Now, I have a challenge for you.
I'm going to show you three images of roads in Adelaide.
I don't want you to tell me, if you do know, what the speed limit actually is.
What I'd like you to do is have a look at the road and assuming that you were the director
of the Department of Transport, what speed limit do you think you would apply to it?
So what speed limit ought to apply, not what the speed limit actually is.
So if we have a look at our first street, have a look at that street, and then there
will be some options.
When the clock appears, if you just kindly tell me what speed you think ought to apply
as a speed limit to this particular road.
We'll move on to another road.
What I'm asking is, what speed limit do you think ought to apply to this particular road?
There are a number of options, and the third environment is a fairly open road.
Again, the speed limit that you think should apply to that particular road.
I'd like to introduce my next speaker, which is Dr. Bruce Corbyn.
He's from Monash University, and he will run through a fourth myth for us that speed
limits are always safe speeds, and I'm sure they are because intelligent and articulate
men like you, Bruce, tell us what speed limits ought to be, and clearly they are the safe
speed limit, irrespective of the nature of the conditions and the nature of the road.
Let's have a look at some of the photographs we saw before the break, and see how you went.
So what sort of elements do we see in this photograph, please, Bruce, that might help
us understand what the speed limit ought to be?
So when we look at this road scene here, we see, for example, roadside poles, which are
particularly unforgiving, roadside trees as well, and I think that would be one of the
common concerns in that setting.
I think we know that even for cars with good safety features, collisions at about 50 kilometres
per hour is about the maximum impact speed that you would want for that type of crash.
It's a setting also in an urban area where we're likely to see pedestrians, bicyclists,
and again, we know in terms of the biomechanical limits of humans to impact forces that 30
kilometres per hour is about the maximum speed at impact that you would want to avoid
a particularly severe or a fatal outcome.
All right, well, perhaps we can move on to our second response.
Well, most people think it should be 50.
What do you think?
Well, again, I mean, the same sorts of issues arise there.
It's the potential for vehicles to collide with roadside objects.
We all think, I guess, that we're going to stay on the pavement, but one of the major
challenges, I guess, in Australia is people actually staying on the pavement and not finding
themselves in collisions with roadside objects.
So again, collisions over about 50 kilometres per hour start to produce pretty severe, very
severe outcomes.
If it happens to be a side impact, which quite often happens between a car and a roadside
object, maybe 30 kilometres per hour is about the maximum that your vehicle can withstand
before the risk of a severe outcome starts to rise rapidly.
Well then, if we moved on to the slightly more open roadway, it seems we've got a fairly
even spread in the middle there with a few drifting off to the 80 k's at the top end
there.
I'm just thinking there's probably about $400 each and some demerit points at that
end.
But what do we draw from this, please, Bruce?
Well, I think one of the major issues there, and certainly it is a wider road, and it does
tend to bring about a perception that higher speeds are OK, but we've got an intersection
right there in the sort of the mid-range of the photograph.
And again, thinking about the biomechanical limits of humans in crashes, collisions of
about 50 kilometres per hour is about the level that you don't want to exceed.
And in those circumstances, something like 1 out of 10 occupants or struck vehicles will
be at risk of a fatal outcome.
Above that 50 kilometres per hour, we start to get a very rapid rise in the risk of a
severe outcome.
And I see, off to the right-hand side of the picture, what looks like a bus shelter.
So have you done some analysis of these sorts of pedestrian collisions?
Yeah, we have, and they're all too common.
There's certainly problems, I know, in probably large parts of our country that we, our older
pedestrians are very much represented in the fatal outcomes, and we know that as people
age, their functional performance declines, they're not as agile, they're not as fast
in terms of crossing wide roads, and I think we need to start looking at the effects of
our ageing population in the future as well.
So have we looked at pedestrian fatalities and measured them perhaps in some way?
Do we have a graph on that sort of thing?
Yeah, look, we've had a, in Victoria, I think, if we can bring up a shot there.
This is a, I think, a very telling, simple trend, trend in pedestrian deaths going back
in 19, to 1980 in Victoria, all the way through to last year.
What we see is some distinct points there, I guess, where in the 1980s, we were averaging
something around 150 or so pedestrian deaths every year, then in 1990, that dropped to
a new level, below 100, and probably averaging around 80 or so deaths in that new period,
and the only feasible explanation for that was that speed cameras were introduced to
Victoria on a large scale in 1990.
In 2002, we see another step drop down, and again that happens to coincide, and that goes
from a level of around 60 or more fatalities each year, to a new level that ranges between
about 40 and 60, and that hasn't been exceeded, and again 2002 coincides with a major new
speed initiative with additional equipment, tighter tolerances by police, and a host of
other aspects focusing on speed.
Bruce, have you had the opportunity to have a look at things like the effect, for example,
that enforcement might have, or the effect that some of that awareness and education
might have, as opposed to some of the other factors, which limit the sort of speeds that
we travel at?
We certainly have had that opportunity, and over the last sort of five or six years, I
guess, the team that I work with at Monash University have been doing a lot of strategy
development work to help agencies and decision makers all around the country to estimate what
sorts of reductions in severe trauma, that is deaths and serious injuries, are possible
from investing in a whole range of road safety initiatives.
The next slide, I guess, is an illustration of the kinds of benefits.
On the vertical axis, you see there estimated reductions over a 10-year period in deaths
and serious injuries from, in the case of behaviour change programs, the blue bar, in
the case of safer vehicle initiatives, trying to accelerate the take-up of proven safety
features into the vehicle fleet, the yellow bar, investing in road infrastructure, the
red bar.
When we start to look at stepping up the effectiveness of our enforcement of existing
speed limits, the purple bar there, you can see an increasing result there, and if we
actually look at what might be possible from lowering speed limits, typically by 10 kilometres
per hour across the network, you can see the sorts of reductions that we get, and when
you actually look at those estimates and start to think about how much it costs to deliver
each of them, we find that reductions in speed limits, although politically difficult and
certainly controversial, can be done at an absolute fraction of the cost of the alternatives,
which might be about infrastructure investment, which also delivers well but is extraordinarily
costly to achieve.
All right, perhaps we might move open to some questions from the floor.
Yes, when I went to the Road Safety Council and I was learning to drive at Oakland's
Park, I might be 73 if I remember correctly, there was an emphasis on driving as fast as
you can versus as safely as you can.
Apparently, the local experiment was done to drive the length of Port Road at what was
then 35 miles an hour, so that would be what, a bit under 60, and a car going at 45 miles
an hour where they could, so I'd be getting what, 75 or so, and apparently the difference
going the whole length was only two minutes.
I don't think I've seen an emphasis in Road Safety which emphasises that going that much
faster doesn't get you there that much quicker, I was wondering whether more emphasis should
be put on that.
Look, we've done some research and it goes back about a decade now when Australia was
considering whether or not it would go from a 60 kilometre per hour default urban speed
limit to 50, which as we all know now has been done, and whilst we didn't have direct
evidence to measure the changes in travel time, simulation methods were used and the
impact of going from 60 to 50 was predicted to be something like a nine second increase
in your average urban journey as a result of that lower speed limit, and that most of
the influence on people's travel times is about congestion, about traffic signals, delays
of all sorts of other kinds, and a lot less about the actual speed limit.
Alright, I think we have another question up the top.
The previous graph that you showed which is the reduction in Victorian fatalities from
pedestrians showed a dramatic reduction in those fatalities in about 1990 after the introduction
of speed cameras.
I didn't see a very dramatic reduction in fatalities of pedestrians in about 2003 when
I believe the national urban speed limit was reduced from 60 to 50, but there was a slight
reduction there, I think for about 20% or something like that, would I be right there?
Look, the biggest gain I guess came in 1990 because speeds were so much higher in the network
at that time, so I think it makes sense to expect that with enforcement that you get
a substantial increase there.
The default urban speed limit I think was reduced in 2001 nationally, although I think
some states had actually begun sooner than that, so we do see again a sort of a marked
drop from around 2001, 2002, down to a substantially lower level from about 80 down to something
at that time, around 40 or so.
So I don't expect that the reduction would have been as great in the second opportunity.
And we have another question down here at the front.
I was wondering why roads only have one speed limit regardless of the conditions.
I just think I've driven in France where the auto routes have speed limits of 120 normally,
but clearly indicated if it's raining the speed limit is 90, and it's strictly enforced
because the conditions are different.
I know we don't have as much rain as France, but it would seem to me that it's not unreasonable
to have different speed limits according to the conditions.
Well, I think that we don't do that as you say.
I think there's a strong scientific argument I guess for doing that because if you go back
to the calculations that Rat talked about with stopping distances and we start to put
in a different level of friction on the road surface that exists on a wet surface compared
to a dry surface and maybe take account of the fact that vision ahead is reduced because
of poor atmospheric conditions, et cetera, then I think there's a strong rational argument
for something lower, but again we don't always behave rationally in respect of speed.
We do have some variable signs on the southeastern freeway as you descend from the Adelaide Hills
down onto the plains.
I think that's about the only place we have them.
Do we have another question somewhere else?
Yes, over the far side here.
Sorry, I just wondered whether there was any moves to work with car manufacturers around
car design because they're quite powerful nowadays.
I'm just, you know, something simple that was about increasing the pressure you have
to apply with your foot on your accelerator when you hit the speed limit for whatever
is set so that you've actually got that as a prompt.
It's a little bit different to a speed alert or a cruise control because if you're actually
watching the road, you're not necessarily watching your speed 100% of the time, but
just some way that this car is actually working with you rather than making it harder to stick
to the speed limit.
Look, I think there is, there certainly is some technology that's been around for some
years now and it's been trialled, it's been trialled successfully in Europe which is intelligent
speed assist and I think there's a number of attempts happening around the country to
try and get that sort of technology into more and more vehicles.
It's a GPS based system so that the vehicle knows in which speed limit you're driving
as long as the databases have been kept up to date and then you do get prompted if you
sort of are above the speed limit for two or three seconds and by a couple of kilometres
per hour you'll get a prompted either audible or visual or both signals in the vehicle and
in the more advanced forms you'll get upward pressure on the accelerator that makes it
very difficult for you to continue to drive above the speed limit.
It's possible in an emergency situation to be able to overtake but generally speaking
it's uncomfortable to keep working against that pressure to keep speeding.
So I think those sorts of technologies will continue to move throughout the vehicle system
over the years ahead.
Thank you and ladies and gentlemen thank you Bruce Corbyn.
