Following on from his article about social distancing in the UK (Metric Views, 16 April), Ronnie Cohen now considers the contribution of the global measurement system to understanding the pandemic.
One thing that we take for granted when discussing social distancing in the UK and around the world is that the metre is a world standard with exactly the same definition across the globe. This is something we did not have until the metric system began to be widely adopted. This global standard enables an international organisation to make measurement-based recommendations that we can all understand in familiar units without any awkward conversions. For example, the World Health Organization (WHO) has recommended a minimum of one metre for social distancing to prevent the spread of coronavirus.
Recently, the Government has been considering a reduction in social distancing rules to 1.5 metres or 1 metre to bring the hospitality sector back to life. There has been pressure from MPs and from hospitality businesses to reduce or abolish the 2-metre rule for social distancing, and it has been said that most of these businesses would not be viable with this current restriction. This could lead to a large number of closures and job losses. It appears unlikely that there will be a reduction in the two-metre rule until July 2020.
For consideration of different social distancing options, it helps us to be able to compare social distancing rules with other countries in a common measurement system to learn lessons from them.
Reports from the BBC, news.com.au and the The Independent newspaper reveal the distancing rules in other countries:
- 1 metre: China, Denmark, France, Hong Kong, Lithuania, Singapore
- 1.4 metres: South Korea
- 1.5 metres: Australia, Belgium, Germany, Greece, Italy, Netherlands, Portugal
- 1.8 metres: US
- 2 metres: Canada, Spain, UK, New Zealand
The use of common and familiar units across the world helps international travellers to understand metre-based social distance signs in foreign countries. Imagine the situation we would have faced 200 years ago when countries (and even some cities) used local foot-based measurement systems. What issues would we face if other countries insisted on using their own national measurement systems?
There were many historical feet, now obsolete, that were once used in different cities and countries. The Wikipedia page on the unit of length called the foot (or local language equivalent) shows that the length of the foot varied from 272.8 millimetres in Zurich to 357.214 millimetres in Bordeaux. Compare these sizes to the 304.8 millimetres for the imperial (UK) foot. The table on that page lists 73 different feet and almost all of them varied in size from every other foot in the table. Some countries had different feet in different cities (e.g. 11 in Belgium, 21 in Germany, 9 in the Netherlands).
The use of different foot units in different countries would make international comparisons almost incomprehensible. The fact that we can debate social distance rules and make like-for-like comparisons with other countries is now taken for granted. It helps that we can learn from other countries’ experience of different social distancing rules (with other coronavirus rules), using common familiar units, to see how social distancing can be reduced from 2 metres.