A scientific study recently published in a Spain has shown how rapidly coronavirus can spread in indoor settings with little or no ventilation such as family homes, offices, restaurants and classrooms.
Coronavirus is spread through the air, especially in indoor spaces and scientists now openly acknowledge the role played by the transmission of aerosols – tiny contagious particles exhaled by an infected person that remain suspended in the air of an indoor environment.
At present, health authorities recognize that there are three ways that corona virus is transmitted: the small droplets from speaking or coughing, which can end up in the eyes, mouth or nose of people standing nearby; contaminated surfaces (fomites) and transmission by aerosols – the inhalation of invisible infectious particles exhaled by an infected person that, once leaving the mouth, behave in a similar way to smoke. Without ventilation or adequate filtration, aerosols remain suspended in the air and become increasingly dense as time passes.
At the beginning of the pandemic, it was believed that the main airborne transmission of coronavirus was via the large droplets we expel when we cough or sneeze. However it is now known that shouting, singing and even just talking inside, in poorly ventilated rooms over a prolonged period of time also increases the risk of contagion. These aerosols, if not diffused through ventilation or mechanical filtration, become increasingly concentrated, which increases the risk of infection. Scientists have now shown that these particles – which we also release into the atmosphere when simply breathing and which can escape from improperly worn face masks – can infect people who spend more than a few minutes within a five-meter radius of an infected person, depending on the length of time and the nature of the interaction.
As a result of these findings, it is recommended that rooms should be naturally ventilated or a mechanical filtration system used where possible. The study concluded that the rate of transmission can be greatly reduced simply by properly ventilating the room. In the spring and summer months, this can easily be done by opening a door or window. However in many cases this is not possible. In the winter months it can be too cold and in some circumstances, it may not be convenient to safely leave a window open; and in some cases there may not even be one.
If there is no convenient option to naturally ventilate a room, a mechanical option may be the next best thing. An Air Purifier, with a hospital grade HEPA13 filter can clean the air of an averaged size room is as little as 20 minutes. When used in conjunction with other best practises such as social distancing, hand washing and mask wearing, an air purifier can help reduce the spread and transmission of COVID19 in dangerous indoor settings, with little or no, natural ventilation.