2024 Yes Human exposure to ozone in school and office indoor environments https://linkinghub.elsevier.com/retrieve/pii/S0160-4120(18)30996-6 Salonen, Heidi Multiple Countries Review Ozone (O3) Air pollution Ozone (O3) Indoor sources Outdoor sources School environments Office environments A global review found indoor ozone in schools/offices is typically below WHO limits, but can exceed them. Outdoor air is the main source. Reducing indoor ozone requires filtration, limiting ozone-emitting devices, and controlling reactive materials. 2018