Posted 2 years ago
According to MIT researchers, the widely used 6-foot rule does little to prevent COVID-9 exposure indoors and is based on outdated understanding of how the coronavirus moves in closed spaces. The study found the risk of exposure from an infected person is similar at 6 feet and 60 feet. They said other variables - like the number of people in a space, whether they wear masks, what they are doing, and the level of ventilation - were much more important.
Martin Bazant and John Bush, both MIT professors in applies mathematics, developed a formula to estimate how long it would take for a person to hit dangerous levels of exposure from one infected person entering a room. Using this calculation, it could be that the level of exposure is high in some spaces even if people are more than 6 feet away. It could also be lower than expected.
Scientific understanding of how the coronavirus moves in the air has challenged earlier assumptions about how best to adapt to minimize its spread. At the beginning of the pandemic, it was widely believed that the virus traveled via heavier droplets ejected during exhalation, sneezing, or speaking. But evidence has long suggested that the virus instead floats around on lighter aerosol droplets that can stay suspended in the air and travel much farther than first thought.
Bazant said: "The distancing isn't helping you that much, and it's also giving you a false sense of security because you're as safe at 6 feet as you are at 60 feet if you're indoors. Everyone in that space is at roughly the same risk, actually,". According to the model, if an infected person walks into a restaurant, where nobody is wearing a mask all people would be at risk within 36 minutes no matter if people were 6 feet apart or not. By contrast, if all 25 people in that room were wearing a mask, the air would be safe to breathe for 20 hours, it said. Alternatively if they were singing instead of speaking/eating, without masks, they would be at risk within 3 minutes.
Topic: US News
Tags: Covid-19 CDC Covid Mask Social Distancing