CO2 monitors installed to support ventilation measures on campus

17 November 2021

CO2 monitor

As part of our Covid-secure measures on campus, the University has installed approximately 150 CO2 monitors to rooms in recent weeks.

Their introduction builds on significant work already undertaken to review ventilation in rooms across our campuses.

We release CO2 when we breathe out, so higher levels of CO2 in a room are related to higher occupancy and lower ventilation. Research shows that being in a room with fresh air can reduce the risk of infection from particles by over 70% - further detail and a video can be found on the Government website.

Latest Government and British Occupational Hygiene Society (BOHS) guidance has been utilised and the devices have been installed in rooms identified as being suitable and likely to benefit from being monitored. Assessments will continue to take place on whether additional CO2 monitors are required.

How do the monitors indicate CO2 levels?

The devices being introduced are pictured at the top of this page and data will be monitored by the University. This will help to ensure that our BOHS informed assessments are accurate, that ventilation systems and processes in rooms are effective and whether any further mitigations are required.

Measurement is also displayed on the monitor’s screen, with a green (lower), yellow (average) or red (higher) indication of CO2 level. If the data reaches a higher CO2 level, the monitor will also emit a small beeping noise. The measurement interval is set to five minutes to allow for a regular checking of CO2 levels in appropriate rooms.

What should I do if the monitor indicates a high level of CO2?

Should the monitor display a red indication level, CO2 levels can be reduced through increased ventilation by keeping windows and doors open wherever possible. Staff and students should continue to follow the University’s face covering policy. If required, a further action might be to leave the room for short periods of time.

Beyond this, the University is not asking staff or students to take any further action if the monitors demonstrate higher levels of CO2.

The devices are being monitored by the University so that further mitigations can be made to rooms in future as appropriate.

We have developed a set of frequently asked questions (FAQs) which provide further information on the CO2 monitors.

If you have any questions about ventilation in rooms or the new CO2 monitors after reading the FAQs, please email