In California’s 2020 School Reopening Ventilation and Energy Efficiency Verification and Repair Program legislation, the importance of CO2 monitoring in schools is highlighted, “To ensure proper ventilation is maintained throughout the school year, all classrooms shall be equipped with a carbon dioxide monitor.”
An article on bbc.com explains how we need to introduce a good supply of fresh air into classrooms. https://www.bbc.com/news/health-56268188
‘So, one option is to use carbon dioxide monitors – devices costing between £50-£200 that keep track of the gas and tell you how much of it there is.
They can’t detect infectious aerosols, but they can act as a warning that there may be a problem.’


The Honeywell Transmission Risk Air Monitor
The Honeywell Transmission Risk Air Monitor- A cost-effective monitor for use in schools, restaurants, and other small-to-medium sized buildings that alert to the potential increase of exposure to airborne transmission risk based on CO2 and activity levels in an indoor area.
Using this guidance and Honeywell algorithms, we developed risk levels based on common activities and average variables such as room size, number of people present, breathing rate, and duration. The device comes with three pre-programmed indoor activity settings: low activity (movie theatres, libraries, and classrooms), medium activity (restaurants, offices, small clinics), and high activity (gyms, indoor arenas, recreation centres) and is recommended for coverage of 800-1000 square feet. For each setting, the monitor provides indications using a traffic light pattern (green, yellow, or red) and a sound alarm so users can be aware of the potential increase of airborne transmission risk based on detectable CO2 levels.
WHY SCHOOLS?
- Pressure to go back to “in person” learning.
- Average class size: 19 students / classroom and average classroom size is 900 ft2 (crowded in small space).
- Potential for lack of upgraded HVAC and ventilation systems.
- Limited funding to upgrade ventilation system, but could fund small purchases on filters, air purifiers, and low-cost air monitors like Honeywell Transmission Risk Air Monitor.
WHY RESTAURANTS?
- Long duration in public, enclosed area: ~90 min.
- Eating and loud speaking increase CO2.
- Cooking at home fatigue, people may take more risk to go out.
- Peace of mind for customers & employees.