Recently, one of our readers wrote to his MP about the UK’s measurement muddle. He received a reply from the office of the Minister for Universities and Science, David Willetts MP, who has responsibility for measurement standards in the UK. This reply confirms that the Government has no plan to reduce the current mixture of units in common use in the UK or to promote a single system of measurement for all purposes.
Since the start of the UK’s metric changeover in the 1960s, the Government has always maintained that one day we will become a metric country. We now learn that this target has been put off to an indefinite time in the future, or perhaps never.
This is the reply to our reader’s MP from David Willetts MP:
“22 May 2014
UK Measurement System
Thank you for letter of 7 May 2014, concerning an enquiry from your constituent, about the UK measurement system.
The UK is already substantially metric. The only authorised usages of imperial units as primary indications are those referred to in your letter – the mile, yard, foot, and inch for road traffic speed, signage and distance measurement and the pint for draught beer or cider and doorstep milk – together with the troy ounce for the sale of precious metals. Imperial units also may be used alongside metric units in dual labelling.
The Government supports a single system of units of measurement in principle, but recognises that many people in the UK prefer or are more familiar with imperial units. Therefore, the Government is committed to retaining the existing usages of imperial units for as long as consumers and businesses find it useful.
Road traffic speed and signage are matters for the Department for Transport. However, I understand that they have previously estimated that a change to metric would cost in the region of £700 million.
The Government has no plans for further metrication to end the few remaining primary uses of imperial units or to end their use in dual labelling. There is no significant demand from business or consumers for such change and the costs are likely to far outweigh any benefits.
I hope your constituent finds this information useful.”
Mr Willetts repeats the DfT estimate for changing speed limit and distance signs of about £1200 per sign, when recent research has shown this figure to be closer to £120 per sign. One can only suggest that if the case for retaining imperial road signs were stronger, the Government would not have to rely on this dubious estimate.
Even Mr Willetts is unable to resolve the conflict between the Government’s support for a single system of units of measurement and the DfT’s resolute opposition to metric speed and distance signs, resulting in the continued existence of about half a million imperial-only signs on UK roads. Consumers will, of course, find inches, feet, yards and miles on road signs useful when there is no alternative. But they may then prefer these pervasive, and consequently familiar, units in usages where there is a choice. And so the muddle continues.
Leaving this nonsense aside, what does this hybrid collection of measures advocated by Mr Willetts and adopted by default by the Government look like?
Here are some of the measures readers may have encountered recently on the street, in the media or at home:
Length millimetre, inch, foot, yard, metre, kilometre, mile
Area square foot, square metre, acre
Volume millilitre, pint, litre, imperial gallon (for mpg), cubic yard, cubic metre
Mass gram, pound, kilogram, stone, tonne
Pressure millibar, pounds per square inch, bar
Temperature °C, °F
Power watt, kilowatt, BTU per hour
Energy joule and kJ, calorie and kcal, kilowatt hour, therm
“Fine” says Mr Willetts. “Apart from road signs, let business or consumers decide. Let them demand changes if they want them.” An easy option for him and his colleagues – put off the difficult decisions, and hope the problems will go way.
But how does, for example, a child learning numbers and measurement at school select which unit to use when there is such a bewildering choice?
A recent publication¹ deals with the impact on maths education of the “few remaining primary uses of imperial units” and the measurement muddle that results from them. Metric Views will be returning in the future to the subject of education.
¹ “How big is an acre? No one knows.” Written and published by Alan Young in May 2014, and available from www.drmetric.com.