The Case for Social Distancing

Around the World, governments are advocating social distancing. Companies such as ourselves are offering tech-based solutions to warn about close contacts, as they happen. However, what is a safe distance?

Governments seem to recommend arbitrary distances, for example, China (1m), France (1m), Singapore (1m) through Australia (1.5m), Germany (1.5m), Greece (1.5m), Netherlands (1.5m) up to the United Kingdom (2m), Spain (2m) and Canada (2m). Countries are providing inconsistent guidelines. What do the various distances actually imply in terms of reducing the risk?

The Lancet has just published a paper Physical distancing, face masks, and eye protection to prevent person-to-person transmission of SARS-CoV-2 and COVID-19: a systematic review and meta-analysis that’s effectively research on research. It provides a summary of 172 observational studies across 16 countries and six continents on common respiratory viruses.

The risk of being infected is estimated to be 13% at less than 1m. Every extra metre of distance reduces the risk by half. 1m provides for a large reduction in infection but 2m is a much safer distance. 1.5m is a pragmatic option especially if other factors can be combined such as limiting the length of exposure, using of face protection or other contextual considerations. Neither distance, reducing length of exposure nor face masks provide complete protection from infection.

For tech based solutions it’s important to be able to fine tune the distance to governments’ advice and contextual considerations. It’s also important to be able to measure the length of exposure and filter out exposures that are so short as to pose negligible risk.

Read about Distance Bands for Workplace Social Distancing and Contact Tracing