Fatigue management at work: causes and controls

Fatigue at work is a state of tiredness, from long hours, poor sleep, heavy physical or mental workloads, or hot and noisy conditions, that slows reactions and weakens judgement. Fatigued workers make more mistakes and take longer to react, which makes injuries more likely for them and for the people around them. Fatigue management means finding the causes in your workplace and putting controls in place, starting with the rosters and workloads that cause it.

This guide covers what causes fatigue, what it does to safety, and the controls employers use, along with the duties that apply under the WHS laws.

What is fatigue at work?

Fatigue is more than feeling tired. It is the physical or mental state that stops a person doing their job safely. Physically, it shows up as low energy, slower reactions, and reduced strength and coordination. Mentally, it shows up as poor concentration, memory lapses, slower decisions and reduced alertness.

It affects everyone, regardless of skill, experience or training. A highly trained operator can be just as fatigued as a new starter after a long run of night shifts.

What causes fatigue?

Fatigue usually has several causes working together. The most useful way to sort them is into four groups:

• Hours and rosters. Long shifts, extended hours without breaks, short turnarounds between shifts, and regular night work or early starts all add up.
• Sleep. Poor sleep quality, irregular sleep schedules and sleep disorders all reduce recovery. Sleep loss builds up over days, not in a single shift.
• Workload. Heavy lifting, repetitive tasks and prolonged standing create physical load. Constant decisions, high concentration, emotionally demanding work and a steady flood of messages create mental load. Both can drive fatigue on their own.
• Environment. Heat, noise, vibration and poor lighting make work harder, and they make concentration more difficult. A noisy workshop or hot roof can tire people faster than the task alone would.

Lifestyle factors also play a part, including multiple jobs, long commutes, family responsibilities and poor diet or hydration. You can't control these directly, but you can account for them in your rosters and by talking to workers about their situation.

Some groups face more risk than others. Shift and night workers, transport and FIFO workers, emergency responders, and people working long hours on construction sites are common examples. In hospitality, long and split shifts are a particular problem, as our hospitality hazards guide explains.

How does fatigue affect safety?

Fatigue harms people in several ways that matter on site:

• Accidents. Tired workers make more mistakes and react more slowly to hazards.
• Poor judgement. Fatigue affects decisions, so people take shortcuts or miss warning signs.
• Reduced coordination. This is especially dangerous when operating machinery or driving a vehicle.
• Health. Long-term fatigue, combined with stress and poor sleep, can contribute to mental and physical health problems.
• Motivation and quality. Fatigued workers struggle to stay focused, which can reduce the quality of the work and lead to more errors.

The model Code of Practice: Managing the risk of fatigue at work covers both the work and the people doing it.

What are your duties?

Under the WHS laws, the person conducting the business or undertaking (PCBU) must ensure, so far as is reasonably practicable, the health and safety of workers. That includes managing the risk of fatigue. The duty can't be transferred to someone else, even if a contractor or labour hire firm supplies the workers (section 14).

Workers also have duties. They must take reasonable care of their own health and safety and not adversely affect others. That means staying aware of their own hours and breaks, following your fatigue policy, and telling you when they're too tired to work safely.

Some industries have their own fatigue rules. Heavy vehicle drivers are covered by the national heavy vehicle fatigue rules, and aviation and rail have their own regimes. If your work falls under one of these, follow those rules as well as the WHS duties.

How to control fatigue

The Safe Work Australia guide for managing the risk of fatigue at work takes you through the process. Start with the causes, then choose controls near the top of the hierarchy of controls where you can.

1. Plan the rosters

Rosters cause most fatigue, so start there:

• Limit the number of consecutive night shifts, and give enough time off between them
• Keep shifts to a length that suits the work, and avoid unplanned extensions
• Avoid scheduling the most safety-critical tasks in the early hours or at the end of a long shift
• Give people enough time between shifts to sleep and recover
• Make rosters predictable, so people can plan their sleep and their lives

2. Manage the workload

Work that's too much for one person is a common cause of fatigue. Look at the tasks people do and how long each one takes:

• Structure the shift so the heaviest work comes at the start or middle, not at the end
• Set clear priorities, and make it easy for workers to tell a supervisor when the load is too much
• Share out tasks so no one carries the whole load
• Rotate people off the most physically or mentally demanding tasks

3. Provide proper breaks

Breaks matter more than most managers expect:

• Schedule regular rest breaks, and make sure people actually take them
• Let people move around during breaks, not just sit
• Encourage workers to use days off properly, and to get enough sleep between shifts

4. Change the environment

Heat, noise and poor lighting all add to fatigue. Where you can, avoid work in extreme heat, reduce noise, improve lighting, and provide shade and rest areas. Heat stress management covers the heat side of this in detail.

5. Support your workers

Fatigue often has causes outside work, such as poor sleep, stress and health conditions. Talk to workers about these in a supportive way. Offer employee assistance programs or other health resources, and flexible arrangements where the work allows. Encourage workers to see a doctor if they're tired all the time, since some health conditions cause fatigue.

6. Write a fatigue policy

A written fatigue management policy turns the controls into something everyone can follow. It should cover:

• Maximum shift lengths and minimum rest between shifts
• Required breaks, and how to take them
• How workers report fatigue, and what happens when they do
• Who makes decisions about fatigue on site, and what authority they have
• How you'll check the controls are working

The workplace fatigue management plan and fatigue risk assessment form in our library give you a starting point for the policy and the risk assessment.

7. Use technology where it helps

Some employers use fatigue monitoring software, scheduling tools that spread work evenly, or wearable devices that track sleep. These can help, but they don't replace good rosters and workloads. Check any tool for accuracy, and be clear with workers about what data is collected and why.

8. Train workers and supervisors

Training helps people spot fatigue in themselves and others:

• Explain the causes and effects of fatigue in plain language, in the languages your crew uses
• Train supervisors to recognise warning signs, such as slower work, errors and irritability, and to act on them
• Make sure night and relief staff get the same information as day staff

How do you identify fatigue hazards?

You can't manage fatigue you haven't found. Use a mix of methods:

• Consult workers. Ask about hours, rosters, the number of shifts in a row, and the tasks that wear them out. Health and safety representatives should be part of this.
• Look at records. Check sign-in and sign-out sheets, timesheets, and overtime or leave records for patterns.
• Review incidents. Look for near misses and incidents where tiredness may have played a part.
• Watch the work. Observe the shifts that are hardest, such as night work or the last hours of a long day.

Then assess the risk: how likely fatigue is to cause harm, and how serious that harm would be. If a fatigue risk is already well known and has established controls, put those controls in place rather than starting from scratch.

How do you review fatigue controls?

Controls need checking, because rosters, workloads and workers change. Review them:

• After an incident or near miss
• When the work, rosters or sites change
• When workers report that the controls aren't working
• On a regular schedule, with a clear owner

Use trial periods for big changes, so you can see what works before you commit. Ask workers for feedback, and use the data you already have to check whether fatigue is going down.

How SafetyDocs helps

SafetyDocs has expert-written fatigue templates, including a workplace fatigue management plan, fatigue risk assessment forms and a light vehicle driver fatigue form. You fill in the details for your workplace once, and workers sign on from their phone or a QR code. When the policy changes, everyone who signed the old version is asked to sign the new one, so the whole crew is working from the same rules. It helps you keep these records in order, but it doesn't make your workplace compliant on its own.

Common questions

Is fatigue a WHS issue? Yes. Fatigue is a hazard that can cause injury, so it falls under the PCBU's duty to manage risks. Ignoring fatigue doesn't remove the duty.

Can I just tell workers to take more breaks? Breaks are one control, but they rarely fix the cause. If the rosters or workloads are the problem, breaks alone won't be enough. Start with the cause, then use breaks as part of the solution.

What if a worker says they're too tired to work? Take the report seriously. Don't put pressure on them to keep working. Move them to a safer task, let them rest, or send them home, and then look at why it happened.

Does fatigue management apply to office workers? Yes. Fatigue affects everyone, and office work can cause mental fatigue, long hours and poor sleep. The same process applies, with controls suited to the work.

This is general information, not legal advice. Check the current law with your WHS regulator.