Importance of moving activities outdoors and ensuring proper ventilation indoors stressed, as experts urge science community to clarify definitions — ScienceDaily

Scientists affiliated with leading research institutions across the U.S. state in a letter published Monday in the journal Science that researchers across disciplines must converge to deliver clear public health guidance about how SARS-CoV-2 is spread in the air.

The researchers write in the open letter that the scientific community must clarify the terminology used related to aerosols and droplets, and employ a more modern size threshold, rather than the existing one based on 1930s-era work. Authors include experts from the University of California San Diego, University of Maryland, Virginia Tech, and others.

Public health officials should make a clear distinction between droplets ejected by coughing or sneezing — which have inspired the social distancing mantra of six feet of separation between people — and aerosols that can carry the virus for much greater distances. Viruses in aerosols smaller than 100 microns can remain airborne in a confined space for

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Many ventilation systems may increase risk of COVID-19 exposure, study suggests — ScienceDaily

Ventilation systems in many modern office buildings, which are designed to keep temperatures comfortable and increase energy efficiency, may increase the risk of exposure to the coronavirus, particularly during the coming winter, according to research published in the Journal of Fluid Mechanics.

A team from the University of Cambridge found that widely-used ‘mixing ventilation’ systems, which are designed to keep conditions uniform in all parts of the room, disperse airborne contaminants evenly throughout the space. These contaminants may include droplets and aerosols, potentially containing viruses.

The research has highlighted the importance of good ventilation and mask-wearing in keeping the contaminant concentration to a minimum level and hence mitigating the risk of transmission of SARS-CoV-2, the virus that causes COVID-19.

The evidence increasingly indicates that the virus is spread primarily through larger droplets and smaller aerosols, which are expelled when we cough, sneeze, laugh, talk or breathe. In addition, the

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