CO₂-based ventilation & safety system for schools
A practical, replicable approach to reduce indoor contagion risk by combining room-volume modeling, occupancy dynamics, ventilation capacity, and real-time CO₂ monitoring.
I designed a system that takes into account the volumetric calculation of each room, the average number of people occupying the space, the rotation of individuals throughout the day, and the direct or cross-ventilation capacities of each classroom.
To monitor air quality in a simple and actionable way, we installed CO₂ sensors in every room. These sensors were configured to emit sounds that helped staff make immediate decisions: when to ventilate, when to temporarily evacuate the space, or when to apply other mitigation actions.
This project was carried out without any intention of profit. Our motivation was to protect the well-being of students, teachers, and staff during a challenging time, and to share an approach that could be replicated by other schools or public spaces.
“The goal was not to build a perfect system — it was to build a system that any school could actually apply.”
CO₂ is a useful indicator because it is affordable, measurable, and easy to replicate. While more advanced systems exist, CO₂ stands out as a practical proxy for ventilation quality: when a room is occupied, CO₂ increases due to respiration, and in poorly ventilated environments this correlates with a higher probability of airborne transmission risk.
The approach considers ventilation characteristics (for example, air changes per hour) together with room volume, average occupancy, and time spent inside. In practice, this provides guidance on how long a space can remain safely occupied before ventilation becomes necessary.
By combining real-time CO₂ monitoring with simple operational actions (ventilate / pause activity / rotate occupants), schools can create safer environments while keeping the solution economically accessible and technically reproducible.