Dog owners know all the problems of their pets shedding fur in the vehicle. But there is another form of shedding that poses a more sticky problem: people shedding the COVID-19 virus.
We dump all of these particulates into the air any moment we cough or sneeze. Some are wide and large that you can see them tossed out of the nose or mouth of anyone.
In aerosol physics, these are "big" but invisible to the naked eye, and these settle very easily on surfaces. However, others are lightweight enough to be able to float in the air surrounding them.
This virus can be passed around more quickly than you know
What you may not know, however, is that this doesn't only happen when you sneeze or cough. When you're just chatting and even when you're just breathing naturally, you also emit aerosols.
Three reasons pose a special concern for this virus:
- Some, if not most, of the people who have it are asymptomatic. That means they had no idea they have COVID-19.
- Before they have signs, individuals may shed a high viral load from their throats.
- There is confirmation that a lot of this asymptomatic transmission is going on.
Virus shedding during regular conversation outdoors is not a concern since we can distance socially, and the wind quickly dilutes the airborne virus.
The typical apartment, also inside, has a capacity of about 1,000 cubic feet of air. Combined with an average household with an air exchange rate of around 0.5 air shifts every hour (meaning half of the air in the house changes per hour with outside air), this amount of room may help dilute the virus.
What about in our vehicles, then?
There is a capacity of around 100 cubic feet in the average family car interior, a 10th of an apartment scale. And maybe we'll jam four, or even five, people into that tiny room. It's hard to isolate oneself from culture.
As it relates to COVID-19, here is a possible problem. We have done an outstanding job of sealing up our vehicles over the decades. Ever note how silent they are these days on the inside? This is because every attempt has been taken to close up every potential void to seek improved acoustics. The consequence is that the amount of ventilation, how much fresh air reaches the vehicle, could be very limited.
This one little shift minimizes the probability
Experts modeled a basic scenario to illustrate what this implies for COVID-19 and to give you a simple move to protect yourself and others when in a vehicle: traveling with an infectious person in a car for 72 minutes, which seems fine other than coughing every few minutes.
When the windows are locked, SARS-CoV-2 accumulates in the vehicle cabin (in small aerosol particles). The concentration builds up with each fresh cough, with no noticeable dilution occurring. But this can be held at bay still by smashing one window open just 3 inches.
So the next time you're in the vehicle, if it's your own car with others or in a bus, Uber or Lyft, it's just the same advice: only raise the windows a little, even though everybody feels nice.
Ensure the vehicle is not in the recirculating air mode whether you utilize the air conditioning or heat and choose to leave the windows locked. Prefer the way that brings new outdoor air. In a taxi or ride-share vehicle, making everybody in the car wear a mask will also aid and is a necessity.
It is necessary to remember, say the researchers, that airflow modification is no replacement for mask-wearing by all occupants when inside a vehicle. And the results are restricted to future exposure to contaminants that may produce residual aerosols. The analysis did not model larger respiratory droplets, or the likelihood of the virus itself is contaminated.
Finally, just airborne propagation is tackled by taking in more outdoor weather. There are several elevated touch surfaces within a vehicle for droplets to fall on, so wash your hands during your ride.
Check out more news and information on COVID-19 on Science Times.
