Legrizzly a écrit: |
Le premier article parle d'une étude faite par des chercheur du MIT, ce n'est pas des reptiliens.
Citation: | Pour enfoncer le clou, Martin Bazant et John Bush qui ont signé l'étude précisent que la règle de distanciation physique qui encourage les gens à s'éloigner socialement en public "n'a aucune base solide scientifique". |
Citation: | L'importance de la ventilation
Par ailleurs, l'étude confirme le caractère primordial de la ventilation dans la lutte contre les nouvelles contaminations. Ainsi selon le MIT, lorsqu'un espace est correctement ventilé, il "peut être exploité en toute sécurité même à pleine capacité".
Enfin, selon les auteurs, "ce n'est pas la distance sociale qui assure la sécurité des gens, c'est le temps qu'ils passent dans un endroit clos". Ainsi, ils estiment que "de nombreux espaces ont été fermés alors qu'ils n'avaient pas besoin de l'être". |
D'après l'étude; être à 2 m ou à 20 m avec un masque ne change rien, l'important est la ventilation des lieux |
Citation: |
"Furthermore, it underscores the need to minimize the sharing of indoor space, maintain adequate, once-through ventilation, and encourage the use of face masks."
"Thus, in the absence of masks, respiratory jets may pose a substantially greater risk than the well-mixed ambient."
"In both examples, the benefit of face masks is immediately apparent, since the CET limit is enhanced by a factor [...] Our inference of the efficacy of face masks in mitigating airborne transmission is roughly consistent with studies showing the benefits of mask use on COVID-19 transmission at the scales of both cities and countries (22, 33, 83).
Air filtration has a less dramatic effect than face mask use in increasing the CET bound."
"We note that the use of face masks will have a marked effect on respiratory jets, with the fluxes of both exhaled pathogen and momentum being reduced substantially at their source. Indeed, Chen et al. (42) note that, when masks are worn, the primary respiratory flow may be described in terms of a rising thermal plume, which is of significantly less risk to neighbors. With a population of individuals wearing face masks, the risk posed by respiratory jets will thus be largely eliminated, while that of the well-mixed ambient will remain."
"Finally, we reiterate that the wearing of masks largely eliminates the risk of respiratory jets, and so makes the well-mixed room approximation considered here all the more relevant."
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Citation: |
"The importance of adequate ventilation and mask use is made clear by our guideline. For normal occupancy and without masks, the safe time after an infected individual enters the classroom is 1.2 h for natural ventilation and 7.2 h with mechanical ventilation, according to the transient bound, SI Appendix, Eq. S8. Even with cloth mask use (pm=0.3), these bounds are increased dramatically, to 8 and 80 h, respectively. Assuming 6 h of indoor time per day, a school group wearing masks with adequate ventilation would thus be safe for longer than the recovery time for COVID-19 (7 d to 14 d), and school transmissions would be rare. " |