ArticleCurrent efforts to minimize energy losses and maximize energy savings for heating of
all houses are most often gained by insulating facades and replacing windows. However, these
measures can have a significant negative
impact on human health and these problems can occur
in buildings with a high concentration of people, such as school buildings. The aim of this paper
is to analyse the results of measurements of air temperature, relative air humidity and carbon
dioxide in
winter period in the classrooms of two universities, Estonian University of Life
Sciences (EULS) in Tartu and Czech University of Life Sciences (CULS) in Prague. The
measurements have carried out in 2017
2018 in eight classrooms of the EULS and two
classr
ooms of the CULS. The external and internal temperature, relative humidity and
concentration of carbon dioxide have measured in the classrooms during a few days in the winter
period. In the lecture rooms of CULS, when the air conditioning was off, the leve
ls of CO
2
exceeded the recommended levels about two times. The average internal temperature and CO
2
concentrations in the classrooms of EULS follows the norms and refers on good ventilation. The
extremely low relative humidity in the classrooms of EULS at
17.1
±
2.6% refers to a high risk
of allostatic load and respiratory symptoms among students. It is important to pay attention on
regular ventilation and relative air humidity control in the teaching rooms, especially with high
number of students to preven
t seasonal sickness of upper respiratory tract