Heat Stress and Fatigue Management: How to Manage Worker Fatigue in High-Temperature Environments

The Connection Between Heat Stress and Fatigue

Working in hot conditions stresses your body’s cooling system, which can result in heat-related conditions and illnesses, highlighting the importance of effective heat stress and fatigue management. Heat stress can produce acute and chronic health effects, and when these effects are experienced at work, worker safety is compromised.

The connection between heat stress and fatigue is strong, as heat stress can result in an illness called heat exhaustion. Heat exhaustion results from continuous exertion in heat, accompanied by dehydration from deficient water and salt intake. This illness manifests in a variety of symptoms, including fatigue. Fatigue is characterized by feeling extremely tired or weak. Once fatigue sets in, workers may become more susceptible to other heat-related illnesses. Fatigue raises workers’ risk of heat-related illnesses, creating a dangerous cycle.  Implementing effective heat stress and fatigue management practices is crucial to prevent these issues and keep workers safe.

Causes of Heat Stress and Fatigue in the Workplace

Heat stress and fatigue management need to be prioritized in all workplaces with temperature extremes. The human body normally regulates its internal temperature, but under conditions with high ambient air temperature, little air movement, and humidity, this control mechanism can be overstrained.

Beyond environmental factors, workers can experience heat stress due to job factors, such as personal protective equipment (PPE). For example, construction workers must wear full-body PPE, such as hard hats, gloves, coveralls, and sometimes respirators. Wearing all this clothing while performing physically demanding tasks like manual labour, climbing, or working at heights can exacerbate heat stress risk, highlighting the need for effective heat stress and fatigue management strategies in these situations.

Additionally, many personal risk factors can cause heat stress, such as:

• Previous heat illnesses: Workers are more sensitive to heat if they have experienced a previous heat-related illness.
• Age: As the body ages, its sweat glands become less efficient. Workers over the age of 40 may therefore have trouble with hot environments.
• Alcohol consumption: Alcohol consumption during the previous 24 hours leads to dehydration and increased risk of heat stress.​
• Medication: Certain drugs may cause heat intolerance by reducing sweating or increasing urination.

The Effects of Heat Stress and Fatigue on Workers

The effects of heat stress emphasize the importance of heat stress and fatigue management. Heat stress can cause fatigue, dizziness, headaches, nausea, and decreased cognitive function. As workers experience the physical effects of heat stress, their reaction times slow, judgment becomes impaired, and the risk to their safety and the safety of their colleagues is at a heightened risk.

Once the initial symptoms of heat stress appear, time is of the essence for the impacted individual to make a full recovery. Our experts want to emphasize the importance of knowing the signs and symptoms of heat stress, as it can be fatal.

We asked Louise Caicco Tett, President of HSPI, to weigh in on the dangers of heat stress. “I’ve had workers tell me about themselves and coworkers feeling nauseous while working outdoors in hot environments. They don’t realize they’ve suffered from heat stress, which can be very serious. Workers need to bring these situations forward to their supervisors and request that protocols be put in place to require regular hydration breaks, shaded rest periods, and symptom reporting to keep everyone safe. This is a great topic for joint health and safety committee members to address as we move into summer. Make it part of monthly inspections,” Louise says.

Strategies for Managing Heat Stress and Fatigue

Now that we have discussed the connection between heat stress and fatigue, and its causes, we will examine strategies for heat stress and fatigue management. Our experts have identified five strategies, which we outline below:

• Install mechanical ventilation (high-volume fans or localized air-conditioning) to regulate ambient temperatures and remove excess heat from indoor work areas.
• Adjust work schedules and demands to avoid having employees work during the hottest times of the day.
• Provide regular breaks and hydration to reduce the exposure to heat stress hazards.
• Implement cooling measures, such as fans and cooling tents.
• Promote a buddy system, where workers encourage each other to stay hydrated and take regular breaks, out of the heat.
• Monitor workers’ health and well-being by conducting regular check-ins for signs of heat stress.

Best Practices for Heat Stress and Fatigue Management

Effective heat stress and fatigue management requires a preventive approach. We recommend the following best practices:

• Conduct regular risk assessments to identify potential heat stress hazards and implement controls.
• Provide comprehensive training to workers on recognizing symptoms, prevention strategies, and emergency response procedures.
• Develop and regularly practice emergency response plans, ensuring workers know what to do in case of a heat-related emergency.

Heat stress and fatigue have detrimental impacts on employee health and well-being. By following the strategies and best practices discussed, employers can better manage heat stress and fatigue. If you are unsure about the risk of heat stress in your workplace, HSPI’s Workplace Hazard Assessment services have got you covered. Collaborating closely with employers, we tailor a suitable solution for your workplace. To learn more about our Workplace Hazard Assessment services, please visit our website.