14.0 Impairment

14.1 Introduction to managing impairment risks

This section offers guidance for persons conducting a business or undertaking (PCBUs) on managing the risks or impairment for road and roadside workers.

A worker’s fitness to work can be impaired by things like fatigue, medication, drugs, and alcohol. This can create a risk to their health and safety and the safety of those around them.

14.2 Fatigue

Road and roadside work relies on workers being physically and mentally alert.

Fatigue is a physiological state where someone is not able to mentally and physically function as they usually would. There are four main factors that can contribute to someone developing fatigue:

missing out on sleep
being awake for too long
working and sleeping in the wrong parts of the body clock cycle
having a high workload (mental and/or physical).

Fatigue is a major risk for road and roadside workers. Examples of conditions that can lead to road and roadside workers experiencing fatigue include:

the increase in 24-hour operations
longer shifts
an increase in overtime hours
on-call or night duties
long driving times (some workers have to travel before and after their shifts – particularly, to reach remote worksites or emergency response sites)
personal health or lifestyle factors.

As the level of fatigue experienced by a worker increases, there is a higher likelihood that the worker will experience impairment. This can affect their decision-making abilities, increasing the likelihood of negative safety or health outcomes.

Fatigue could also cause micro-sleeps, where the person briefly falls asleep. Micro-sleeps are potentially deadly if they occur at the wrong time – for example, when the person is in control of a vehicle or mobile plant.

14.3 Control measures for fatigue

There are several control measures that can be used to reduce the chances of workers experiencing fatigue, for example:

creating work schedules that allow for sufficient rest during work shifts and between shifts (create these in consultation with your workers)
making sure working hours are not too long. If longer working days are required, consult with your workers before deciding these hours. Consider staggered start and finish times, longer rest breaks, and periods off work
scheduling tasks suitably throughout a work period. A person’s ability to remain alert and focused can be reduced between 3.00am and 5.00am, and between 3.00pm and 5.00pm. If reasonably practicable, avoid critical jobs, such working at height, manual tasks, or tasks using mobile plant or vehicles, during these times
monitor and place limits around the number of overtime hours that can be worked. Avoid incentives to work excessive hours
monitoring and placing limits around shift swapping and on-call duties
designing rosters that follow natural sleeping rhythms and allow for good sleep opportunity and recovery time
avoiding work that starts before 6.00am, where possible. If night work is required, limit the number of night shifts in a row that your workers can work
factoring in travel times to worksites. Long travel times to remote worksites will contribute to fatigue, as will the effects of staying away from home for days at a time
checking that casual staff or labour hire workers have not recently worked a shift somewhere else (for example, the same day or the previous night). If they had, they might already be tired.

You can also manage the effects of fatigue by managing physical and mental work demands. For example:

limiting periods of excessive mental or physical demands by often rotating those tasks between workers
making sure plant, machinery, and equipment are fit for purpose
making sure workloads are manageable. Take into account workflow changes due to factors such as machinery breakdowns, unplanned absences, or resignations
avoiding unreasonable deadlines.

Consider seeking expert advice from a suitably qualified health and safety professional that specialises in fatigue management. They can assess your workers, schedules, systems, and practices, and provide advice on fatigue risk management.

Managing fatigue across the contracting chain

PCBUs in road and roadside work contracting chains should consider working together to create a fatigue management policy or agreement for all PCBUs in the contracting chain.

An agreement could include:

minimum hours of sleep opportunity between shifts and at least two full nights between each week of work
maximum shift length, considering:
- time of day
- type of work
maximum travel time before and after a shift
maximum hours to be worked in a week
maximum hours to be worked in a month
procedures for detecting, reporting, and addressing fatigue.

As well as the above, PCBUs should:

provide workers with training and information on fatigue management so they can self-manage outside of work hours
encourage open communication with workers to discuss mental health pressures. For more information, see Section 15.0: Mental wellbeing
make sure anyone can report fatigue-related issues to management
investigate incidents where fatigue may be involved.

Once these strategies are implemented, monitor and review them to make sure fatigue is managed effectively.

PCBUs should not create situations where there is pressure on PCBUs further down the contracting chain to meet requirements that are likely to result in fatigue or unhealthy work pressures for workers. For more information, see Section 3.0: Managing risk throughout the contracting chain

Worker responsibilities in managing fatigue

Workers must take reasonable care of their own health and safety, including managing fatigue. Workers should:

make sure they are well and ready for work at the beginning of their shift, having done everything possible to get a good sleep and rest. Their work schedule needs to make this possible – workers need enough time between shifts to allow for quality family and recreational time, as well as rest and recovery time
recognise the signs and symptoms of fatigue and communicate with their manager if they start showing these signs and symptoms
report fatigue-related incidents.

For more information, see Practical steps workers can take to manage fatigue

14.4 Impairment from drugs and alcohol

Medication, drugs, and alcohol use can result in impaired performance at work. This can make a worker a risk to themselves and others around them.

If workers are impaired, or may become impaired, by prescription medication, they should inform their site manager. Workers may perform work while taking prescription medication if a medical practitioner has cleared them to do so.

If a worker is impaired or suspected to be impaired by alcohol or illegal drugs, they should not be allowed to work.

Workers should be educated on the risks of working while impaired. These risks are especially high when working on or near vehicles and mobile plant, and when controlling traffic.

Drugs and alcohol policy

PCBUs should establish a drug and alcohol policy which includes strategies to deal with drugs and alcohol use or impairment during work hours. This should be done in consultation with workers and their representatives.

The drug and alcohol policy should contain at least:

the position on the consumption of alcohol on site
that workers must not be under the influence of illegal drugs
what action will be taken if a worker is suspected of being impaired.

If you decide to introduce drug or alcohol testing for workers, you will need to document when and how drug or alcohol tests may be performed. Examples of tests include:

pre-employment testing
post-incident testing
reasonable cause testing.

You should clearly identify safety-sensitive roles where drug testing may be applicable for managing risk.

For more information, see WorkSafe’s position on impairment and testing for drugs at work

Discuss your alcohol and drug policy during induction and training. Make sure all workers understand it. Regularly remind workers of the policy during team meetings.

You should support workers who want to seek help for drug and alcohol problems.

14.5 More information on fatigue and impairment

Fatigue
WorkSafe's position on Impairment and testing for drugs at work