The Indoor CO2 Map

Over the years I have posted links to a number of interactive maps which visualize the levels of carbon dioxide in the atmosphere. Human activities such as burning fossil fuels, deforestation, and industrial processes help to increase the concentration of CO₂ in the atmosphere. Higher concentrations of CO₂ enhance the greenhouse effect, leading to more heat being trapped in the atmosphere. This means that carbon dioxide plays a significant role in global heating.

Measuring CO₂ levels inside buildings can also be very useful. Like many people in the last couple of years I have begun to ignore all the preventative measures useful for avoiding infections transmitted via air (such as Covid-19). I no longer wear a mask in any situation and no longer avoid enclosed public indoor environments. However not everyone can be so blasé about the risks of infectious diseases.

Many individuals, such as the elderly, the immunocompromised, and those with preexisting health conditions, are at higher risk of severe illness or death from Covid-19 and so still need to wear face masks and avoid enclosed spaces.

The Indoor-CO₂ Atlas has been designed to provide a guide to the likely CO₂ levels in public buildings, eg shops, hospitals and cinemas. The map uses crowd-sourced measurement by the public to show recorded levels of CO₂ in individual buildings.

The concentration of CO₂ in an indoor environment can serve as a proxy for the amount of exhaled air present. Humans exhale CO₂, and higher concentrations can indicate poor ventilation and a higher presence of exhaled air. Since exhaled air can contain aerosols that may carry infectious viruses (like SARS-CoV-2), higher CO₂ levels can correlate with a higher risk of inhaling these infectious aerosols.

Anyone who has a mobile phone and a supported mobile CO₂-Monitor can contribute a reading to the Indoor-CO₂ Atlas. On the map colored markers are used to show the CO₂ levels recorded in a building. If you click on a marker you can also view a graph of the recorded CO₂ levels over time.