A brief guide to using CO₂ monitors and air cleaning units in schools

Keeping educational spaces well-ventilated can reduce disease transmission, improve pupils’ alertness and concentration and can help to improve indoor air quality – here’s a brief guide on how to use CO₂ monitors and air cleaning units effectively in your school

CREDIT: This is an edited version of an article that originally appeared on gov.uk

Between 2021 to 2023 the Department for Education (DfE) provided all state-funded education settings with CO₂ monitors to help them monitor ventilation and some with air cleaning units (ACUs), to help improve air quality in poorly ventilated spaces.

These devices need to be used consistently to manage ventilation.

CO₂ monitors

CO₂ monitors provide a way of identifying the level of CO₂ in a space, which informs us how much of the air we are breathing in has been breathed out by others.

These monitors should be used regularly to help you identify when to take steps to improve ventilation and provide reassurance that existing ventilation measures are working.

Knowing when ventilation measures should be increased or can be decreased can also help keep classrooms warm and conserve energy. 

Understanding what to do with your readings

You can download and display this CO₂ monitoring factsheet next to your monitors to inform users of the action to take based on your CO₂ monitor readings.

Air cleaning units

ACUs can help you to reduce airborne contaminants in poorly ventilated spaces. ACUs do not reduce CO₂ levels or improve ventilation.

Maintaining your air cleaning unit

ACUs require regular maintenance, including regular cleaning and the need to purchase replacement filters. The frequency of maintenance and the cost of replacement filters will vary depending on level of use and the specification of the device. The unit will notify you when a filter change is required.

DfE-funded ACUs included:

• Dyson TP09
• Camfil City M

Please see the manufacturer’s guidance for the type of unit you received for details on maintenance requirements.

Buying new air cleaning units

You can buy new or replacement devices through DfE’s Find a Framework service.

The ACUs recommended by DfE are known as HEPA (high efficiency particulate air) filtration units. its. Further details on the minimum recommended specification for ACUs in education and care settings is in this technical specification.