Hazardous indoor CO2 concentrations
were also measured in some dwellings by Viveiros et al. (2009,
2015a), and were correlated to barometric pressure decreases and
rainfall periods. Increases in the indoor CO2 were not only associated
with the occupants' habits during bad weather conditions, that
tend to reduce natural ventilation, but were also favoured by soil
gas flux increases. Despite the correlations established between
indoor CO2 and meteorological variables, no robust statistical
methodology was applied to the studies of Viveiros et al. (2009,
2015a) to evaluate the numerical significance of the environmental
variables as well as the percentage of influence of each
variable on the indoor CO2.