Recommended Distances Between Persons When Walking, Running, Biking, or Cycling During COVID-19 Times
A Belgian-Dutch study has released the results of a simulation that looked into the safe distances when you are walking, running or cycling with others during this COVID-19 epidemic.
“If someone exhales, coughs or sneezes while walking, running or cycling, most of the microdroplets are entrained in the wake or slipstream behind the runner or cyclist. The other person who runs or cycles just behind this leading person in the slipstream then moves through that cloud of droplets,” says Bert Blocken, professor of civil engineering at Eindhoven University of Technology and KU Leuven.
“The slipstream is the zone that arises right behind a person when they are walking or cycling, and which pulls the air a bit along with this moving person, as it were,” explains Blocken. “Cyclists like to position themselves in the slipstream of others to reduce their air resistance. But someone who walks or runs also has such a slipstream. We have seen that no matter how that zone forms, droplets end up in that airstream. So it’s best to avoid that slipstream”, says Blocken.
Here are the suggested safe distances between moving persons:
Walking (same line & direction) –> at least 4 to 5 meters
Running or slow biking —-> at least 10 meters
Fast biking —-> at least 20 meters
When passing someone it is advised to be in different lane at a considerable distance e.g. 20 meters for biking.
“People who sneeze or cough spread the droplets with greater thrust, but also those who only exhale emit droplets. “The red dots on the images represent the largest particles. These are generally considered to be the most contagious – although virology research should confirm this for COVID?19 – and fall down faster.” But when someone walks through that droplet cloud, they can still end up on that person’s body”, explains the scientist.
According to the scientists, the 1.5 meter distance rule announced by several governments is “very effective” for people who stand still indoors or outdoors in calm weather.
Blocken tweeted this: “Cycling & running are not big risks for #COVID19 spread. But moving closely in slipstream is. This holds everywhere, also when walking in supermarkets, shops, etc. No need at all to ban running or cycling.”
Strictly correct but could be misinterpreted. Cycling & running are not big risks for #COVID19 spread. But moving closely in slipstream is. This holds everywhere, also when walking in supermarkets, shops, etc. No need at all to ban running or cycling. #COVID #coronavirus https://t.co/IvsViNzxvN
— Bert Blocken (@BertBlocken) April 9, 2020
More tweets from Blocken about the study:
(2/2) It was a race against clock to get results ready, confirmed, validated & animated. Not having full article yet = collateral damage for us wanting to communicate to public asap. Mind you: we validated with wind tunnel & ensured quality.#COVID?19 #COVID #coronavirus
— Bert Blocken (@BertBlocken) April 8, 2020
Bit more text explaining research findings & why we communicate now, not later: White Paper:
— Bert Blocken (@BertBlocken) April 8, 2020
COVID19 Social Distancing v2.0: During Walking, Running Cycling: https://t.co/FHzhHVeWrX#COVID19 #COVID?19 #COVID #COVID2019 #coronadebat #coronavirus @TUeindhoven @LeuvenU @ANSYS https://t.co/9BpLkw7qEd
3. http://www.urbanphysics.net/Social%20Distancing%20v20_White_Paper.pdf