Bad indoor air quality is more than just CO2

When I read articles and blog posts about indoor air quality, I am always happy to see that this topic is becoming more important day-by-day. Facts which are stressed over and over again are

  • over 90% per day, we spend indoors
  • bad indoor air quality is about 60% to 80% more harmful than bad outdoor air quality
  • open your windows every once in a while
  • implement ventilation systems in your house

…but there is one other thing, which is stressed by many authors:

  • CO2 is a defining component of bad indoor air quality.

…so with this blog post, I wanna point out, that CO2 is definitely one major component, but not THE major air pollutant defining bad air. It’s a combination of particles (PM2.5), VOCs (Volatile Organic Compounds) and CO2 (Carbon dioxide). Additionally, the temperature and humidity inside buildings has a huge effect on the development of odours distributed from mold or bacteria in general. (cf. Memphis Mold Inspector, 2015) In the following I want to stress the impact of volatile organic compounds.

VOCs are typically emitted by furniture, carpets, wallpapers, paints and many more. However, often one major influencing factor is missing – the human body (cf. Shirasu & Touhara, 2011; ). dane-deaner-541785-unsplash.jpgBreathing and body odours define the indoor air quality. This is also one reason, why the air becomes worse in meeting rooms. They are often small, not (well) ventilated. The smaller the room and the more people participate in the meeting, air quality becomes increasingly worse. Probably you experienced it yourself – you become tired or less concentrated during the meeting. Also headaches can be a consequence of bad air quality.

(Health Effects Institute, 2018)

This year’s ‘State of Global Air’ – report shows, that in 2016, more than 2.6 million deaths were caused by household pollution. This results in rank eight in risk factors for early deaths. (cf. Health Effects Institute, 2018)

So volatile organic compounds, in general, are not highly dangerous – but it should be taken care of to keep the level as low as possible, to ensure productivity at work and a healthy life style at home.

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Shirasu, M., Touhara, K. (2011). The Journal of Biochemistry: The scent of disease: volatile organic compounds of the human body related to disease and disorder. 150(3), pp. 257–266,

Uniform Resource Locator

Memphis Mold Inspector. The seven components of indoor air quality, retrieved from:


Health Effects Institute. 2018. State of Global Air 2018. Special Report. Boston, MA:Health Effects Institute, retrieved from: