In other Anglophone countries such as Australia, Singapore and New Zealand, imperial units have been formally deprecated and are no longer officially sanctioned for use.
[3] Early measures were human in scale, intuitive, and imprecise, as illustrated by still-current expressions such as a stone's throw, within earshot, a cartload or a handful.
[4] Nowadays most non-metric units are standardised to fixed values, which eliminates the disadvantage of imprecision while retaining the advantage of human scale.
[5] Metric opponents cite easier division of customary units as one reason not to adopt a decimalised system.
[citation needed] The main disadvantage cited by critics of customary measures is the proliferation of units, their (sometimes) non-unique definition and the difficulty in remembering the ratios between them.
[citation needed] A common argument for the metric system is that it avoids duplication of naming and the associated confusion.
As the table below shows, industries have addressed such concerns by using a "hard conversion" into metric units of the dimensions involved.
One example of this is paper sizes: the widely used A series specification begins from A0, which has a surface area of 1 square metre, with sides in the ratio of approximately 1:√2 (841mm by 1189mm).
In addition, a reference standard (a rod of platinum-iridium alloy) is maintained by the inter-governmental organisation the International Bureau of Weights and Measures, and calibration of a standard metre is usually achieved (to one part in a billion, or slightly better in some recent installations) by counting 1,579,800.298728 wavelengths of the ultra-fine (3s2 to 2p4) emission line of helium–neon laser light (this wavelength being approximately 632.99139822 nm in a vacuum).
On 8 May 2007, several British newspapers including The Times[11] used correspondence between Giles Chichester MEP and EU Commissioner Günter Verheugen to report that the European Commission had decided to allow meat, fish, fruit and vegetables to continue to be sold in pounds and ounces.
On 29 March 2010, NASA decided to avoid making its proposed Constellation rocket system metric-compliant, especially due to pressure from manufacturers; ultimately the program was discontinued.
It had been predicted that it would cost US$368 million to convert to metric measurements for parts made by both NASA and external companies.
[17] Despite NASA's non-compulsory policy, commercial space manufacturer SpaceX currently designs its systems (e.g., Dragon and Falcon 9) using metric units.
"[19] In his 1998 monograph Seeing Like a State: How Certain Schemes to Improve the Human Condition Have Failed, James C. Scott argued that central governments attempt to impose what he calls "legibility" on their subjects.
Scott cites the enforcement of the metric system as a specific example of this sort of failed and resented "improvement" imposed by centralizing and standardizing authority.
[20] While the metric system was introduced in the French law by the revolutionary government in April 1795,[21] it did not immediately displace traditional measurements in the popular mind.
In fact, its use was initially associated with officialdom and elitism as François-René remarked in 1828: "Whenever you meet a fellow who, instead of talking arpents, toises, and pieds, refers to hectares, metres, and centimetres, rest assured, the man is a prefect.
[26] The current British Weights and Measures Association, or BWMA, is an advocacy group established in the United Kingdom in 1995, founded by Vivian Linacre.
The BWMA's campaign parallels the evolution of the eurosceptic viewpoint of the UK's relationship with the EU[28] - its founder, Vivian Linacre, stood for election as a UK Independence Party candidate in 1995, the same year as he founded the BWMA - famously asking the controversial eurosceptic Enoch Powell for endorsement of his political campaign.