COVID warning: The 6 feet social distancing rule is 85 years old and not safe!
Airborne Particles — what does it mean really? 6 feet?
The world must wake to and listen to scientists warning that SARS-CoV-2 can travel across rooms and between open spaces in buildings. There is no 6 feet rule, and 6 feet doesn’t mean safety! Many will die if this is not made very clear.
A report by Becky Spot published in Medium yesterday said:
Several months into the pandemic, we have been well educated about the 6 feet apart rule to keep social distancing. It’s worth asking, however: “Where did this rule come from?” Critically, it is based on work that was done in the 1930s by William F. Wells, et al., who measured the duration and distance it takes for large droplets to fall to the ground — on the basis of understanding the spread of tuberculosis. In fact, the presumption then was that the droplets were going to dry out and leave a virus exposed to the elements — desiccating within seconds. However, TB has proven to be very air-stable. The distance calculated by the 6-foot rule, also known as the d2 law, can only be applied to an isolated spherical water droplet.
In the decades since, there has been little push to examine or extend these ideas and Wells’ work became the rule of thumb for all medical agencies — including the WHO — in part because of necessity. Compounding all of this is the fact that everyone will go back inside as the winter months approach. We must have a look at the Wells’ assumptions again. In fact, we understand now that when someone coughs, sneezes, and breathes, significant numbers of droplets are smaller than 10 micron. In non-technical terms, that’s about 1/5 the diameter of a human hair, so small the human eye cannot really see them. We also know those droplets can travel up to 17 meters — and beyond — indoors, while any droplets smaller than 5 micron (1/10 the diameter of a human hair, if we are now splitting hairs) do not fall to the ground at all. They will travel in air currents until they are sucked into someone’s lungs, land and remain on a random surface, or find a circulating path through a ventilation system.