What is the role of air conditioning or fans in the spread of Covid-19? Faced with rising temperatures, this question is on everyone’s lips. The HSCP, the French Ministry of Health and Public Health have spoken on the subject. What is it really ?
At the end of April 2020, Chinese researchers had identified a chain of transmission of the virus in a restaurant and had estimated that the air conditioning was the cause. “A strong flow of air from the air conditioner may have spread droplets“, they had then suggested. A scenario questioned by other experts, such as Daniel Camus, infectious disease specialist at the Institut Pasteur de Lille: “The ventilation, ventilation or air conditioning systems have not been shown to present any particular danger. Viral loads are probably insufficient.”, he explained to West France.
Covid-19: Does ventilation promote the spread of the virus?
In an opinion published in early May, the High Council of Public Health (HCSP) explained that the use of these devices did not pose a problem when an individual was alone in a room. “But in the event of grouping of people in a common room, many hypotheses and questions start from the principle that there is a risk of associating in the same room infected people and healthy people because of the asymptomatic possible of the attack by the Covid-19 “, specified the document. The dreaded scenario? That these devices cause aerosolization of the viral particles, thus promoting contamination.
Are the risks of spreading the virus the same with an air conditioning and a fan? In a summary published on July 23, Santé Publique France explained that “the use of a fan in a room in the presence of several people, some of whom are contagious, make it viral load homogeneous in the room and its average level will depend on the ventilation system (…) By creating a significant air movement, the device will project the respiratory droplets emitted by people at a distance into the room and render inoperative the safety distance between the people”, the document stated.
What about air conditioners? Public Health France explains that the latter must “be equipped with efficient filters and properly maintained. They then allow to obtain ‘filtered’ air which significantly lowers the viral load of the room if one or more infected people are in the room”. The risks of contamination would therefore be low.
Air conditioning and fan: how to limit the risk of contamination?
To limit the risk of the coronavirus spreading through ventilators or air conditioning, the HSCP and the Ministry of Health deliver their recommendations:
- ensure that maintenance is respected and look for the most efficient filter in terms of sanitation if you use an air conditioning system;
- if you are using a fan, stop the appliance when another person enters the room;
- do not use a fan in collective spaces with small volumes in the absence of air conditioning, even if people in the room wear a mask;
- Regardless of the type of device used, ventilate your interior at least twice a day, for 10 to 15 minutes.