Indoor air - Yleistä


General information on topic

Poor indoor air quality is known to cause, for example,

  • respiratory tract Infections
  • nasal congestion or discharge
  • itching, burning or irritation of the eyes
  • throat hoarseness or dryness
  • general fatigue and headaches, and
  • on rare occasions, fever and muscle and joint pain.
Chronically poor indoor air quality is a health hazard.

If there is an indoor climate issue, symptoms typically occur inside the building. Usually the symptoms ease once the affected person has left the building.  

If workers are found to be suffering from an indoor climate issue at the workplace, the employer must take any necessary steps to prevent exposure and eliminate the causes.

Many factors can cause an indoor climate issue

The following factors can contribute to poor indoor air quality (the list is not exhaustive):

  • ineffective or insufficient ventilation (correct capacity for the number of persons)
  • release of mould spores from damp structures
  • flooring materials’ reactions to moisture
  • volatile unhealthy emissions from construction and interior decoration materials and furniture
  • mineral wool fibres released from uncoated ventilation duct dampers and soundproofing boards
  • temperature conditions and draughtiness that have negative impact on well-being
  • items that do not belong to the workspaces
  • incorrect cleaning methods or inadequate cleaning.

Indoor air quality issues must be tackled methodically

There must be agreed procedures in place to tackle indoor climate issues, and based on these procedures the employer

  • informs personnel about poor indoor climate at the workplace 
  • setting up a working group on indoor air quality, if necessary
  • consulting occupational health care professionals
  • uses experts on indoor climate to review the condition of the building and to assess the results
  • disseminating information openly and promptly
  • drawing up a plan and a schedule of corrective actions and implementing the same
  • monitoring the impact of the actions taken on workers’ health
  • supports proactively the work community’s and employees’ work capacity together with the occupational health care.

Indoor air - Työntekijälle


Instructions for employee

Let your employer and occupational safety and health representative know if you suspect that there is a problem related to indoor climate at your workplace. Your employer has a duty to keep both you and the occupational safety and health representative up to date on any actions that have been or will be taken to address the issue. Your employer must also let you know if they deem it unnecessary to take any action.

You should let your employer and occupational safety and health representative know if you notice any symptoms that you believe could be due to poor indoor air quality at your workplace. The employer must determine together with occupational healthcare whether your symptoms are caused by the conditions at the workplace. You should also talk to your employer’s occupational health care provider about any symptoms. Occupational health care professionals can propose changes to allow you to continue working in the space that is causing you symptoms.

If your symptoms are found to be caused by poor indoor air quality at your workplace, your employer must take steps to find out the cause of the issue and eliminate it. Your employer is also responsible for ensuring that your health is not put at risk while the investigation is carried out and the remedial action implemented.

It takes time to carry out a thorough investigation, draw up a report and a plan of corrective actions, and to implement the plan. You can ask your line manager or occupational safety and health representative for updates on the situation and when solutions are expected.

The occupational safety and health authority supervises

If your employer does not take appropriate measures to examine the cause for poor indoor air quality and to prevent exposure, you can call the occupational safety and health authority’s national helpline for advice and information.

Indoor air - Työnantajalle


Instructions for employer

Health risks caused by indoor climate must be prevented

Good planning and construction prevent indoor climate issues. This means, for example, that emission-free building and interior decoration materials are selected and that proper and functional ventilation is provided. Additional attention should be paid to
-    efficient engineering solutions, such as drainage
-    functional and clean ventilation system
-    regular maintenance of the building
-    cleaning. 

Any leaks must be addressed immediately and the affected structures dried in order to prevent microbial growth. As a rule, any damaged materials should be removed. The cause must be investigated and repairs carried out to prevent any recurrence of the problem.

In the event that the building is leased, the employer must contact the landlord to agree on repairs and maintenance. The employer is always ultimately responsible for their workers’ health. The employer can terminate the lease agreement if the conditions in the building are obviously putting workers’ health at risk.

The employer must ensure that the workplace is healthy and safe to work in.

Health hazards must be eliminated without delay and the impacts of the remedial action monitored

It is the employer’s duty to ensure that there are procedures in place to prevent any harmful effects on health resulting from poor indoor climate and to address any issues.

Procedure for addressing indoor air quality issues in the workplace

Graph: Addressing indoor air quality issues in the workplace

It is the employer’s duty to

  • consult with their occupational health care provider or other health care specialists to establish whether any symptoms of workers are due to their work
  • determine in cooperation with their occupational health care provider which workers could potentially continue to
  • determine the condition of the building reliably and thoroughly and assess its impact on the indoor climate (indoor climate review); if the employer does not have required expertise, an expert should be used for the indoor climate review
  • carefully plan for repairs and implement them so that the repair work does not negatively affect the construction workers or others in the vicinity
  • work in the affected building without risking their health and on which conditions
  • carry out the repairs as planned
  • ensure that the facilities are properly and sufficiently cleaned after the repairs
  • monitor in close cooperation with their occupational healthcare provider or other healthcare professionals the adequacy of any action taken and its effect on employees’ health.

Employers can prevent rumours by communicating openly about any investigations into indoor climate issues and the progress of remedial action. If there is insufficient communication about investigating the indoor climate issue, the employees might get an impression that the employer does not take employees’ symptoms seriously.

Setting up a working group on indoor air quality is often a good idea. In most cases, these kinds of working groups consist of line managers, representatives of the property owner and the maintenance company, the employer’s occupational safety and health manager and the occupational safety and health representative, occupational health care professionals and a representative of the affected workers. External specialists can also be invited to the working group’s meetings.

Open and timely communication is crucial

Employers can prevent rumours by communicating openly about any investigations into indoor climate issues and the progress of remedial action. If information about how indoor air quality issues are being dealt with is withheld, workers may think that their employer is not taking their symptoms seriously even if the employer has in fact taken steps to address the issue.

When investigating an indoor climate issue at the workplace, it is important to remember that details about individual employees’ health constitute classified information legislation enforced by the health protection authority on indoor climate issues. Information about individual workers’ health cannot be shared with other workers. Only health care professionals can determine whether workers’ symptoms are caused by something in their workplace.

In order to keep workers properly informed about the progress of steps taken to address indoor climate issues, employers should give them regular updates on

  • what is known
  • what is not known
  • what will be done to remedy the situation
  • when will remedial action be taken
  • what will happen next, and
  • how the impact of remedial action will be monitored.

Indoor air - Lainsäädäntö



Occupational Safety and Health Act (738/2002)

  • Section 8 – Employer’s general duty to exercise care
  • Section 10 – Analysis and assessment of the risks at work
  • Section 32 – Structural and functional safety and health of the workplace
  • Section 33 – Ventilation of workplaces and volume of workrooms
  • Section 40 – Biological agents

Occupational Health Care Act (1383/2001)

  • Section 5 – Occupational health care professionals and experts
  • Section 12 – Content of occupational health care

Government Decree on Safety and Health Requirements in Workplaces (577/2003, in Finnish)

  • Section 2 – Employers’ general obligations
  • Section 9 – Capacity and ventilation of workspaces

Act on Commercial Leases (482/1995, in Finnish)

  • Section 50 – Tenant’s right to terminate the lease

Indoor air - Oikeuden päätökset


Court decisions and precedents

The Supreme Court of Finland found in a case in 1998 (KKO:1998:22, text in Finnish) that a teacher had contracted occupational allergic rhinitis and conjunctivitis after working in a school between 1980 and 1993 that was later revealed to have high levels of mould and airborne mould spores as a result of leaks, structural damp and inadequate air conditioning. The Court concluded that the teacher’s health issues were occupational diseases that had been caused by long-term exposure to high levels of mould in the school building and that the teacher was consequently entitled to compensation.

Indoor air - Muualla Tyosuojelu.fissä

Indoor air - Sanasto


Indoor air quality issue A health hazard resulting from poor indoor air quality in a building or a part of a building. Examples of causes include structural defects, inadequate maintenance, damp and mould resulting from leaks, and chemical reactions of building materials. Poor indoor air quality can also be due to organic dust, articles inside the building or emissions from processes.
Working group on indoor air quality A working group composed of specialists of different fields and representatives of the occupiers of the affected building, tasked with planning and coordinating the process by which indoor air quality issues are addressed and analysing the findings of investigations and recommended actions. The working group is also responsible for planning and coordinating how information about the process is communicated to different parties. Many local authorities and large organisations also have a coordination committee for indoor air quality to draw up investigation and communication policies, run training courses and monitor the progress of remedial action.
Exposure In the context of occupational safety and health, ‘exposure’ refers to workers being exposed to unwanted or harmful agents at work. Exposure agents can be chemical, biological (e.g. micro-organisms or cells) or physical (e.g. vibration, radiation, thermal conditions or electrical currents). Exposure can occur internally or externally. Internal exposure refers to exposure agents being absorbed through the skin or entering the body through broken skin or the eyes, inhalation or ingestion and affecting the body from the inside. External exposure refers to exposure agents affecting the body from the outside (e.g. radiation).
User survey User surveys are designed to identify the causes of poor indoor air quality or structural damp in order to focus remedial action in the right areas of the building. They include questions about users’ observations of damp or mould in the building and the underlying reasons. Users are also asked about their experiences of indoor air quality in the building, including their views on temperature, draughts, odours and other potential nuisances. The surveys are not used to collect information about workers’ symptoms. In respect of symptoms, the only objective is to determine whether any symptoms that workers may be experiencing could be linked to spending time in the building. User surveys are anonymous in order to protect respondents’ privacy. However, each respondent is first asked to identify the room or workstation where they primarily work in order to pinpoint the locations of any problems that are identified.
Indoor air quality survey Indoor air quality surveys are used to collect more detailed information about indoor air quality in connection with various kinds of research projects or if an indoor air quality issue has been identified as well as to find out more about workers’ symptoms. These kinds of surveys can also be used to study the effectiveness of any remedial action taken. The most common type of indoor air quality survey in Finland is the MM-40 questionnaire, which was developed at Örebro University Hospital in Sweden. It is important to survey everyone who can potentially be affected by the issue. Interpreting the answers requires specialist expertise. As the respondents are asked to provide details about their health, the answers are confidential. Any symptoms reported by respondents are analysed on a general level and not as specific diseases.
Engineering survey A systematic investigation of the structure of a building to identify any high-risk engineering solutions and the location and extent of any structural damage and to determine their impact on indoor air quality. In most cases, the survey consists of an assessment of the health of the building and a structural survey. The causes of any structural damage are also studied and the need to dismantle damaged structures and replace materials assessed. The objective is to come up with recommendations as to how the damage can be repaired and the causes eliminated. The findings are used as a basis for planning repairs.