From the very beginning, the concept revolved around having as much air available for the CO2 sensor to do its job. The first iterations for the node had a towered design with a steel mesh covering almost 360 degrees. I liked this design, but it proved to be a bit difficult for construction. The meshes were either too rigid to bend to a cylindrical shape, or too flimsy to keep that shape.

Additionally, these units would be too fragile, and even a slight bump may damage, dent or even break them. So it was time to move to a single body shape.

PCB design was already underway so we had three main components for the nodes: 

- the main board,

- an independent pcb for the CO2 sensor, 

- a second independent PCB for the air quality sensor.