50 years of metric road signs in Australia

[Glenn A]

Coming up 50 years or so since Australia's drive to metrication( pun intended) saw all road signs, speedometers and speed limits switched to metric measurements in 1974/75. I know from being WA 28 years ago, the speed limit on freeways is 120 km/h and on other non urban roads it can be 100-110 km/h depending on road conditions. I was wondering before the switch to metric measurements, what the speed limits in mph would have been on Australian roads and prior to the energy crisis, if freeways were unrestricted.

[exiled]

Famously you have the ad here and this from Channel 7 Queensland. The ad suggests the rural limit of 60 mph went to 100 km/h rather than being deristricted. But it depended of course on the state or territory.

Looking up, NZ switched at the same time and had an oil crisis limit of 50 mph that became 80 km/h on metrication.

[Glenn A]

Famously you have the ad here and this from Channel 7 Queensland. The ad suggests the rural limit of 60 mph went to 100 km/h rather than being deristricted. But it depended of course on the state or territory.

Looking up, NZ switched at the same time and had an oil crisis limit of 50 mph that became 80 km/h on metrication.

So the speed limit was 2 mph faster when it was metricated, but more logical being rounded up to 100 km/h that the signs saying 96 km/h. Interesting how quickly and painlessly the transformation was made, but the ad does mention older cars with mph only speedometers that might have been confusing for some people.

[exiled]

Famously you have the ad here and this from Channel 7 Queensland. The ad suggests the rural limit of 60 mph went to 100 km/h rather than being deristricted. But it depended of course on the state or territory.

Looking up, NZ switched at the same time and had an oil crisis limit of 50 mph that became 80 km/h on metrication.

So the speed limit was 2 mph faster when it was metricated, but more logical being rounded up to 100 km/h that the signs saying 96 km/h. Interesting how quickly and painlessly the transformation was made, but the ad does mention older cars with mph only speedometers that might have been confusing for some people.

Ireland of course rounded when it metricated, as there are few points where there is a direct match. 30 mph is 48 km/h so 50 makes sense. 60 is 96 so the choice is 90 or 100. Generally this has been to 100 km/h. The UK has a limit of 70 mph which is 112, so on a DC this could become 110, with the opportunity to make some rural m'ways into 120 or even 130 km/h.

[FosseWay]

... but the ad does mention older cars with mph only speedometers that might have been confusing for some people.

Is there any information on whether this kind of thing actually affects people's safety on the roads?

My car, in common with pretty much all other cars in the EU, has km/h only on the speedo. I don't have a problem obeying UK speed limits when I drive it in the UK. And my car is older than average, certainly older than average for the kind of distances I drive on holiday. Modern cars have digital displays that can be changed to display the relevant unit.

I get the feeling that the authorities overegg certain issues, like this one. They did it as well with the currency, both in 1971 in the UK and in 2002 in the eurozone. In both cases there was a generous changeover period that in practice wasn't really used, as people adapted to the new currency very quickly.

[Truvelo]

I've hired some cars in America which have just a single row of numbers on the speedo. When switching between miles and km the needle would say jump from 30 to 50 and the light below it changes from mph to kph. I think it's a neat idea. Of course, digital cockpit displays are gradually rendering it obsolete.

[exiled]

I get the feeling that the authorities overegg certain issues, like this one. They did it as well with the currency, both in 1971 in the UK and in 2002 in the eurozone. In both cases there was a generous changeover period that in practice wasn't really used, as people adapted to the new currency very quickly.

I think it is less over egging it, but more a case of making sure as much as possible that the info is gotten out.

[freebrickproductions]

I've hired some cars in America which have just a single row of numbers on the speedo. When switching between miles and km the needle would say jump from 30 to 50 and the light below it changes from mph to kph. I think it's a neat idea. Of course, digital cockpit displays are gradually rendering it obsolete.

My car, a 2012 Mazda CX-9, has both mph and km/h marked out on the speedometer as well. The larger, primary, numbers/markers are mph while the smaller markings and numbers are km/h.

As a side note, my signage collection features a couple of old metric German speed limit signs, that I found earlier this year at an antique store just outside of Cullman, AL.

[Isleworth1961]

My car, a 2012 Mazda CX-9, has both mph and km/h marked out on the speedometer as well. The larger, primary, numbers/markers are mph while the smaller markings and numbers are km/h.

That's been the norm for decades before switchable digital displays.

[freebrickproductions]

My car, a 2012 Mazda CX-9, has both mph and km/h marked out on the speedometer as well. The larger, primary, numbers/markers are mph while the smaller markings and numbers are km/h.

That's been the norm for decades before switchable digital displays.

I'm not too surprised about that, IIRC the 2004 Toyota Sienna's speedometer was the same way. I do have to wonder which is cheaper to maintain and produce, I'd imagine the ones that have both units displayed would be though.

[aj444]

For some reason bus speedometers traditionally have KM's and Miles, sometimes the KM's in bigger numbers than the miles. Cue Grandma sitting on an ancient Seddon Pennine 7, ringing in to complain "he was doing 100, I could see it on his speedometer"

[Glenn A]

For some reason bus speedometers traditionally have KM's and Miles, sometimes the KM's in bigger numbers than the miles. Cue Grandma sitting on an ancient Seddon Pennine 7, ringing in to complain "he was doing 100, I could see it on his speedometer"

For motor coaches, the tachograph works in metric units, but the speedometer has to show mph as well due to road signs being in imperial units. Same with HGVs, where mph is displayed in smaller numbers.

[Truvelo]

For some reason bus speedometers traditionally have KM's and Miles, sometimes the KM's in bigger numbers than the miles. Cue Grandma sitting on an ancient Seddon Pennine 7, ringing in to complain "he was doing 100, I could see it on his speedometer"

For motor coaches, the tachograph works in metric units, but the speedometer has to show mph as well due to road signs being in imperial units. Same with HGVs, where mph is displayed in smaller numbers.

And the speedos on these vehicles are dead accurate too due to the tacho. No overreading by up to 10% as found on cars and vans.

[Glenn A]

For some reason bus speedometers traditionally have KM's and Miles, sometimes the KM's in bigger numbers than the miles. Cue Grandma sitting on an ancient Seddon Pennine 7, ringing in to complain "he was doing 100, I could see it on his speedometer"

For motor coaches, the tachograph works in metric units, but the speedometer has to show mph as well due to road signs being in imperial units. Same with HGVs, where mph is displayed in smaller numbers.

And the speedos on these vehicles are dead accurate too due to the tacho. No overreading by up to 10% as found on cars and vans.

Interesting about speedometers being inaccurate as I was driving into Moffat yesterday, and the Your Speed digital sign clocked me at 28 mph, when the speedo was on the 30 marker.

[doebag]

For motor coaches, the tachograph works in metric units, but the speedometer has to show mph as well due to road signs being in imperial units. Same with HGVs, where mph is displayed in smaller numbers.

And the speedos on these vehicles are dead accurate too due to the tacho. No overreading by up to 10% as found on cars and vans.

Interesting about speedometers being inaccurate as I was driving into Moffat yesterday, and the Your Speed digital sign clocked me at 28 mph, when the speedo was on the 30 marker.

My motorcycle over reads by 2mph at any speed up to 80mph. An indicated 32mph is a satnav 30, and road side signs always show me as doing 30mph.

[aj444]

For some reason bus speedometers traditionally have KM's and Miles, sometimes the KM's in bigger numbers than the miles. Cue Grandma sitting on an ancient Seddon Pennine 7, ringing in to complain "he was doing 100, I could see it on his speedometer"

For motor coaches, the tachograph works in metric units, but the speedometer has to show mph as well due to road signs being in imperial units. Same with HGVs, where mph is displayed in smaller numbers.

And the speedos on these vehicles are dead accurate too due to the tacho. No overreading by up to 10% as found on cars and vans.

Not so for service buses in the UK. No tachographs required unless the route is over 50km.

[Vierwielen]

Famously you have the ad here and this from Channel 7 Queensland. The ad suggests the rural limit of 60 mph went to 100 km/h rather than being deristricted. But it depended of course on the state or territory.

Looking up, NZ switched at the same time and had an oil crisis limit of 50 mph that became 80 km/h on metrication.

South Africa changed to km/h about a year before the oil crisis. During the crisis, a 50 km/h urban and 80 km/h rural speed limits were introduced with draconian fines - in todays terms, the equivalent of £500 to £1000 before you asked how fast you were going. The figures of 32 mph and 51 mph are still entrenched in my mind.

[Vierwielen]

I've hired some cars in America which have just a single row of numbers on the speedo. When switching between miles and km the needle would say jump from 30 to 50 and the light below it changes from mph to kph. I think it's a neat idea. Of course, digital cockpit displays are gradually rendering it obsolete.

In my view, having the needle jump from 30 [mph] to 50 [km/h] with the display background remaining unchanged apart from a light which shows whether it it mph or km/h is not a good idea. It woudlo be far better to have the background display change and th eneedle to remain fixed, thus if the needle is horizontal when it shows 30 mh it would remain horizontal when it shows 50 km/h. Using modern technolgy this could easily be implemented using LCD (or similar) technology. This is the concept used by the UK variant of ETCS when switching between legacy lines and lines under ETCS control.

[Glenn A]

Famously you have the ad here and this from Channel 7 Queensland. The ad suggests the rural limit of 60 mph went to 100 km/h rather than being deristricted. But it depended of course on the state or territory.

Looking up, NZ switched at the same time and had an oil crisis limit of 50 mph that became 80 km/h on metrication.

South Africa changed to km/h about a year before the oil crisis. During the crisis, a 50 km/h urban and 80 km/h rural speed limits were introduced with draconian fines - in todays terms, the equivalent of £500 to £1000 before you asked how fast you were going. The figures of 32 mph and 51 mph are still entrenched in my mind.

Didn't South Africa introduce a speed limit equivalent to 45 mph during the 1979 energry crisis, which must have been real fun as South Africans liked big cars?

[Vierwielen]

Famously you have the ad here and this from Channel 7 Queensland. The ad suggests the rural limit of 60 mph went to 100 km/h rather than being deristricted. But it depended of course on the state or territory.

Looking up, NZ switched at the same time and had an oil crisis limit of 50 mph that became 80 km/h on metrication.

South Africa changed to km/h about a year before the oil crisis. During the crisis, a 50 km/h urban and 80 km/h rural speed limits were introduced with draconian fines - in todays terms, the equivalent of £500 to £1000 before you asked how fast you were going. The figures of 32 mph and 51 mph are still entrenched in my mind.

Didn't South Africa introduce a speed limit equivalent to 45 mph during the 1979 energry crisis, which must have been real fun as South Africans liked big cars?

I don't know about 1979 as I was living in the UK by then. However, at the time of the Yom Kippur War (1973), an 80 km/h speed limit was introduced with about two days notice. Some friends of mine had been on a one-week safari in Botswana when the announcement was made and on their return, wondered why everybody was driving so slowly.

The other crunch was that petrol stations were shut from 17:00 to 08:00 and did not open at all on Satudays or Sundays. AS it was not possible to drive from Johannesburg to Durban (600 km) on a single tank that cut out a lot of social driving. People who had to drive any distance over the weekends (eg taxi drivers, also the Bishops who might have to visit distant churches) were permitted to hold a certain amount of petrol in safe containers. There was of course a black market - at one wedding that I went to, friends of the host quietly asked each guest if they could borrow the guest's car keys for a few minutes. Miraculouly some petrol appeared in the guest's petrol tank!

When I left South Africa in Febrary 1978, I had my car shipped over to the UK. I drove from Johannesburg to Durban overnight with a jerry-can of petrol in my boot. When I was at a particularly deserted part of the journey (about half-way), I topped up my tank and discarded the jerry can (which probably found a good home somewhere in the Orange Free State).