Coronavirus (COVID-19): ventilation
The risk of spreading coronavirus (COVID-19) is greater in poorly-ventilated areas. Good ventilation dilutes the amount of virus in the air and reduces the chance of infection.
What ventilation is and why it’s important
Ventilation is letting fresh air into indoor spaces and removing stale air.
If a person who has COVID-19 is present in a poorly-ventilated room, the amount of virus in the air can build up, increasing the risk of spreading COVID-19.
The virus may also stay in the air for some time after an infected person has left.
The more fresh air that moves through the room, the quicker any airborne virus will be removed from the room.
Keeping your home well-ventilated
Ventilation is most important if someone in your household has COVID-19, or when you have visitors in your home.
Opening windows and doors is the easiest way of improving ventilation. Also open any window vents or grilles.
Opening windows at opposite sides of the room or home is a good way of changing the air.
If it is safe, try to keep windows and vents open during the day.
If it's cold outside, it still helps if you can open the window even slightly to allow the air to circulate. Then open windows wider for short, sharp bursts of 10 to 15 minutes regularly throughout the day where it’s possible to do so.
If people are working in or visiting your home, try to let as much fresh air in:
- for a short time before they arrive
- while they are there
- after they have left
Try not to meet people in rooms with no windows or windows that don’t open.
Any actions to improve ventilation should not compromise other aspects of safety and security, especially if there are young children in the home.
Mechanical ventilation
If your home gets fresh air through air conditioning, make sure this is working and looked after properly.
Make sure it’s set to bring fresh air in and not just move indoor air around. If the air in your home is just moved around (recirculated), any coronavirus in the air will not get out.
You can also get more fresh air into your house by leaving extractor fans in bathrooms, toilets and kitchen areas running for longer than usual, with the door closed, after someone has been in the room.
Ventilation in the workplace
If you are going into a workplace, your employer should make sure it is safe for everyone to work in.
This may include control measures, such as avoiding certain activities or gatherings, restricting or reducing the duration of activities, and allowing ventilation breaks during or between room usage.
Your employer should give you guidance about how to get fresh air into your workplace.
However, any actions to improve ventilation should not compromise other aspects of safety and security (for example, avoid propping open fire doors), or your health and wellbeing from being too cold.
Ventilation in cars, taxis, vans, and buses
The risk of catching COVID-19 can be higher if you are sharing a small enclosed space with people not from your household.
If it’s safe to do so, opening doors of vehicles at stops or between different passengers will help to change the air quickly. Keeping windows open when the vehicle is moving or opening vehicle windows fully for a few minutes when stopped can also help clear the air.
If you must travel in a vehicle with other people, open the windows to let fresh air in.
If you need to travel, walk or cycle if you can.
If you’re using public transport, private taxis or coaches, or sharing a vehicle with people outside of your household or support bubble, wear a face covering and follow the guidance on safer travel.