Why 1.5m might not be far enough

Current guidelines to prevent the transmission of SARS-CoV-2 don't go the distance, says expert in fluid dynamics

Oh, the good ol’ days, when we only had to dodge the odd snotty patient, germ-ridden child and perhaps every now and then employ the skilful sleeve-over-the-hand technique on public bathroom doors.

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But since the outbreak of COVID-19, strict social distancing measures have been in place, with organisations such as the US Centers for Disease Control and Prevention recommending 2m of separation between people and the WHO recommending 1m.

However, these guidelines are based on a 90-year-old model of transmission that recent