Fatigue can be caused by many factors. Often a number of factors combine to increase fatigue to the point where a person may put their own or another person’s safety at risk. As a result, both employers and employees have a role to play in making sure any risks associated with fatigue are minimised.

Evidence suggests that sleep deprivation, sleep disturbance and fatigue are health risks commonly associated with long working hours. Fatigue has also been identified as a potential health risk with work that involves shifts or regular or periodic night work and can lead to impaired physical and mental performance and therefore increase the risk of injury.

WorkSafe has a tool to use when considering working hour arrangements to help identify the potential risk of fatigue.  Potential risk factors associated with working hours arrangements include but are not limited to:

Working hours

• number of hours worked, e.g. average weekly hours; daily work hours and work-related travel; and scheduling of work;
• shiftwork, eg length of shift; time, speed and direction of shift; split shifts 
• night work, eg shift end (for those working eight hours or more between 10.00 pm and 6.00 am); length of shift; sequential shifts; and period of non-work following a sequence of night shifts 
• breaks during work, e.g. frequency of breaks;
• breaks between work periods, for example recovery time; and
• seasonal work arrangements, for example hours worked.

Demands of the work tasks – for example:

• repetitive work, for example inadequate variation of tasks (physical and/or mental) with excessive periods of repetitive physically or mentally demanding work;
• physically demanding work; and
• high concentration and/or mentally demanding work

Fatigue critical tasks – these are tasks where there are potentially increased risks of incidents,

• injury or harm should employees become fatigued, for example during operation of certain plant and/or making critical decisions where there may be significant consequences if errors occur

Extended exposure to hazards – for example:

• exposure to hazardous substances and atmospheric contaminants;
• exposure to noise;
• exposure to extreme temperature; and
• exposure to vibration.

Information and training – for example: 

• provision of information on fatigue management skills and health and lifestyle factors;
• provision of training on fatigue management and health/lifestyle factors; and
• training on job skills.

Supervision – for example its adequacy.

Individual and lifestyle factors – for example:

• sleep (amount and quality) in a 24 hour period;
• health, for example poor diet, recent illness/injury and sleep disorders;
• fitness for work ie presenting in a fit state for work; and
• lifestyle factors, for example activities or responsibilities that limit sleep such as a second job, family commitments and long commuting distance.

The hazards/hazard factors and risks may be inter-related and, in some cases, cumulative. 

In consultation with employees, employers must develop control measures to address the potential risk of fatigue arising from the working hours and demands of the work.

Related publications

• Code of practice: Working hours
• Risk management guidelines 
• Guide for managing the risk of fatigue at work (Safe Work Australia)