommendations have reduced stress related to working time. Occupational accidents among employees in the social and health care services of cities decreased by 20 per cent.
Lääkäri ja hoitaja katsovat tietokoneen ruutua.

Finnish Institute of Occupational Health media release, 9 November 2022

Stressful work schedules are known to increase the risk of occupational accidents, cardiovascular disease and breast cancer in the social and health care sector. The stress related to shift work can, however, be reduced by proper shift planning.

The Finnish Institute of Occupational Health’s Working Time Traffic Light Recommendations that support good shift ergonomics have been part of shift ergonomics evaluation tool in the Titania® shift planning software since 2015. The most recent study, published today, examined the impact of checking shift ergonomics on occupational accidents.

Cities experienced fewer occupational accidents thanks to the recommendations

The dataset comprising of nearly 30,000 social and health care employees included a total of 4,102 occupational accidents during 2015–2018. Those who had inspected their shift ergonomics according to the Working Time Traffic Light Recommendations had fewer dislocations, sprains and strains related to falls.

In cities that spent more than three times as much time on inspecting shift ergonomics as in hospital districts, the number of occupational accidents occurring during working time was nearly 20% lower for those who put shift ergonomics in order. Occupational accidents caused by falling or slipping were 25% less frequent than for those whose shifts had not been inspected according to the traffic light model. The multivariate model took into account differences between groups in terms of age, gender, employment, night work and the use of different types of shift planning software.

“We also studied the pathways reducing the risk of accidents. They were most closely related to increased recovery, such as having extra days off between shifts or reduction of long night shifts”, says Senior Scientist Rahman Shiri from the Finnish Institute of Occupational Health.

“The link between recovery and occupational safety may be related to longer sleep. In another study published this year, we found that shorter periods of sleep increase the number of occupational accidents related to falls,” says the project’s leader Mikko Härmä, Research Professor at the Finnish Institute of Occupational Health.

The use of the Working Time Traffic Light Recommendations has become more common in social welfare and health care services

The Finnish Institute of Occupational Health also investigated the prevalence of the use of Working Time Traffic Light Recommendations and their impact on working time characteristics in Finland. The recommendations have been part of shift ergonomics inspection tools in the Titania® shift planning software since 2015.

The results show that shift planners regularly inspected and corrected shift ergonomics according to the recommendations of the Finnish Institute of Occupational Health in 20% of the total dataset (over 36,000 employees) during 2015–2019, but at least in one 3-week shift plan, almost everyone (96%) was inspected.

Compared to those who did not use the inspection tool, the regular correction of shift ergonomics reduced short intervals between shifts, long shifts and night shifts, which are particular causes of health hazards in shift work. Individual days off increased and consecutive shifts became less frequent.

In cities where more time was devoted to inspecting shift ergonomics than in hospital districts, the number of long work shifts decreased additionally, and the recovery periods after night shifts became longer.

“The Working Time Traffic Light Recommendations can clearly reduce stressful working hours if the recommendations become part of the shift planning process,” says Research Professor Mikko Härmä. “However, the organizations' own commitment to work shift planning in order to support occupational health is essential.”

One of the target organizations of the project, the City of Helsinki, has promoted good shift ergonomics for years, and shift ergonomics inspections are common in Helsinki's social and health care services.

“I think it is important to support well-being and mental health with better working time patterns. From a safety point of view, the most stressful shifts also need to be reduced,” says Sari Kuoppamäki, Manager of Human Resources at the City of Helsinki.

Shift work increases health risks in the social and health care sector

Intermittent work in the social and health care sector is often shift work, which involves evening and night work and irregular working times. The recovery times between shifts are often too short. The Finnish Institute of Occupational Health has carried out a lot of research concerning the health risks associated with shift work. For example, studies published this year show that shift work doubled the risk of breast cancer in women aged 50 and over in the social welfare and health care sector. Second, frequent night shifts increased the risk of both coronary artery disease and cerebrovascular diseases. It has been known earlier that shift work increases the risk of sickness absences and occupational accidents.

Learn more

Recommendations of the Working Time Traffic Light model for the assessment of stress related to working time (in Finnish)

Working time in the social affairs and health care sector (tyoelamatieto.fi)

New research data on the health effects of shift work – researchers have updated their recommendations | Finnish Institute of Occupational Health (ttl.fi, in Finnish)

People over 50 years of age should be offered the opportunity to reduce night shifts and long hours | Finnish Institute of Occupational Health (ttl.fi)

Research articles

Shiri R, Turunen J, Karhula K, Koskinen A, Sallinen M, Ropponen A, Ervasti J, Härmä M. The association between the use of shift schedule evaluation tool with ergonomics recommendations and occupational injuries: A 4-year prospective cohort study among health care workers. Scan J Work Environ Health, published online 2022: https://www.sjweh.fi/article/4068

Alhainen M, Härmä M, Pentti J, Ervasti JM, Kivimäki M, Vahtera J, Stenholm S. Sleep duration and sleep difficulties as predictors of occupational injuries: a cohort study. Occup Environ Med. 2022 Apr;79(4):224-232: https://pubmed.ncbi.nlm.nih.gov/34650000/

Bigert C, Kader M, Andersson T, Selander J, Bodin T, Gustavsson P, Härmä M, Ljungman P, Albin M. Night and shift work and incidence of cerebrovascular disease – a prospective cohort study of healthcare employees in Stockholm. Scand J Work Environ Health. 2022 Jan 1;48(1):31-40. doi: 10.5271/sjweh.3986: https://www.sjweh.fi/article/3986 

Härmä M, Shiri R, Ervasti J, Turunen J, Koskinen A, Ropponen A, Sallinen M. National recommendations for shift scheduling in healthcare: A 5-year prospective cohort study on working hour characteristics. International Journal of Nursing Studies 2022, 134, 104321: https://pubmed.ncbi.nlm.nih.gov/35905662/

Härmä M,  Ojajärvi A, Koskinen. A,  Lie J-A, Hansen J. Shift work with and without night shifts and breast cancer risk in a cohort study from Finland. Occup Environ Med 2022 Aug 10;oemed-2022-108347: https://pubmed.ncbi.nlm.nih.gov/35948413/  

Kader M, Selander J, Andersson T, Albin M, Bodin T, Härmä M, Ljungman P, Bigert C.  Night and shift work characteristics and incident ischemic heart disease and atrial fibrillation among healthcare employees - a prospective cohort study. Scand J Work Environ Health. 2022 Sep 1;48(7):520-529. doi: 10.5271/sjweh.4045: https://pubmed.ncbi.nlm.nih.gov/35723926/ 

For more information, please contact

Mikko Härmä, Research Professor, Finnish Institute of Occupational Health, tel. +358 (0)40 544 2750, mikko.harma [at] ttl.fi (mikko[dot]harma[at]ttl[dot]fi)

Rahman Shiri, Senior Scientist, Finnish Institute of Occupational Health, tel. +358 (0)30 474 2998, rahman.shiri [at] ttl.fi (rahman[dot]shiri[at]ttl[dot]fi)

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