London City Airport recently scrapped 100 ml liquid rule, which still applies in airports worldwide.

On 4 April 2023, London City Airport scrapped the 100 ml liquid rule. 1 Since 2006, airports worldwide have insisted that travellers can only bring liquids in containers of up to 100 ml in their carry-on bag. 2 These days, we take it for granted that the 100 ml limit for liquids at international airports around the world is exactly the same quantity. This is a triumph for the metric system, which replaced many different national systems long ago. Before the metric system, the same unit names were used for different quantities in different national measurement systems and there was no common definition for these units. The worldwide 100 ml liquid rule shows the benefits of a world standard measurement system for international travellers (i.e., the metric system).

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British contributions to the metric system

The development of the metric system was a truly international effort. The British have made substantial contributions to its development. The metric is in effect an English invention. Metrication was first proposed by an Englishman, the Reverend John Wilkins in 1668. British scientists have been at the forefront of developing the metric system, and many have given their names to metric units, including Newton, Faraday, Joule, Kelvin and Watt.

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Retirement of the US survey foot

It is well known that the USA uses miles, feet and inches and they are identical to the English versions of these units used in the UK. What is a lot less well known is the fact that the USA had two official feet, the international foot and the survey foot. By extension, there were also two versions of derived units based on these two feet. So there were survey and international versions of common units such as the mile, yard and inch. The US survey foot was deprecated at the end of last year. This deprecation act shows the importance of ensuring uniformity and common standards in measurement matters.

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Quirks of US Customary Units

Some would argue that the decline of manufacturing industry in the USA contributed to Mr Trump’s surprising victory in the Presidential election*. Others might say that manufacturing’s decline was due in part to the tardy adoption of the international system of measures. Here we look at some of the quirks of ‘English measures’, a throw back to the USA’s colonial past and still widely used in America today.

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The Worboys Committee Report revisited

Ronnie Cohen looks back at the 1963 Worboys Committee report and reviews how well the current version of the TSRGD addresses the main criticisms of the earlier traffic signs system and the Committee’s findings and recommendations. He suggests ways that current signage can be improved to meet the Worboys ideals.

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The reports of the death of the micron are greatly exaggerated

After a two month break, Metric Views returns with an article by UKMA’s new Chairman, John Frewen-Lord, about an aspect current metric usage. (With apologies to Mark Twain for the headline). Continue reading “The reports of the death of the micron are greatly exaggerated”