Sleep well and stay safe

Sleep deprivation is a major factor behind many work-related incidents and traffic accidents.

In 2014, Uehli et al. concluded that up to 13% of work-related injuries were associated with sleep problems. Although the risks affiliated with poor sleep have been understood for a while, fatigue, or tiredness, and the issues relating to this, continue to increase.

There are many reasons behind the numbers; a disregard for the ‘value’ of sleep, increased stimulation caused by our ‘always-on’ lives in the digital age, and changes in the modern lifestyle and habits of people in general. Yet, irrespective of the reasons behind this increasing lack of sleep, it is now obvious that many of us do not get enough rest and recovery from our day.

With a very simple calculation, it could be argued that for working-age humans, on average, one third of the day is spent at the workplace, one third in leisure-time activities and one third sleeping. But life, however, is not nearly this inflexible and structured for most of us, and the listed activities often overlap each other in a number of ways. Additionally, several studies have indicated that the time we allocate for sleep has decreased over recent decades, although our physiology has not adapted to overcome this.

At work, fatigue, often resulting from sleep deprivation and/or poor quality of sleep, is a source of risk. Lack of sleep can influence both the individual worker’s health, safety and wellbeing, as well as also jeopardise the company’s operations, as reliability decreases and the number of errors and mistakes increase, for example.

Fatigue as a part of human performance

Human factors could arguably be viewed as a synonym for ergonomics, which combine the physical, cognitive and organisational factors that influence human performance. Human factors refer to all the technical, workplace and individual characteristics, alongside organisational matters, which have an impact on our behaviour and performance. These sciences, in effect, study human performance and the factors that allow us to succeed, or indeed fail, in various situations.

In recent decades, it has become increasingly clear that failures in human performance are behind many accidents. In popular contexts, human error has often been named as the cause of an accident, rather than a technical malfunction or system breakdown. Human error has also been commonly perceived as something that ‘just happened’ and is thus difficult to predict or control. Within this context, fatigue is a good example of a factor which can contribute towards many kinds of incidents occurring.

Fatigue itself does not cause accidents, as such, but it can have a remarkable influence on the way we perform. Together with task complexity and/or distracting factors in the operating conditions (such as noise pollution), fatigue can be a major contributing factor with regards to igniting a chain of events that will eventually lead to an accident. 

According to Sawatzky (2017), there are four main ways in which fatigue impairs performance:

  1. Alertness – It is normal that our alertness levels vary naturally throughout the day, and often we do not even notice it. They simply happen, whether we feel tired or not. However, fatigue makes it even more difficult for people to remain alert, recognise or notice abnormalities, as well as impairs their reaction time to any changes.
  2. Emotional stability – In critical situations, fatigue often impairs our ability to remain emotionally calm and stable. Also, aggressive behaviour and depression may become more common when we feel tired and/or are sleep deprived.
  3. Mental ability – Fatigue, and sleep deprivation in general, impairs our ability to think, remember and communicate clearly.
  4. Physical ability – Fatigue leads to a lowering of reaction times and coordination. Micro-sleep, which can be defined as a sudden, uncontrollable and very temporary episode of sleep, lasting from fractions of a second up to around 30 seconds, also belongs to this group: microsleep poses a major risk for health and safety, for example in traffic or in the work environment.

Considering the above, it is clear that fatigue can have a negative impact in the workplace, both from the perspective of operational reliability, as well as from a health and safety perspective, and can put employees at risk. A typical mechanism behind fatigue-related accidents is, for example, risk taking or losing one’s focus of attention.

This applies to both knowledge-intensive work and manual work: the more attention demanded by a task, the more important it is to remain alert and focused when executing the task. If this focus is lost and the employee is not able to concentrate sufficiently when performing a safety-critical task, it becomes clear that the risk of an incident or accident will increase. To support safe and smooth operations, employees must therefore be able to focus on their tasks successfully.

Fighting fatigue

As Sawatzky (2017) notes, both fatigue and fatigue-related risks should be assessed as a part of workplace risk management. The assessment should cover the risks from different perspectives, including those that target the employee. To aid the assessment, questions that require answering should include: how does fatigue influence an employee’s wellbeing and workability? Which tasks are safety-critical? What happens if these tasks are done without the required alertness? Can a failure to concentrate on these tasks lead to a major loss or injury?

It is important to conduct regular trainings and risk assessments of complex and safety-critical tasks, in addition to promoting the correct working methods. This way, employers can help their employees execute the procedures correctly, even if the employees are sleep deprived.

Generally, people believe that fatigue is commonly affiliated with strenuous, intensive tasks. However, an incident or accident is more probable in those tasks that are monotonous or perceived to be lacking in stimulation, or simply ‘boring’. In such cases, sleep deprivation can easily lead to lowered alertness and drowsiness.

Are there any tasks that may include a bigger risk of fatigue?

A good practice for employers is to raise awareness of the importance of sleep. Making sleep a priority is a matter of employee wellbeing that will also indirectly improve loss prevention and safety at work. (Source: CDC, Workplace Health Resource Center, 2021)

Removing excessive audio-visual distractions, improving ergonomics and the usability of tools, as well as having clear guidelines and procedures, will help reduce the number of incidents, accidents and losses that relate to human factors, and reduce the risk of human error. This was also confirmed by the Finnish Institute of Occupational Health (2015) in an extensive study focusing on the reduction of human errors at workplaces. These same features can help employees to make the correct actions at the correct point of time, even when feeling tired.

From the perspective of an individual employee, it is important to take breaks throughout the workday. During physically demanding tasks, our body needs regular breaks so that we can continue working. The same rule applies to our brain: in knowledge-intensive work, breaks help our brain to recover, just like our muscles need to restore themselves following the completion of arduous tasks. The recovery of the human body during leisure-time is the cornerstone of wellbeing, and the importance of getting enough good sleep should not be underestimated. 

In addition to understanding the importance of getting good sleep (both quantitively and qualitatively), it is now more clearly understood that we also need recovery breaks during the workday. These should be an inherent part of our routines in the work environment, be they coffee breaks, taking a walk outdoors, or taking a so-called ‘power nap’ if required.

Moreover, we should bear in mind that neglecting breaks is not only bad for our wellbeing, it can also risk injury or failure to complete the tasks we are responsible for. Taking care of ourselves is also about being able to perform at our best.

Best practices for companies

  1. Promote health and wellness through internal campaigns and activities regularly
  2. Review employee workstations and the office environment regularly for lighting, ergonomics, as well as noise distraction.
  3. Highlight the importance of nutrition, sleep and wellbeing in your corporate culture.
  4. Remember to encourage employees to take breaks and conduct walking meetings when possible.

The challenge of shift work

Shift work, including working at night, is a common mode of employment in many industries. Nightshifts, and shift work in general, can cause issues that disrupt sleep and recovery. This relates to maintaining a regular sleep rhythm, for example, which may be further reflected in poorer sleep quality.

Nightshifts can also lead to psychosocial issues, due to the opposing day rhythm, potentially causing increased work stress and burnout. These factors together highlight the importance of finding ways to reduce and prevent the pressures of performing work duties during the night.

If’s client, Vaasan, a Finnish bakery company, initiated a study in their bakeries, which aimed to investigate whether sleep quality was related to psychosocial stress among workers doing night shifts. The research also studied whether regular sleep rhythms and segmented sleep on workdays and days off were related to sleep quality and psychosocial stress.

The study, conducted by Matias Ovaska in 2020, highlighted that good sleep quality and sleeping without interruption or breaks is associated with reduced psychosocial stress. This result is consistent with previous studies in which sleep quality and psychosocial stress are strongly correlated. In his thesis, Ovaska concluded that “Ensuring good sleep quality is one of the most important countermeasures to prevent the adverse effects of night work.” Although the framework for study was bakeries, the results of this study can be utilised in other industries that include regular night work.


Kalakoski V., Ratilainen H., Puro V., Perttula P., Salminen S., Lukander J., Mattila S., Leskinen T., Mäkelä T., Plaketti P. (2015). Better workflow, less errors: Decreasing human errors at work, the SUJUVA project. Finnish Institute of Occupational Health. Available: Sujuvaa työtä vähemmän virheitä.pdf (

Ovaska, M. (2020). The association of sleep quality with psychosocial stress in night workers. Faculty of Sports Sciences, University of Jyväskylä. Master’s thesis in Gerontology and Public Health, 38 p., (3 appendices).

Sawatzky, S. (2017) Worker fatigue. Understanding the risks in the workplace. Professional Safety, November 2017.

Uehli K., Mehta A.J., Miedinger D., Hug K., Schindler C., Holsboer-Trachsler E., Leuppi J.D., Künzli N. (2014). Sleep problems and work injuries: A systematic review and meta-analysis. Sleep Medicine Reviews, Vol. 18 (1), pp. 61-73.

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