Update: Government Ventilation Guidance

As global research into the spread of COVID-19 continues, there is mounting evidence to suggest that airborne aerosols are a key transmission route of the virus, as such the government are urging us to increase ventilation in indoor spaces.

What is airborne transmission?

When someone with COVID-19 breathes, speaks, coughs or sneezes, they release droplets and aerosols containing the virus. While larger droplets fall quickly to the ground, the aerosols containing the virus can remain suspended in the air, and if someone breathes those particles, they can become infected with COVID-19. This is known as airborne transmission.

What does the science say?

If an asymptomatic person is unaware of their infection and is living or working in a poorly ventilated room, each time they breathe, speak, cough or sneeze, the amount of virus in the air will build up. If other people are breathing in the same space, the risk of spreading COVID-19 via airborne transmission is increased. The risk is increased further if there are lots of infected people in the room. It is also important to note that the virus will remain in the air after an infected person has left.

Bringing fresh air into a room and removing older stale air that contains virus particles reduces the chance of spreading COVID-19. The more fresh air that is brought inside, the quicker any airborne virus will be removed from the room. In 2020, Public health England explained that “a single air change is estimated to remove 63% of airborne contaminants... and after 5 air changes, less than 1% of the original airborne contamination is thought to remain”.

New Guidance

As a result, the government have released new guidance on how to increase ventilation in indoor spaces. The full government guidance can be found here, however if you would prefer an ‘easy-to-digest’ version, you can download a copy of our latest whitepaper here.