Coronavirus: Ventilation and air conditioning in the workplace

Why ventilation in the workplace is important


Adequate ventilation reduces how much virus is in the air. It helps reduce the risk from aerosol transmission.

Aerosol transmission can happen when someone breathes in small particles in the air (aerosols) after a person with the virus has been in the same enclosed area. Aerosols can remain suspended in air for long periods of time and travel distances greater than 2 metres.

The risk from aerosols is greater in areas that are poorly ventilated.

Although ventilation reduces the risk from aerosols, it has minimal impact on:

  • droplet transmission (from people being in close contact)
  • contact transmission (touching surfaces)

See prevent the spread of coronavirus in the workplace for advice on reducing these types of transmission.

Your ventilation is likely to be adequate to minimise the risk of COVID-19 aerosol transmission if the rooms or spaces in your building(s) are:

  • used within the occupancy limits specified in the building design, and
  • have a sufficient fresh air supply to meet the current minimum building standard. You can get advice from a competent ventilation engineer or, as a precautionary approach, operate your system on the maximum air flow rate

Assessing the risk of aerosol transmission

Adequate ventilation can look different depending on the workplace or setting.

You can reduce the risk of aerosol transmission by:

  • making sure infected workers (or anyone with COVID-19 symptoms) do not come into the workplace
  • providing adequate ventilation with fresh air

Deciding what adequate ventilation looks like in your workplace should be part of a risk assessment.

When you have completed an assessment, the Health and Safety Executive in Great Britain have produced guidance on improving ventilation in the workplace.

You should also make sure any control measures you identify by your risk assessment take account of the latest public health regulations and guidance.

Video on using ventilation to tackle COVID-19

The following video gives basic advice on how you can use ventilation to help reduce the risk of COVID-19 transmission in your workplace.