Sleepiness is a psychological state of feeling tired that can not only make time on the job seem longer and more challenging, but also reduce a worker’s ability to function safely.

By Sarah Ripplinger

Fatigue puts workers at a greater risk of sustaining injuries from hazards at work. WorkSafeBC’s information sheet Managing the risk of fatigue in the workplace provides guidance for employers and workers.

“This resource represents a shift in thinking about fatigue in the workplace,” says Jenny Colman, an ergonomist with WorkSafeBC. “While we once saw fatigue as the hazard, we now think of it in terms of a contributory factor that can increase the risk of harm or potential for harm from work being performed. Therefore, higher protections need to be in place around the tasks performed by a worker who is tired.”

How fatigue affects a task

Fatigue can make it difficult to concentrate, especially when it comes to tasks that require quick reactions, alertness, and vigilance. Recalling information and making decisions may be impeded, particularly when time is of the essence and complex information processing and comprehension is involved.

Some work schedules put workers at greater risk

Everyone can experience fatigue for various reasons, particularly when they do not get enough restful sleep. However, shift work and working overtime tend to put workers at greater risk, particularly when a shift extends to 12 hours or more and when work takes place during the night — when the urge to sleep is greatest.

Research found that being awake for 17 hours in a row can have effects similar to a blood alcohol level of 0.05, the level at which it is illegal to operate a motor vehicle in B.C. The longer someone is awake beyond 17 hours, the greater the effect of impairment. Irregular shift rotations can also amplify these effects.

The workplace environment can also contribute to fatigue. To reduce its onset, provide adequate lighting and limit workers’ exposure to excess noise, heat, cold, or vibration such as from operating machinery.

Work tasks and type of work can be fatigue-inducing. For example, workers who engage in repetitive or strenuous tasks, or whose work is physically or mentally demanding, are more likely to feel tired.

A risk assessment informs effective controls

Given that fatigue is a common occurrence, employers should conduct a risk assessment by reviewing work activities and systems to assess for the risk of worker injury or adverse outcomes if a task is performed by a fatigued worker, says Colman. “The employer will need to implement control measures, then monitor them to ensure their ongoing effectiveness.”

Three important steps to take:

1. Identify workplace activities where being fatigued could increase the risk of harm. Examples include making complex decisions, working at heights, performing calculations, and operating tools or machinery.
2. Determine how each workplace activity could increase the risk of harm if and when a worker is fatigued, and who may be affected. For instance, if a driver is tired, what could happen, and could other workers in the vehicle or members of the public be affected?
3. Eliminate the hazard if possible, or redesign workplace activities to reduce the risk of harm. Follow the hierarchy of controls to ensure that levels of protection are adequate and effective when fatigue is present.

Find out more

For more information, see the following:

• Managing the risk of fatigue in the workplace (information sheet)
• Fatigue impairment (webpage)
• Controlling risks (webpage)

This information originally appeared in the Spring 2024 issue of WorkSafe Magazine. To read more or to subscribe, visit WorkSafe Magazine.