Ventilation measurements and CO₂ exposure during sleep – How important is where you measure CO₂ in a bedroom?

Bedroom air distribution profiles are affected by the type of ventilation system and the human thermal plume and localized temperature gradients. The location of CO₂ measurements would impact breathing zone ventilation characteristics, such as air change per hour (ACH). A study, during heating season in a cold climate, is conducted in a NV bedroom equipped with trickle vents on windows. CO₂ sensors were placed at different locations of interest in a bedroom, such as vertically and horizontally around the breathing zone of a sleeping person, in the middle of the bedroom and near the door opening. The results of the various CO₂ measurements and the computed ACH values are presented in this paper. The study has provided some evidence on the importance and significance of the location of CO₂ measurements in and around the immediate breathing zone towards the determination of bedroom ventilation characteristics.