Minimising the risk of COVID-19 in the built environment is the topic of the latest CIBSE Journal podcast. The authors of CIBSE’s COVID-19 Ventilation Guidance discuss the physics of virus transmission and how the infection risk can be minimised in buildings. Appearing on the podcast are Dr Shaun Fitzgerald, director, Centre for Climate Repair, University of Cambridge; Eimear Moloney director at Hoare Lea; Dr Chris Iddon, chair of the CIBSE Natural Ventilation Group and Abigail Hathway, lecturer at the University of Sheffield.