Workplace health and safety when temperatures begin to rise

Maintaining a safe and comfortable working environment is essential for employee health, productivity, and overall wellbeing. One often overlooked aspect of workplace safety is temperature, be it too cold, or overly warm. A working environment that is too hot or too cold can pose significant health and safety risks, impacting not only the physical wellbeing of employees but also their mental health and productivity. 

While our UK summers can be unpredictable, it is good practice to prepare for the potential of warmer weather and even the extremes of heatwaves during the summer months. Below we look at the risks associated with an overly warm workplace, the symptoms of heat-related illnesses, and strategies to mitigate these risks.

The impact of heat in the workplace

While there's no law stipulating minimum or maximum working temperatures, guidance suggests a minimum workplace temperature of 16°C, or 13°C if employees are doing physical work. However, it is generally acknowledged that people work best when the workplace is between 16°C and 24°C (depending on the work environment and type of work). The Chartered Institute of Building Services Engineers recommends the following temperatures:

• 13°C for heavy work in factories

• 16°C for light work in factories

• 18°C in hospital wards and shops

• 20°C for offices and dining rooms. 

The reason for the variation in these recommended temperatures is the way that we deal with heat. The human body maintains a core temperature of around 37°C (98.6°F), and any significant deviation from this range can disrupt normal bodily functions. When exposed to excessive heat, the body attempts to cool itself through sweating and increased blood flow to the skin. However, prolonged exposure to high temperatures can overwhelm these mechanisms, leading to heat-related illnesses. This is compounded when someone is working strenuously, putting the body under even more stress. 

When the body absorbs more heat than it can dissipate, heat stress occurs, leading to a rise in core body temperature. Heat strain is the physiological response to heat stress, and can result in increased heart rate, sweating, and changes in blood circulation. If these responses are insufficient to cool the body, more severe conditions can develop. 

Health risks of an overly warm workplace

1. Heat exhaustion

Heat exhaustion is a common heat-related illness that can occur in warm working environments. It is characterised by symptoms including heavy sweating, weakness, dizziness, headache, nausea and muscle cramps. If not addressed promptly, heat exhaustion can progress to heatstroke, which is a life-threatening condition.

2. Heatstroke

Heatstroke is a severe medical emergency that occurs when the body's temperature regulation fails, and core temperature rises above 40°C (104°F). Symptoms include confusion, loss of consciousness, rapid heartbeat, and hot, dry skin (due to the cessation of sweating). Without immediate medical intervention, heatstroke can result in organ damage and death.

3. Dehydration

In warm environments, the body loses fluids through sweating in an attempt to cool down. If these fluids are not replenished, dehydration can occur. Symptoms of dehydration include dry mouth, thirst, dark urine, and fatigue. Severe dehydration can lead to kidney damage, seizures, and even death.

4. Muscle cramps

Muscle cramps are painful spasms that result from the loss of electrolytes and fluids through sweating. They often occur in the legs, arms, or abdomen and can be a sign of heat exhaustion. Adequate hydration and electrolyte replenishment are essential to prevent heat cramps.

5. Impaired coordination

An overly warm working environment can impair cognitive function and physical coordination, increasing the risk of accidents and injuries. Heat stress can lead to decreased concentration, slower reaction times and fatigue - all of which can compromise workplace safety.

6. Aggravation of pre-existing conditions

Employees with pre-existing health conditions, such as cardiovascular disease, respiratory disorders, or diabetes, are particularly vulnerable to the effects of excessive heat. Heat can exacerbate these conditions, leading to serious health complications.

The impact of heat on mental health and productivity

1. Reduced cognitive function

High temperatures can impair cognitive function, affecting concentration, memory, and decision-making abilities. This can lead to decreased productivity, as well as errors and accidents in the workplace.

2. Increased stress and irritability

Working in a hot environment can increase stress levels and irritability among employees. This can lead to conflicts, reduced job satisfaction, and a negative impact on mental health.

3. Sleep disturbance

Exposure to high temperatures, especially towards the end of the working day, can affect sleep patterns. Poor sleep quality can result in fatigue, reduced productivity, and a higher risk of accidents and errors.

Strategies to mitigate heat risks in the workplace

1. Temperature control

Maintaining a comfortable indoor temperature is the most effective way to prevent heat-related issues. Air conditioning, fans, and proper ventilation can help regulate temperature. Thermostats should be set to a range that balances comfort and energy efficiency.

2. Hydration stations

Providing easy access to drinking water is essential to prevent dehydration. Hydration stations should be placed in convenient locations, and employees should be encouraged to take regular drink breaks, especially during warmer weather.

3. Breaks and shaded areas

Encouraging employees to take regular breaks, especially in a cool, shaded area, can help reduce heat stress. Rest periods allow the body to cool down and recover from heat exposure. This is especially important when the workplace is outdoors, for example on a construction site, where it’s not possible to control the temperature.  

4. Suitable clothing and personal protective equipment (PPE)

Lightweight, breathable clothing can help reduce heat absorption, and should be provided where appropriate. In environments where personal protective equipment is required, choosing PPE designed for hot conditions, such as cooling vests, can help minimise heat strain.

5. Training and awareness

Educating employees about the risks of heat exposure and the importance of hydration and rest can help prevent heat-related illnesses. Training should include recognising the signs of heat stress and knowing how to respond in an emergency. NHS guidance recommends calling 111 if heat exhaustion is suspected, and 999 in the case of heatstroke.  

6. Monitoring and early intervention

Regular monitoring of workplace temperature and humidity levels can help identify heat risks. Employers should also monitor employees during warmer weather (or in especially warm workplaces) for signs of heat stress, and intervene early if symptoms are detected.

Conclusion

An overly warm working environment poses significant health and safety risks that can impact employee wellbeing, productivity, and workplace safety. Understanding these risks and implementing strategies to mitigate them is essential. By prioritising temperature control, hydration, rest, proper clothing and training, employers can create a safer, more comfortable working environment that supports the health and productivity of their employees.

Taking proactive measures to manage workplace temperature not only protects employees but also enhances overall workplace morale and efficiency. A comfortable and safe working environment is a fundamental component of a healthy, productive, and sustainable organisation.

Sources

Health and Safety Executive: Temperature in the workplace  https://www.hse.gov.uk/temperature/employer/managing.htm  

TUC: Heat – The case for a maximum temperature at work https://www.tuc.org.uk/sites/default/files/Temperature.pdf  

NHS: Heat exhaustion and heatstroke
https://www.nhs.uk/conditions/heat-exhaustion-heatstroke/