Minimum Working Temperature – What the Law Says!

mimumum working temperature


Under the Workplace (Health, Safety and Welfare) Regulations 1992, employers are required to keep the temperature in the workplace to a ‘reasonable’ level.

In practice, what would be classed as ‘reasonable’?

Minimum working temperature

There is no set minimum working temperature, however, the Workplace regulations suggest that the general minimum working temperature should be 16 degrees Celsius, and in a situation which involves regular and active physical effort, the working temperature should be kept to a minimum of 13 degrees Celsius.

These temperatures are not legal requirements and it is the responsibility of the employer to assess their workplace to decide what minimum working temperature is suitable.

Is there a maximum working temperature?

There is no legal maximum working temperature. Again, the employer must arrive at a reasonable upper working temperature by assessing their workplace.

Risk assessment

Both the Workplace Regulations and the Management of Health and Safety at Work Regulations 1999 place a responsibility on the employer to carry out a risk assessment of their workplace to ensure the health and safety of their workers, visitors and the general public.

One important aspect of any employer’s risk assessment must be to check that the temperature in the workplace is maintained at a reasonable level for their employees.

When carrying out a temperature risk assessment, there are certain factors that should be considered:

  • thermal comfort
  • heat stress
  • cold stress
  • extreme temperatures
  • personal protective equipment (PPE)

Thermal comfort

Thermal comfort is the feeling of comfort a person derives from not being too hot or too cold. Factors that could affect thermal comfort include clothing worn (personal clothes, uniform or protective clothing), humidity, sources of heat or cold, and how physically demanding a work role is. As such, thermal comfort can vary greatly between individual members of a workforce.

Thermal comfort is demonstrated by the number of staff who are happy with the working temperature, rather than a specific temperature setting. It is therefore the employer’s responsibility to ensure that the workplace temperature is maintained at a level that suits the majority of their employees.

Achieving thermal comfort for the majority of a workforce can improve the productivity of staff, raise their morale and add to their general health and safety.

Whereas an employee who is too hot at work, for instance, is likely to perform work tasks less efficiently, may be reluctant to wear protective clothing, and will probably take more breaks to escape the heat.

When carrying out a risk assessment for thermal comfort, consider:

  • air temperature (i.e. the general temperature in a workplace)
  • any factors or objects that create heat, for instance, an oven or kiln, machinery or even the sun
  • air velocity and ventilation, for instance, drafts that may cause employees to feel cold
  • clothing – are employees dressed suitably for their work environment? Does a work uniform or protective clothing cause discomfort?
  • physical effort – for instance, where a role is physically taxing and results in a member of staff producing excess body heat, does that employee require extra rest periods?
  • Individual factors, such as weight, age or fitness level

One of the best ways to assess thermal comfort is to speak to employees. Do they feel generally comfortable with the temperature in their workplace? Gathering their individual opinions may well flag up a trend that you had not considered.

Heat stress

Where a person’s body cannot control its temperature in a hot environment, this leads to heat stress. They overheat.

Heat stress could arise from any of the following situations:

  • carrying out strenuous work for a long period outdoors on a hot sunny day
  • working in a bakery where there are ovens nearby
  • working with molten metals
  • working in a boiler room
  • working in a laundry

Where an employee consistently experiences heat stress, they may find it difficult to concentrate, develop heat rashes, be constantly thirsty (and therefore take more breaks to have a drink), faint, suffer from heat exhaustion, and in severe cases, experience heat stroke.

Cold stress

By comparison, cold stress happens when a person’s body temperature becomes too low. This could be as a result of working outside in cold weather without suitable clothing, working near or in a cold storage area, or working in a draughty environment.

Factors resulting in cold stress include working in cold temperatures, working in high or cold wind, working in a damp environment, and working with cold liquid.

Cold stress may lead to poor circulation, frostbite, shivering (which may result in muscle cramps) and in serious cases, hypothermia.

Extreme temperatures

Where employees are regularly working in very hot or very cold environments, once the risk assessment has been carried out and any resulting changes implemented, it will be necessary to monitor the work environment much more closely and regularly than a workplace where the temperature is moderate and easily maintained at a reasonable level.
Depending on the work, environment and staff members, it may also be necessary to carry out regular health screening for the employees involved.

Personal protective equipment (PPE)

Personal protective equipment includes clothing items such as high visibility jackets, gloves and overalls. Such PPE items may cause overheating when worn in an already warm environment. Where the items are bulky, they may also cause additional physical effort, leading to sweating and additional body heat.

What routines or guidelines can be put in place to reduce the risk of overheating, for instance, regular breaks from wearing PPE?

Managing working temperatures

Once an employer has assessed their workplace temperature, there are a number of ways that they can work towards thermal comfort:

  • providing controllable and safe heating equipment, such as radiators
  • providing cooling equipment, such as fans and air conditioning
  • ensuring that windows can be opened safely and sufficiently for ventilation and cooling
  • providing thermal and/or protective clothing, where required
  • providing rest facilities where workers are involved in hot work (e.g. working with a furnace) or in a low temperature environment (e.g. cold stores)
  • ensuring workrooms have sufficient space for ventilation purposes and to ensure that personal overheating does not occur due to overcrowding
  • fitting blinds or reflective film on windows to provide shade and limit heating from direct sunlight
  • ensuring workstations are not located in direct sunlight
  • ensuring workstations are not placed close to machinery or equipment that gives off heat
  • providing appropriate facilities so that employees have access to cold or hot drinks
  • insulating pipes that may generate heat
  • introducing working patterns that limit exposure to risk, for instance, flexible working or job rotation
  • altering processes in the workplace to minimise risk, for instance, where a process, or part of a process, can be contained in a closed area or automated
  • reducing draughts
  • where appropriate, changing floor coverings, for instance, from a stone floor that causes workers’ feet to become cold to a carpeted floor
  • where working outdoors or off-site, providing mobile facilities, for instance, for heating or to have hot or cold drinks
  • where working in extreme temperatures, providing regular rest breaks to escape the heat or cold
  • where working outside, rescheduling work in very cold or very hot weather
  • where working outside, providing shade from direct sunlight

The issue of working temperature and thermal comfort should be treated as another factor in any employer’s health and safety regime to ensure the welfare of their workforce.


Minimum Working Temperature – What the Law Says! 1

Gill Laing is a qualified Legal Researcher & Analyst with niche specialisms in Law, Tax, Human Resources, Immigration & Employment Law.

Gill is a Multiple Business Owner and the Managing Director of Prof Services - a Marketing Agency for the Professional Services Sector.

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