A new paper on new coronavirus infection control points out that 4 to 5 meters and bicycles need to be 10 meters away when walking behind people

A joint study between Belgium and the Netherlands has shown that the virus may be widely spread in

slipstreams that occur near moving people.

Social Distancing v2.0: During Walking, Running and Cycling
(PDF file) http://www.urbanphysics.net/Social%20Distancing%20v20_White_Paper.pdf

Belgian-Dutch Study: Why in times of COVID-19 you can not walk / run / bike close to each other.

Coronavirus: Walkers, runners and cyclists should avoid 'slipstreams' when social distancing, research claims | The Independent

The new coronavirus infection is one of the main routes of transmission, which involves sneezing and coughing. Therefore, it is strongly recommended to 'take a social distance of about 2 m' as a measure to prevent the spread of infection.

A movie that allows experts to easily explain `` specific methods for taking social distance '' effective for new type coronavirus measures-gigazine

The best way to maintain social distance is to refrain from unnecessary and urgent outings, but sometimes it is necessary to go out, and it is necessary to `` exercise moderately '' to increase immunity The house is recommended .

Researchers at Eindhoven University of Technology in the Netherlands and Catholic University of Leuven in Belgium simulated the movement of saliva caused by breathing and coughing during running, and said, `` Under mild weather. So, two runners ran at a speed of 14 km / h. '

The following figure simulates the situation where the flying sticker attaches to the clothes of the runners behind from the front runner. Mist-like colorful points extending from the runner are flying, and those near red indicate large diameter and those near blue indicate small diameter.

'Simulations have clearly shown the effects of runners leaving space in flight. These fly sneezes and sneezes can cause significant damage,' said Bad Brocken, an aerodynamics expert at Eindhoven University of Technology. However, it can also be caused by simply breathing, where the red dots represent large flying particles that fall relatively quickly, but the fine dots shown by the blue dots Fly lashes adhere to clothes. '

It is said that such flying does not simply float on the spot, but directly hits the person behind by riding a slip stream that is the airflow generated behind the moving object.

'Slipstreams are areas just behind a moving person, causing a slight stretch of the air. These slipstreams are well known among cyclists,' says Brocken. However, it also occurs behind people who are walking or running.Our research shows that no matter how the slip stream is formed, the flying droplets ride on the stream of air That's why it's best to avoid slipstreaming behind people. '

Even when walking at a speed of 4 km / h, the result is that the flying clouds generated by breathing etc. reach the people walking behind.

'This work was done by aerodynamics experts, not virology, so we evaluated the risk of traveling in the air, It's not about risk. ' Also, it is said that the paper of this research result has not been peer-reviewed yet, but it took several months to release it if waiting for peer-review, so he decided to make a presentation.

Brocken added, 'If you walk behind a person, you need to stay at least 4-5m away. This is 10m for running or slow cycling, 20m for fast cycling, and 20m for passing. It is advisable to move a long distance in front of you and avoid walking in front of people. Similarly, if you are overtaking a person ahead of you on a bicycle, be very far in the line. ' I was talking.

in Ride,   Science, Posted by log1l_ks