Finding F-0428

“These results show that the classroom average concentration of carbon dioxide often exceeds the value of 1500 ppm, during its full occupancy, which indicates inadequate ventilation.”

Impact of CO2 concentration on indoor air quality and correlation with relative humidity and indoor air temperature in school buildings, Serbia (2015). Page 2. CKB 0335

Structure

Factor: Carbon dioxide (CO₂)
Population: elementary school children
Setting: classroom, RS
Study design: measurement campaigns of CO2, indoor air temperature and relative humidity in classrooms of four naturally ventilated elementary schools in Serbia (three urban, one rural) in heating and non-heating seasons, with outdoor reference measurements (class 4)
Caveat: 'often' is not quantified in the sentence

A Finding records what one published document states, verbatim and with its page. It is not a conclusion of Coridum; see the Claims that build on it.