13. April 2026
Carbon Dioxide
As indicated, we often use CO2 to define how well air exchanges occur and how good the ventilation system within the building is.
We utilise the The BuiltAir from Nosmotech, because of its high grade sensors and circuit design. The module used is highly accurate, typically +/- 3% on a range of 0 to 10000 ppm, a ndir- non dispersive infra red monitoring unit.

So the type of monitor we see above is installed in to the compact multiparameter BuiltAir shown below. The application to apply the system within a school was chosen after much drowsiness and tiredness was reported in two identical classrooms.
A pre site visit showed that prolific damp was present on a number of walls. Strong pungent odour was present, as a function of the number of students present and the lack of any reasonable ventilation
Sampling in classrooms involves 2 x BuiltAir sensors of the type shown below per room.

The BuiltAir
The BuiltAir was originally designed for research purposes. This is becasue:
- The sensors used are high accuracy carbon dioxide sensor
- The BuiltAir monitor is configurable as a multi monitor synchronised system.
- The raw data and the uncertainty of a data set can be determined easily for each measurement
Sensor Specification

Where Airflow is not avaialbe
Where no direct airflow is able to be measured, either due to technology or because it is neglible, we can consider the levels of carbon dioxide as an indicator as to how effective the ventilation system is.
Carbon Dioxide Level

School Carbon dioxide level illustrated to be at 6500ppm
