By 1 January 2008, speed limiters will have been fitted to all recently registered, and many older, buses, coaches and goods vehicles over 3.5 tonnes.
All speed limiter settings are specified in kilometres per hour.
For certain classes of vehicle, the maximum speed limit on motorways, as shown in the Highway Code, is now significantly greater than the maximum legal speed permitted by these vehicles’ speed limiters.
This anomaly is acknowledged by VOSA (Vehicle and Operator Services Agency) in their leaflet “New Speed Limiter Legislation” which states:
“It is likely, once all the changes to vehicles requiring road speed limiters have taken place (after 1 January 2008), the national motorway speed limit for goods vehicles over 3.5 tonnes and buses will be lowered.”
Currently, 70 mph is the maximum speed limit on motorways for goods vehicles not exceeding 7.5 tonnes maximum laden weight, and 70 mph is the limit for buses and coaches.
Will these speed limits be brought into line with speed limiter settings? i.e. 90 km/h (56 mph) and 100 km/h (62 mph). Will they be set at 55 mph and 60 mph? Or will they be set at some other values?
When defining speed limits, why not remove the anomalies that arise from using two incompatible systems, and set all national speed limits in kilometres per hour instead?
Metric Views 
The Department for Transport could find themselves in real trouble over this. It would appear that although there is a commitment to fit the speed limiters by 2008-01-01 (only 9 months away) they have no solution to these anomalies.
If they don’t resolve it by then, drivers of older vehicles (not requiring the limiters) will be laughing all the way to the bank!
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The really crazy part of this regulation is that in certain circumstances speed limiters will not be required within the United Kingdom, but will be required elsewhere within the EU. In such cases the label on the back of the vehicle be in mph, but the rule of the road concerned will be in km/h.
BTW, the first reference in Martin’s posting give speeds in “kph”, not “km/h”.
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The issue of speed limits reminds to ask if the UK is the only country in the world that legally forbids the posting of metric distances and speed limits.
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In answer to Ezra’s question, the UK doesn’t actually “legally forbid” metres and km on distance signs. Private signs can display any unit they like as long as they obtain appropriate permission under the Control of Advertisement regulations for the size and location of the sign (the content is not controlled). However, it is true that the Traffic Signs Regulations only authorise imperial units on official signs showing distance and speed limits. Signs showing heights and width restrictions can be in both metres and feet and inches. It is, of course, a mess.
I cannot be certain that there is no other backwater in the world that forbids metric traffic signs but I don’t know of any. Certainly, the USA permits both metric and imperial (on separate signs) – albeit metric signs are rare.
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This really is an awful mess. We already see plenty of (foreign) vehicles driving on UK roads with “90” and “100” stickers, and have done for years, and I’m pretty sure everybody knows what they mean: it’s pretty obvious that they can’t be mph! And I’m sure British lorry and coach drivers who drive abroad will be quite used to the system by now, so why confuse things by changing the standard stickers from km/h to mph? Either km/h stickers should be approved for British vehicles, or the default km/h stickers should have a small ‘km’ subtitle (like Irish speed limit signs) and smaller ‘mi’ stickers, of a clearly different design, placed underneath if absolutely required.
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The real problem here is that while the myth that “more people understand miles” continues nothing is ever going to happen. I did some rough estimates based on the 2001 census – make the assumption that most people likely to be driving now were between 10 and 64, anybody under the age of 35 would be metric educated and from 35 to 45 would have been partly metric educated, only 33% of those currently likely to be using our roads would not have had any metric education, meaning that 67% have.
Add to this the number of Brits travelling abroad to metric countries who may have driven (particularly the “tabloid-booze-cruisers”) and the growing number of non-British drivers on uk roads, surely it’s time this myth was blown right open.
Unfortunatly, the biggest problem is that the metric-educated 67% from above walk out of school every night onto our “imperial” roads and so much of what they learned goes to waste. No wonder our kids are mixed up!
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Alex,
I think your estimates of metric education are on the low side. I am 43 and I remember having kg weights in our classroom at primary school. I don’t remember ever learning any imperial measures at school, and I still don’t know how many yards there are in a mile. I understand that even before Britain went metric in 1965, the metric system was widely taught at school. Even those who didn’t learn at school can’t fail to have picked up some knowledge of metric since leaving. I don’t think there is a single driver on the British roads who couldn’t cope with m and km. It’s time to stop letting them get away with that excuse.
The only reason not to go metric on our roads is the cost. And since it’s only going to get more expensive the longer we wait, the best thing would be to get on with it now.
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Dave,
Thanks for the correction. I have been working on the basis that the cut-off date where metric education started was 1974… I am 39 myself and also do not recall receiving any imperial education of any kind either and to this day still can not remember how many lb in a stone or feet in a mile without looking it up! In being wrong it is only more clear that the excuse about the British public not understanding metric is considerably more flawed.
The cost of converting roads to metric is often quoted as an excuse to not convert, but I’ve yet to see any figures showing how much it is actually costing this country to not convert. Perhaps if the “man on the street” knew how much money was being spent by industry on dual- or market-specific labeling, the cost of producing special “mph” speedos for British cars and the wastage caused by mistakes in unit-conversion (amongst other things!) so that this could be compared against the actual conversion costs, government ministers might find it a little harder to justify keeping things as they are. The current position seems to be that they will find any excuse to retain the existing derrogations!
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Metric education must have started earlier as I am 46 and was never taught imperial units. All our rulers were calibrated in cm and mm plus we had the metre rule which the Headmaster used to punish pupils!
By the way, has anyone noticed the ridiculous stickers on some UK vehicles stating: This vehicle is limited to 52 mph OR 56 mph. They are absurd. Even many UK school buses/coaches have 100 on the back window!
This is a farce and it really is no wonder that people are not able to measure or weigh accurately.
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Hi PhilipII
The final cut off for imperial measurements in education was 1973, ie metric only from 1974 onwards. However many education authorities phased it in sooner, from about 1968. I know that in my case, starting school in 1972, I was never ever educated in imperia throughout my 13 years in education – thank goodness 🙂
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