Is there a maximum working temperature

With the temperature forecasted to reach 40°C, breaking the current record for the hottest day ever recorded in the UK, being 38.7°C, you might be asking yourself:

“Is there a maximum working temperature?”

The short answer for this is ‘no’, there is no law for maximum working temperature or law to state when it’s too hot to work.

However, the temperatures in workplaces, like offices or similar environments, must be kept reasonable as employers must stick to the health and safety at work law. This includes:

  • Keeping the temperature at a comfortable level, sometimes known as thermal comfort
  • And providing the flow of clean and fresh air

What is thermal comfort?

Thermal comfort is extremely difficult to describe because while determining what constitutes a suitable working temperature, you must take into account a variety of environmental, work-related, and personal aspects.

The best you can realistically expect to achieve is a thermal environment that is comfortable for the majority of workers within a workplace. To measure thermal comfort, the number of workers reporting thermal discomfort, not the temperature of the room, is used. The six basic factors better explain why room temperature alone is not a reliable predictor of thermal comfort.

What are the six basic factors of thermal comfort?

The six factors that influence thermal comfort are both environmental and personal, and while they may be independent, they all contribute to an employee's thermal comfort.

The environmental factors are:

  • Air temperature
    • This is the temperature of the surrounding air and is typically expressed in degrees Celsius (°C).
  • Radiant temperature
    • Thermal radiation is the heat emitted by a warm object. Radiant heat may be present in an environment where there are heat sources.
  • Air velocity
    • This describes the rate at which air moves across the employee and may aid in cooling them if the air is cooler than the surrounding environment.
  • Humidity
    • When water is heated and evaporates into the surrounding environment, the amount of water in the air that results provides humidity.

The personal factors are:

  • Clothing Insulation
    • Thermal comfort is heavily dependent on the insulating effect of clothing on the wearer, as it can be both a potential cause and control for it.
  • Metabolic heat
    • We generate more heat as we do more physical work. The more heat we generate; the more heat must be lost to avoid overheating. The importance of metabolic rate on thermal comfort cannot be overstated.

Ways to stay safe during the heatwave:

The most important thing to do during this heatwave is to stay hydrated by drinking plenty of water while avoiding any sugary, caffeinated, and alcoholic drinks and be sure you do not spend too much time in direct sunlight. You should also ensure that your working environment is adapted to combat the heat and to ensure your thermal comfort, for example improving air velocity with fans or reducing clothing insulation as much as possible.

If you have any questions about this topic, Contact Us by phone: 01922 474 999 or by email: This email address is being protected from spambots. You need JavaScript enabled to view it., and we will answer them.