a separation of one meter is not enough

Astonishing. Numerical simulation shows that social distancing measures are insufficient to be truly effective. Performed by Ansys, this study questions and should encourage us to space each other more than the recommended meter. Thierry Marchal, Health Director at Ansys, answers our questions.

Among the simple steps everyone can take to protect themselves from theepidemic of Covid-19 and slow its progression, the barrier gestures and social distancing measures are the most commonly recommended and used.

While it is recommended to observe a distance of one meter between individuals, a Numerical simulation shows that these social distancing measures are insufficient to be truly effective! Produced by Ansys, global specialist in Numerical simulation, This simulation questions. Following this study, it would be interesting to hear the opinion of the political and health authorities who decided this barrier gesture.

This simulation shows that the recommended distances of one meter are not significant enough to be effective. © Ansys, YouTube

Are the distances recommended by health and political authorities significant enough to be really effective? If we trust this study, the answer is clearly no. The distance of one meter recommended is obviously not sufficient.

Insufficient social distancing recommendations

To reach this conclusion, Ansys simulated the propagation of the droplets responsible for the transmission of virus during an interaction between several individuals and during the practice of a sport. The modelization demonstrates that droplets can be expelled up to 28 meters per second during a cough or sneeze. The distance between two static people should therefore be at least two meters, double the distance currently recommended.

As for people practicing a sport and who breathe by definition stronger during exercise, greater distances between each individual must be respected. A runner should respect a distance of three meters minimum and cyclists of 10 meters.

Simulation of the spread of droplets during physical exercises. © Ansys

Thierry Marchal, Health Director at Ansys, answers our questions:

Why did you do this study?

Thierry Marchal: Numerical simulation is a great technology that makes it possible to predict and visualize things that are sometimes difficult to measure in order to better understand and improve phenomena. It is therefore an ideal technology for educating through image and understanding. From the start of the pandemic, Ansys wanted to exploit this technology for the good of the population. The purpose of this research is to inform the general public about behaviors that can protect against the risk of contamination Covid-19 and to help healthcare professionals reduce these risks in hospitals and other healthcare facilities. In addition, the results of these simulations provide useful lessons on the effectiveness of the recommended barrier measures or even adjust recommendations.

How do you simulate the spread of droplets?

Thierry Marchal: The droplets are spheres of liquid that spread in theair. These behaviors are widely studied in search engines. car, chemical, pharmaceutical sprays, etc. From scientific studies on the subject, we know what are the sizes of the droplets coming out of the mouth as well as their speed expulsion if a person breathes, coughs or sneezes. We therefore use existing and widely validated technologies and adapt them to health. It is therefore possible to simulate the propagation of droplets using software modeling fluid dynamics by acting on several parameters: presence of wind or not, size and relative position of people around the subject being studied.

Have you calculated the risk of being infected with Covid-19 depending on whether you are 1, 1.5 meters or 2 meters from another person?

Thierry Marchal: Research conducted by Ansys shows that a distance of one meter is insufficient to protect against contamination by Covid-19. Indeed, at this distance, the droplets expelled during a sneeze or a coughing fit can travel up to 28 m / s under certain conditions and do not have time to fall back to the ground under the effect of the gravity. After 1.5 meters or 2 meters, the majority of the droplets, matter of volume reach the ground. The risk of contamination is lower, but the zero risk does not exist however.

This will also interest you

Coronavirus: tomorrow, all masked? SARS-CoV-2. It appeared in China in December 2019. Since then, it has claimed tens of thousands of lives worldwide. To limit the spread of this coronavirus and in the absence of treatment or vaccine, various measures have been devised. Among them, the wearing of a mask.

Did you like this article ? Don't hesitate to share it with your friends and help us to promote ABSMARTHEALTH :)! The editorial team thanks you.