Ventilation and air quality

The air in the workplace affects the employees. Air pollutants such as hazardous substances, odours, moisture, particles and dust must be removed. This requires good ventilation. General ventilation ventilates the entire premises. Process ventilation removes contamination at the source.

Ventilation and air exchange

Ventilation means exchanging the air. This means that polluted air in a room is replaced with fresh air from the outdoors, so-called outdoor air. A ventilation system controls how air is supplied and distributed in a room. Good ventilation reduces the level of pollutants in the air, but it cannot remove all pollutants.

General ventilation ventilates the entire premises

The indoor air in a workplace can contain many different pollutants, such as hazardous substances, odours, moisture, particles, dust, allergens of various kinds, viruses and bacteria. Air pollution affects employees' respiratory tracts, eyes, skin and internal organs.

  • In offices, schools and similar premises, it is primarily the people themselves, building materials and furnishings that emit pollutants. This means that the entire premises need to be ventilated using general ventilation.

    To achieve good general ventilation, a certain amount of air exchange is needed, i.e. the amount of outdoor air supplied to the premises. It is also important that the air supplied to a room, the supply air, is clean. The supply air must be supplied to the parts of the premises where the employees are present, without causing any unpleasant draughts.

General ventilation and air quality

Process ventilation removes hazardous substances from products and processes

Many workplaces emit substances that are directly hazardous to health. This applies to construction activities and workshops, but also to hairdressers and nail sculptors, for example.

What is emitted is dust and fumes, as well as vapours from liquids and gases that are harmful to health. If the hazardous substances are not removed, they can cause serious illnesses, either immediately or after prolonged inhalation. They can even be fatal.

  • If the pollutants are emitted in a concentrated area, the ventilation should take care of the pollutants as close to the source as possible. This is called process ventilation. One example of process ventilation is local exhaust ventilation during welding.

    Even if there is process ventilation, general ventilation is needed in the work area. General ventilation should take care of the pollutants that process ventilation has not managed to capture, as well as the pollutants that are emitted throughout the premises.

  • Minimise pollution primarily by using materials, machines, processes and working methods that emit as little air pollution as possible. It is also possible to limit the spread of air pollutants by encapsulating processes or carrying out work that generates a lot of air pollutants in separate spaces. If this is not sufficient, process ventilation should be installed.

Process ventilation captures pollutants close to the source

Health problems can be caused by the building

So-called building-related ill health can be linked to the building in which the workplace is located. For example, the building may have damp damage and mould, which in turn may be caused by, for example, water leakage, condensation of damp air or building moisture from when the building was constructed.

Emissions from materials and poor cleaning also have an impact. Poor ventilation can exacerbate these problems, as it can lead to high levels of pollutants in indoor air.

Always investigate building-related ill health

The cause of the building-related ill health must be investigated. Moisture damage, dampness and mould, whether ongoing or old, should be addressed at the source, not by increasing ventilation.

Get a better work environment through working systematically

As an employer, you must manage the work environment systematically, so as to improve it. Our provisions for systematic work environment management apply to all employers – regardless of the activities or the risks that you and your employees could be exposed to.

The employer is responsible for the risks of poor air quality

As an employer, you are responsible for reducing risk from poor air quality and inadequate ventilation, 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.

Employees and safety representatives are important for a good work environment

Employees and safety representatives have an important role in work environment management. As an employer, you must give all employees the opportunity to participate in work environment management. For example, you can let employees suggest measures or provide feedback on measures you have implemented.

Employees' participation in work environment management

As an employee, you must participate in work environment management and participate in implementing the measures needed to achieve a good work environment. You must follow the employer's instructions. You must also report to your employer or your safety representative if the work involves immediate and serious danger to life or health.

Last updated 2025-11-26