They also discussed what people can do to protect themselves. “Wearing face coverings to decrease airborne exposure risk is critical,” they wrote, and “reducing the amount of time you spend in poorly ventilated, crowded areas is a good way to reduce airborne exposure risk.”The common advice for social distancing is to stay 6 feet apart. It’s easy to remember, but it doesn’t account for all aerosol risks – particularly indoors.
Because people infected with SARS-CoV-2 can transmit large amounts of the virus, there is no safe distance in a poorly ventilated room, Erath, Ferro, Ahmadi and their Clarkson University colleague wrote in a second article. Air currents from a fan or ventilation system can spread respiratory droplets farther than 6 feet. So can speaking loudly or singing, as superspreader events have shown.“Over time, it won’t matter where you are in the room,” they wrote. “While it’s not a perfect analogy, picturing how cigarette smoke moves through different environments, both indoors and outdoors, can help in visualizing how virus-laden droplets circulate in the air.
A simulation shows the trajectories of droplets emitted by someone in a room with mixed ventilation. Credit: Goodarz Ahmadi and Mazyar Salmanzadeh / Clarkson University.A large number of COVID-19 cases have come from “superspreader” events where someone who is highly infectious spreads the virus to dozens of others.
Researchers in Hong Kong recently estimated that about 20% of the people infected there were responsible for