MIT Researchers: People Not Safer From COVID Indoors at 6 Feet or 60 Feet Even With Masks, Recommend Fans and Ventilation
A new study by Massachusetts Institute of Technology (MIT) researchers says that the risk of being exposed to COVID indoors is as great at 60 feet as it is at 6 feet, even if people are wearing a mask, reports CNBC.
MIT professors Martin Z. Bazant, who teaches chemical engineering and applied mathematics, and John W.M. Bush, who teaches applied mathematics, published their results — which contradict 6-foot social distancing guidelines from the Centers for Disease Control and Prevention and the World Health Organization — in the Proceedings of the National Academy of Science.
The study found that pathogen-laced droplets travel through the air indoors when people talk, breathe or eat. The droplets mix with body heat, rise and travel throughout the entire room on air currents. People appear to be more exposed to this “background” air than droplets sneezed or coughed from a distance.
Bazant said in an interview that the problem is that COVID-19 hangs in the air of an indoor facility.
We argue there really isn’t much of a benefit to the 6-foot rule, especially when people are wearing masks. It really has no physical basis because the air a person is breathing while wearing a mask tends to rise and comes down elsewhere in the room so you’re more exposed to the average background than you are to a person at a distance...
This emphasis on distancing has been really misplaced from the very beginning. The CDC or WHO have never really provided justification for it, they’ve just said this is what you must do and the only justification I’m aware of, is based on studies of coughs and sneezes, where they look at the largest particles that might sediment onto the floor and even then it’s very approximate, you can certainly have longer or shorter range, large droplets.
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.
Bazant said the longer someone is inside with an infected person, the greater the chance of getting COVID. Bazant advised opening windows or installing new fans to keep the air moving, which could be just as effective or more effective than a new filtration system.
Bazant said that 20 people gathered inside for one minute is probably fine, but not over for several hours:
What our analysis continues to show is that many spaces that have been shut down in fact don’t need to be. Often times the space is large enough, the ventilation is good enough, the amount of time people spend together is such that those spaces can be safely operated even at full capacity and the scientific support for reduced capacity in those spaces is really not very good. I think if you run the numbers, even right now for many types of spaces you’d find that there is not a need for occupancy restrictions.