Parliamentary debate

The painfully slow progress made by the UK toward full adoption of the international metric system can be traced through over 200 years of parliamentary debate.

Throughout these debates the theme has been one of addressing problems caused by the failure to use a single rational system of weights and measures for all official purposes, and of the benefits and cost savings that result from switching to the metric system.

Weights and Measures
“… it was agreed, that the weights and measures should be the same in England and Scotland; but the uncertainty of the standard in England rendered it impossible to carry that article into effect. He would therefore move, “That a committee be appointed to enquire into the original standards of Weights and Measures in this kingdom, and to consider the laws relating thereto; and to report their observations thereupon, together with their opinion of the most effectual means for ascertaining and enforcing uniform and certain standards of Weights and Measures to be used for the future.””

Weights and Measures
“It would be recollected, that, two years ago, he had introduced a bill to establish the uniformity of weights and measures, which passed that House, but was lost in the House of Peers. A commission, it was then said, would be issued to the Royal Society, to determine what standard of weights and measures should be adopted.”
The First Report of the Commissioners appointed to consider more Uniform Weights and Measures was issued in 1819.

Weights And Measures (Metric System)
“… in short, nothing could be more confused than the present system. The adoption of the metric system would cure this want of uniformity, and would substitute for that which was inconvenient and difficult to learn a system which was simple and easy to be acquired. The adoption of this system would save half the time which was at present occupied in making calculations.
… a boy could make the same progress in arithmetic taught according to the metric system in ten months as would according to ​ the existing method take him two years and ten months to accomplish.”

Weights and Measures (Metric System)

Metric System of Weights and Measures

Standards Commission
“… The Royal Commission had recommended, among other matters, the voluntary use of the metric system, and, as a corollary, the abolition of Troy weight”

Elementary Education – The Metric System

Coinage – Decimal System
MR. ASHTON DILKE rose to move – “That, in the opinion of this House, the introduction of a Decimal System of Coinage, Weights, and Measures ought not to be longer delayed.”
“… Our scientific men had not used anything but the metrical system for the last 40 years; and the great accuracy now acquired in mechanical work, such as the casting of guns and the like, was only to be obtained by the use of the decimal system.
… Again, one of the most strenuous upholders of the decimal system, either as to value or as to weights, was the late Sir Rowland Hill, the author of the penny post reform. The actual saving of clerical labour which would attend the change would be very considerable.”

Use of Metric Weights and Measures in Trade
“… the use of a weight or measure of the metric system in trade shall be lawful”

Weights And Measures (Metric System)
“… While I look forward to the time, and no distant time, when they will adopt the change without difficulty and without repugnance, I should like to see private enterprise do more than it has done up to the present to show that the change can be adopted without inconvenience, and that it carries with it all the benefits which I, in common with you, firmly believe to be attached to the metric system, and which it is hopelessly impossible to associate with the arbitrary, perverse, and utterly irrational system under which we have all had the misfortune to be brought up.”

Decimal System
“… We cannot expect people whom we want to buy our goods to mess about working out our farthings, pence, shillings and pounds, and inches, feet and yards, when they can trade with many other countries on the metric system.”

Metric System

Metric System
Mr. Gresham Cooke asked the Chancellor of the Exchequer whether he will arrange for the Organisation and Methods Department of the Treasury to make an estimate of the savings which would be effected if the metric system were introduced for all Government work; and whether he will arrange for this to be done before a final decision is taken about the recommendations of the Hodgson Committee on weights and measures.
Mr. Simon No, Sir, this would involve disproportionate trouble and expense.”

Decimal Currency
“The noble Lord referred to the length of time occupied in teaching children the complicated calculation of pounds, shillings and pence. That is bad enough, but ounces, pounds, quarters and hundredweights are infinitely more laborious.”

Decimal Currency And Metric System

Weights and Measures
“… The Bill now defines the yard and the pound by reference to the metre and the kilogramme”

Weights and Measures (Metric System)
“… the Government consider it desirable that British industries on a broadening front should adopt metric units, sector by sector, until that system can become in time the primary system of weights and measures for the country as a whole.
… We shall also encourage the change to the metric system as and when this becomes practicable for particular industries, by seeking to arrange that tenders for procurement by the Government and other public authorities shall be in terms of metric specifications.
… the Government hope that within ten years the greater part of the country’s industry will have effected the change.”

Metric System
“The Construction Industry Training Board has a number of training aids in preparation and it will have a number of courses. This aspect will be covered. This industry will be in the vanguard of the change-over to the metric system, and it is assumed that the other industries will join the industry in this changeover. I am confident that the target date of 1975 will be accomplished.
… The changeover to the metric system offers a unique opportunity to introduce into the construction process the technique known as dimensional co-ordination, which will, if efficiently applied, greatly reduce the variety of components and fitments needed.”

“The Government accept the recommendation that a Metrication Board should be set up as soon as possible. Every sector of the economy need not move at the same pace. But there will be unnecessary confusion and expense, and great difficulties for industry, unless there is central machinery for co-ordinating the programmes of change for the various sectors.”

Metrication Board
“I have little doubt that the C.B.I. was right in saying that metrication and international standardisation of units were absolutely essential for this country’s future prosperity.”

Roads (Speed Limits)
“The Government have already decided that this country should move towards a metric system. We propose, subject to further consultation, that speed limits should become metric in 1973.”
The announcement that speed limits were going metric was widely reported in the following day’s newspapers.

Metrication of Weights and Measures
“The decision is inevitable. Speaking personally, I say not only is the process inevitable, but the sooner the better. To me it is a happy inevitability. If ever there were a non-Party political issue, this is it.”

“The present move towards metrication really dates from the publication of the Hodgson Committee’s Report – the Committee on Weights and Measures Legislation – in December 1950. The Hodgson Committee regarded the disappearance of the Imperial system as inevitable. It recommended the abolition of the Imperial system over a period of some 20 years, subject to a number of conditions, the majority of which have been fulfilled.”

“In support of these efforts, more than half the B.S.I. standards have now been expressed in metric terms: work continues and all new standards are of course metric from conception.”

“Some changes will have to take place all at once, but they will be very few. Perhaps the outstanding example is the road speed limits, about which I shall have more to say in a moment. Admittedly, gradualism has its dangers. Metric and imperial measures will have to co-exist for some time to come. What is important is that in each case the change to metric should be made with as short a transition period as is compatible with practical and economic considerations.
… the previous Administration exercised powers in 1969 under the Weights and Measures Act 1963 to abolish apothecaries’ weights and measures from January 1, 1971, so that trade in drugs will be wholly metricated from that date. The reason was, of course, that the continued use of two systems of weights and measures in dispensing could be dangerous. It is safer to use only one.
… Speed limit signs, if and when they are to be changed, must be changed at one go. The present Government are not committed to changing speed limits in 1973 as proposed by the last Administration. The Government have promised to review the question”

Roads (Speed Limits)
“… the Government have however decided that speed limits will not be made metric in 1973 and have no alternative date in mind.”



“A recent survey of engineering production showed that less than a fifth of firms are still working entirely in imperial units. The construction industry’s changeover programme is well on the way to completion. The change over to metric tariffs for overseas freight is the way to completion. The changeover of inland freight is well under way. The parcel and letter postal services will have metric charges in 1975.”



Sugar (Metrication)
“Metric packs of granulated sugar will start to appear in shops from now on and they should be generally on sale by the end of August, although imperial packs will not finally disappear until some time later. The new packs will have to be distinctively marked with the words METRIC PACK and to be marked in both metric and imperial. For example, the 1 kg pack will be marked 1 kg 2·2 lb. Industry also intends to mark packs with helpful information on metrication.”

Metrication Board

Weights And Measures



Metrication Board


Metrication: Government Policy

“… From 1 October 1995, almost all goods sold by quantity, including food pre-packed in variable weights such as cheese and meats that are not already traded in metric will have to be so traded. The principal exception is in respect of goods sold loose from bulk by the pound and ounce—primarily foods, such as meat, poultry, cheese, fish and fresh fruit and vegetables—which will not have to switch to metric until 1 January 2000”

Weights And Measures
“… in schools our children are taught wholly metric measures. The GCSE science syllabus is metric and all the details are in metric units. Even a measurement of force called “newton” – and no greater name exists in our history – is metric.
I wish to ask the Minister and other noble Lords who may be so committed what is the nostalgia for the lost Empire that makes everyone say that we must have imperial units? Even the so-called imperial units are not strictly British; we got them from somewhere else. The Minister said that the consumer bodies were not happy with the slow speed at which we are moving – and nor am I.
… why cannot his department come into the last part of the 20th century and prepare for the next century by going full steam ahead in the metric direction?”

“A defence standard prescribing the metric units to be used by the Ministry of Defence, including the services, was developed and published in 1976.”

Weights and Measures
“… Metrication was introduced into our schools by the noble Baroness, Lady Thatcher.
… Every other country in the world has gone metric. Every Commonwealth country has completed metrication.
… These changeovers sometimes cause a fuss. It would have been much easier if we had kept the Metrication Board.
… It is a pity that the Decimalisation Board, which did a great job, was not followed in due course by the Metrication Board, which, as the noble and learned Lord, Lord Howe, explained, was abolished, I think by him, as one of the first acts of the new government. He rather regrets that it was done. The Decimalisation Board was a great success. If the Metrication Board had been, the fuss might be somewhat limited.”

NHS: Metric Units
Lord Howe: “Is the Minister aware that on 7 December 2008 her noble colleague, the noble Lord, Lord Drayson, when he was the Minister of science, wrote to the chairman of the UK Metric Association as follows:
“The Government’s longstanding policy – is to move towards full metrication in time – We recognise that a single system of units of measurement as a reference point is vital for fair trade and consumer protection”?
Is she further aware that since I was concerned with this topic decades ago, almost every country in the British Commonwealth – including the Republic of Ireland – has completed that process absolutely fully? Is it not time for all of us, in all parties – I come to the crucial point – now to work together to clear up this long-standing and very British mess?”

Education: Proficiency Levels

Consumer Rights Bill

Consumer Rights Bill


Weights and Measures Act 1985 (Definitions of “Metre” and “Kilogram”) (Amendment) Order 2020

Lord Rennard: “My Lords, the early 1970s saw a series of changes that I began learning about while at primary school. At that time, many people were confused about how the country was taking steps towards the adoption of metric measurement, decimalisation of the currency and membership of what was then generally still known as the Common Market. There was little awareness in this country about the history ​of the metric system being adopted in many other countries as older systems, some of them based on units set in Roman times, were replaced.
It was not appreciated by everyone in the UK at the time that we remained free to sell pints of beer, use road signs based on yards and speed limits set in miles. Governments did little to persuade people that metrication was not being forced upon us in the way that the noble Lord, Lord Foulkes, described French revolutionaries and the Emperor Napoleon doing some two centuries ago. This failure accounts for some of the prejudice against metric systems, even though they have been central to arrangements that allow countries to trade successfully with each other.
As my noble friend Lady Northover said, they have had an important role in public safety as well as protecting consumer interests. International standards are generally a good thing, which is why this order makes sense. The principle of international standardisation was recognised in the Weights and Measures Act 1824, but that applied only to the British Empire as we sought to impose the standard imperial system of weights and measures upon it. Parliamentary Select Committees throughout the 19th century kept recommending the general adoption of metric systems, only for progress to be blocked for fear of a public backlash.
Meanwhile, British scientists were at the forefront of the metrication movement. It was the British Association for the Advancement of Science that promoted the centimetre, gram, second system of units as a coherent method of measurement. It was the British firm Johnson Matthey that was accepted by the General Conference on Weights and Measures in 1889 to cast the international prototype metre and kilogram, although it was not until 1965 that the UK began an official programme of metrication. We have dragged our feet or, I should say, our 30 centimetres on this. Perhaps the Minister could enlighten us on progress on metrication generally, given the importance of international standards to trade.”

Lord Wei: “In fact, it is true to say that Britain and British scientists and thinkers have played a key role in developing the metric system, with the likes of Kelvin and, more recently, Kibble, who developed some of the techniques that have led to the current definitions that we are discussing today.”

Lord Blencathra: “Will I have to return my tape measure to B&Q since the metre scale no longer corresponds to 1.09361 yards? Will the Minister tell us what practical differences these changes will make?
In conclusion, I would prefer my noble friend to tackle the law-breaking by many councils which are illegally introducing metric measures on road signs. The law is absolutely clear: metric units are not permitted on distance signs, whether by themselves or in conjunction with imperial units. Distances must be in miles and yards only, and that applies to all traffic signs, not just those for motorists. Yet there are countless examples of councils erecting illegal signs in metric units. Will my noble friend therefore take up this matter urgently with the Department for Transport to make sure that all councils obey the law of this country and not what they might wish it to be?”