The Workplace Ordinance describes that in enclosed workspaces "breathing air that is beneficial to health must be available in sufficient quantity". As a rule, this corresponds to the quality of the air outside. The nitrogen dioxide limit value in offices is 40 micrograms per cubic metre on an annual average. This value is based on the EU Air Quality Directive and the World Health Organisation (WHO) and has been incorporated into the Immission Control Act. The aim of the limit value is to protect infants, children, sick people, pregnant women or old people. The workplace regulations set a comparable value for the indoor climate in normal offices - to protect workers.
Confusion is sometimes caused by the fact that there is still a limit value from the 1990s, which is 60 micrograms per cubic metre of air and refers to the weekly mean value for indoor rooms. However, this value is only considered a guideline value, which was originally defined by an indoor air hygiene commission long before the EU directive. In an interview with ARD-Faktenfinder, however, the Federal Environment Agency recommends that this value no longer be applied due to current scientific findings. An adjustment is imminent in the coming years.
The limit values for carbon dioxide in offices and at the workplace can be found on the measured values page.
Less performance due to poor air quality
Healthy indoor air and a good indoor climate have a decisive influence on the well-being of office employees and their ability to concentrate and perform. The brain needs sufficient oxygen to be able to work at the highest level of performance. The decisive factor for permanently healthy air in the office is not so much the decreasing oxygen content in stale air, but above all the carbon dioxide content of the air we breathe: fresh air consists of 21 percent oxygen and contains about 0.04 percent CO2 (400 ppm). When we exhale, we return air to the office that has an oxygen content of 16 per cent but contains four per cent carbon dioxide (40,000 ppm).
So while the oxygen content of the air in the open-plan office slowly decreases and only falls below the critical mark of 18 percent after hours, the highly concentrated breathing air very quickly increases the carbon dioxide content. Everyone knows it: an hour of concentrated work in a closed conference room often leads to headaches and difficulty concentrating - this already happens with carbon dioxide levels between one and 2.5 percent. (1,000 to 2,500 ppm).
The official occupational exposure limit is 5,000 ppm - the Federal Environment Agency working group rates concentrations of less than 1,000 ppm as harmless. Values between 1,000 and 2,000 are classified as "noticeable", concentrations of more than 2,000 ppm are considered unacceptable.
Health consequences of thick indoor air
It has been proven that thick or bad air has an influence on our health. When the CO2 content in the blood rises, the blood vessels dilate to receive as much oxygen as possible. If this happens, blood pressure drops, leading to listlessness or fatigue. The problems range from mild discomfort to chronic damage:
- Well-being: Poor air quality in the office significantly reduces human well-being. This manifests itself as fatigue or irritability or in fluctuating moods. If this continues, sudden headaches or nausea can be the result. This effect is often described as "sick building syndrome".
- Mucous membranes: Continuous inhalation of foul air can lead to irritation of the mucous membranes and even laryngitis.
- Eyes: In addition to the respiratory tract, the eyes are also susceptible - conjunctivitis can also be a result of poor indoor air.
- Allergies: In bad air, we come into contact with allergens such as dust mites, mould spores, hair or dander. This contact can lead to rhinitis, allergic asthma or even skin eczema.
- Back and neck pain: In office environments, draughts or cold air currents often lead to pain in the back or neck area.
Many of the symptoms mentioned are exacerbated by sitting for hours on end and thus a lack of exercise.
How do you ensure performance?
The basic recommendation for avoiding thick air in the office is to check the air quality - and then react if, for example, the carbon dioxide content exceeds the critical limit of 1,000 ppm. The air-Q air analyser can be ideally used for this purpose.
When ventilating, make sure that the window or windows are not tilted, but fully opened. Tilting the windows creates draughts. Basically, it is recommended to ventilate for a maximum of five minutes every two hours. Ventilating against bad air to ensure performance also has disadvantages, however: For example, if the window faces a busy road, ozone, particulates or pollen may enter the office from outside.
To rule out ineffective ventilation, the air-Q again helps: by recording the development of the air quality in real time, it is possible to precisely track which values have improved or deteriorated as a result of ventilation. Therefore, it is important to find out the right time for prolonged ventilation.
Ventilation is of course also possible through open doors: if there is no busy street or large car park in front of the house, ventilation through open doors can be more effective than ventilation through windows. This is because the exchange of air below the windows is more reliable.
More tips for a better indoor climate:
- Place printers or copiers in separate rooms
- Damp mopping the floor daily
- Use plants to create a biophilic indoor climate, to absorb CO2 a little and to counteract dry air.
- Use air purifier (with large air flow and several filters) or humidifier
- Employees should avoid strongly scented perfumes, creams, etc.
Less thick air in the office to increase well-being, concentration and performance through a healthy indoor climate is not witchcraft. If you consciously take the tips to heart and continuously monitor the air quality , you can go about your work without headaches and restrictions.
(Image: unsplash/ Alex Kotliarskyi)
