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Extreme heat threatens worker safety as warm weather becomes more frequent

Tom Austin-Morgan

 Heat is classed as a hazard and comes with legal obligations like any other hazard
Heat is classed as a hazard and comes with legal obligations like any other hazard

Temperatures reached a record-breaking 40°C in parts of England in July, with more hot weather following in August. The Health and Safety Executive (HSE) responded by saying that adapting to climate change is something all businesses must consider to ensure that extreme heat becomes part of their planning as warmer weather becomes more frequent.

The HSE said that employers have a legal obligation under the Management of Health and Safety at Work Regulations to assess risks to the health and safety of workers. They must review the risk controls they have in place and update them if needed. This includes risks from more frequent extreme weather.

John Rowe, HSE’s acting head of operational strategy, said: “We expect employers to take this recent weather event as the prompt to review how they assess the risk of high temperatures in their workplace and identify now those changes that will futureproof them.

“All workplaces need to acknowledge that the working environment is changing. There are low-cost adaptations to the structure of work, but things like improved ventilation and air conditioning should also be considered which will involve investment in the workplace.

“The extreme heat that we have witnessed of late isn’t going to stop and we want employers to plan and respond to this now.”

Temperature control

While there is no maximum temperature for workplaces, all workers are entitled to an environment where risks to their health and safety are properly controlled. Heat is classed as a hazard and comes with legal obligations like any other hazard.

The Workplace (Health, Safety and Welfare) Regulations require employers to provide a reasonable temperature in indoor workplaces – usually at least 16°C, or 13°C for strenuous work. However, what is reasonable varies and will depend upon the nature of the individual workplace. 

Employers must also manage the risk of working outdoors in heat by providing more frequent rest breaks in the shade, encouraging workers to wear long-sleeved shirts and wide-brimmed hats, or even scheduling work for cooler times of day.

There is no law for maximum working temperature because workplaces with hot processes such as foundries and certain manufacturing processes would not be able to comply with such a regulation, but all workers are entitled to an environment where risks to their health and safety are properly controlled. 

Those workplaces with hot processes use other measures to control the effects of temperature. These can include simple things such as providing free cool water and encouraging workers to drink often, providing periodic rest breaks and rest facilities in cooler conditions, issuing permits that specify how long workers should work in situations where there is a risk, or allowing workers to enter only when the temperature is below a set level or at cooler times of the day. 

Mechanical aids

More advanced measures could include controlling the temperature using engineering solutions, such as using fans or air conditioning, or physical barriers that reduce exposure to radiant heat. Alternatively, the process could be changed, or mechanical aids could be provided to reduce the work rate.

Rowe said: “All workers have a right to a safe working environment and their employers should discuss working arrangements with them.”

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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.


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