Thermal climate is a concept for the various factors that affect how people experience temperature. Air temperature, the temperature of surrounding surfaces, humidity and air speed affect what we experience.

Operative temperature describes how the body experiences the temperature in a room. Operative temperature is the average of the air temperature and the average radiant temperature from surrounding surfaces.

If the surfaces in a room are at the same temperature as the air temperature, the operative temperature is the same as the air temperature.

If some surfaces have a lower temperature than the air temperature, the operative temperature is lower than the air temperature. For example, near a cold window or an exterior wall.

The discomfort and problems from cold or heat depend not only on the air temperature, but also on a number of other factors. This can include, for example, clothing, physical activity, how long the work shift is and how often it is possible to take breaks in a more suitable temperature.

Even small differences are perceived as unpleasant. In an overall assessment, the climate in the individual case may therefore prove to be substandard even if the air temperature seems reasonable.

Perception of the climate is affected by

• radiant temperature from the temperature of surrounding surfaces, such as walls, floors, ceilings and windows
• air velocity, or in other words draughts
• humidity
• work intensity and clothing
• local or temporary factors such as uneven temperature and temperature difference between head and feet.

Air temperature and radiant temperature have the most effect on perception

Air temperature and radiant temperature are the climate factors that affect the perception of the climate the most.

Radiant temperature is the impact that surrounding warm or cold surfaces, such as windows and exterior walls, have on the climate. Such surfaces should have a temperature that causes the radiation to be perceived as symmetrical. This means that the difference in temperature between different surfaces, such as between underfloor heating and an uninsulated window, should be as small as possible.

Radiant temperature affects the climate as much as air temperature. In a well-insulated building, the radiant temperature is often equal to the air temperature.

As an employer, you are responsible for reducing the risks that the thermal climate in the workplace can involve, just as you are responsible for all aspects of the work environment. You must be familiar with the Work Environment Act and other work environment regulations.

The employer has the main responsibility for ensuring that the thermal climate in the workplace meets the regulations, but property owners, developers and designers also have a responsibility for the thermal climate in the workplace.

Controlling and correcting the thermal climate is part of ongoing safety work in the workplace. The employer must schedule measures that cannot be implemented immediately, for example in the annual action plan. Heating and cooling installations must be maintained so that they retain their function.

As an employer, you have the same responsibility for the work environment, regardless of whether you rent or own the premises. However, you can in turn make demands on the landlord. If heating is included in the landlord's commitment, you can normally request that the temperature complies with applicable regulations.

When you rent premises where employees will work, it is your responsibility as an employer to check that the premises can meet climate requirements, for example in summer heat.

For work outdoors, you as an employer are responsible for designing the workplace so that employees are protected from the elements as much as possible. Sometimes work must be interrupted in cold weather, because extreme cold, or cold combined with wind, can be dangerous. The interruption is then done with the support of specific practices in certain industries, or, for example, agreements in contracts.

The property owner also has a responsibility for the thermal climate. The Swedish Work Environment Authority can prohibit a property from being rented to a certain business if it does not have the ability to provide a good work environment.

Clients and designers have a special responsibility to ensure that the building can comply with work environment regulations during the design process.