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part of Indoor air quality
The CHEPA impact calculator is designed for use by school staff, building managers, and others responsible for making decisions about classroom environments. It supports informed decisions about the potential benefits of adding HEPA filter units in individual classrooms, by estimating how they could affect indoor air quality and energy use.
The tool was co-designed with school leaders and organizations supporting schools to ensure it is easy to use and reflects real classroom conditions. All inputs are based on everyday knowledge of classroom spaces – no technical expertise is needed.
For more detailed insights, the calculator can be combined with school energy audits or indoor air quality assessments to support conversations with local authorities, parent groups, or facilities providers about practical steps to improve classroom environments. CHEPA can be used alongside data from SAMHE (Schools’ Air quality Monitoring for Health and Education). While the two tools are not directly integrated, they are complementary: SAMHE provides live air quality data from classroom sensors, while CHEPA simulates the impact of installing a HEPA filter unit under specific conditions. Used together, they can help schools understand current air quality and explore practical options for improvement.
Project / A citizen science project monitoring indoor air, created with and for UK schools.
The CHEPA impact calculator was developed in partnership with Imperial College London, through a co-design process involving a range of partners (see the CHEPA website for partner details). Funding was provided by the Imperial College London UKRI Impact Acceleration Account (EPSRC grant number: EP/X52556X/1).
CHEPA is one of many projects by SEI York’s Inclusive Citizen Science group. Established in 2008, we are the longest-running academic research group on citizen science in the UK. We design and support projects that are accessible, equitable and impactful. Our work spans air quality, water quality, biodiversity, and health and wellbeing, enabling diverse communities to engage meaningfully with research and policy.
Try the calculator to explore how a HEPA filter unit might affect air quality and energy use in your classroom. Run your own simulation and get a personalized summary.
Project / We’ve delivered a co-designed web-based tool to enable schools to see the costs and benefits of installing HEPA filter units.
Project / A citizen science project monitoring indoor air, created with and for UK schools.
Project / CHILI aims to ensure that we support and improve children’s health and education as school and nursery buildings are adapted for energy efficiency.
Other publication / This two-page brief brings together SAMHE's findings and other evidence on air quality in UK schools and makes recommendations for policy and practice.
Journal article / SAMHE data shows that particulate matter levels in UK schools are heavily influenced by outdoor air quality.
Journal article / The SAMHE Web App was co-designed with schools to ensure maximum acceptance and engagement by teachers and pupils, as this is critical to the project's success.
