Publication - Advice and guidance

Coronavirus (COVID-19): ventilation guidance

Guidance to support the mixing of individuals safely in indoor domestic and commercial properties.

Coronavirus (COVID-19): ventilation guidance


The provision of fresh air into indoor environments is essential to preventing the spread of COVID-19. By taking measures to increase the volume of outside air entering a building, such as opening windows, doors or vents you can help minimise the risk of spreading COVID-19 to colleagues, friends, family members and customers.

We have developed this guidance to support the mixing of individuals safely in indoor domestic and commercial properties where this is necessary.


  • the circulation of air (ventilation/air conditioning) can reduce the risk of spreading COVID-19, however this must be in addition to other protective measures, such as physical distancing, enhanced hygiene regimes, face coverings and reduced occupancy
  • COVID-19 is spread through the air in droplets and aerosols (finer particles/ drops)
  • good ventilation helps reduce exposure by dispersing droplets and aerosols;
  • the most important thing to remember is to maximise the amount of fresh air coming into the premises
  • in many premises this will be done through opening vents, windows or doors
  • where there is mechanical ventilation, expert advice may be needed to ensure that the air pattern disperses the droplets and aerosols rather than just recirculates them
  • aerosol transmission should be one of the hazards considered in your COVID-19 risk assessment

Ventilation advice cards