The levels of CO2 can tell us how good is the indoor air quality. CIBSE (www.cibse.org) has set some guidance levels for acceptable CO2 levels.
- Fresh: 600 ppm
- A little close: 800 ppm (equivalent to around 10 l/s per person ventilation rate)
- Close: 1,00 ppm (equivalent to around 8 l/s per person ventilation rate and the standard target ventilation)
- Very close: 1,200 ppm
- Very bad: 1,300 ppm