4. How to improve natural ventilation

You can improve natural ventilation by fully or partially opening windows, air vents and doors. Don’t prop fire doors open. 

Buildings are designed to provide an adequate amount of ventilation and, where this is through windows and air vents, you should be able to open them. If they cannot be opened, the ventilation in that area will be affected. 

If you identify an area that requires improvement, you should decide if that area should continue to be used until improvements are made.

It is important not to close windows or doors completely when people are using or occupying a naturally ventilated area. This can result in very low levels of ventilation. 

Lower temperatures and windy weather conditions in the winter months will increase natural ventilation through openings. This means you don’t need to open windows and doors as wide. Look to see if trickle vents can be opened. There is more advice on balancing ventilation with keeping warm.

Purging (airing rooms)

Airing rooms as frequently as you can improves ventilation. Open all the doors and windows fully to maximise the ventilation in a room. It may be better to do this when the room is unoccupied.

Talking to your workers about improving ventilation

Making sure an area has enough fresh air through natural ventilation relies on people doing what is expected of them. You should explain the reason for adequate ventilation to workers so they can play their part in reducing the risk.

This page is reviewed regularly and updated to reflect any changes in the guidance.

Page last reviewed: 30 April 2021

Next review due: 31 May 2021

Updated 2021-03-31