50km/h local speed limit

The Queensland Government has recently introduced a general 50km/h urban speed limit for the South East Queensland area. This has been acompanied by a saturation advertising campaign carefully worded so as to convince the general public that this has been a carefully thought out plan to save (huge numbers of) lives on the road.

The television advertisements feature two shots of a car in a full lockup emergency stop. One view the (50k/hr) car narrowly stops before cleaning up a child that has just run on the road. The we see an overlaid view of the same car (now doing 60km/h) and of course going well past the child. The tagline states that it will take 12 to 16 metres more to stop from 60k vs. 50k
 

Speed: Is it the big problem we are told?

The following is an analysis of the state of Traffic law in the State of Queensland with particular emphasis on Speed and Speeding.
Are we are being hoodwinked into accepting 50km/hr, speed cameras, getting fined for it and STILL feeling guilty about it? Read the following and make your own judgement.
 
 

Speed and its effect on Braking Distance

Much has been made of the effect of “the extra 10 km/hr” regarding braking distances in several intensive media campaigns designed to soften the public up and implant the idea that speeding is perhaps the most serious offence one can commit on the roads. Unfortunately, the entire campaign is based on gross exaggerations and lies.
In the latest campaign, aimed at justifying the introduction of 50km/h speed limit in South East Queensland, we’ve even seen an exaggeration of an exaggeration. The official Queensland Government road-safety brochures (and web site [ref 1]) show a graph that lists the following:

 

Speed  km/h	Reaction  Distance	Braking Distance	Total
50	10	15	25
60	13	22	34
70	15	28	43
80	17	37	54
90	19	47	66
100	20	60	80

The reaction time is based on a very slow witted person taking three quarters of a second to react. Most people will record a reaction time between one and two tenths of a second, not 0.75 as stated in official explanation.

Note that even the inflated official graph shows only 9 metres more (60 vs. 50) yet on the TV adverts they say 12 to 16 metres!!! It’s nothing more that blatant lies and propaganda, but wait it gets better. Almost any car can completely stop in from 60 km/h in about 17 metres [ref 2]. (a typical car can do it in about 15.5 metres, and a good one can do it in 13.5m)

If you would like to confirm the above, it’s easy. Pick up any copy of the American published ROAD and TRACK magazine – available from virtually any newsagent. The magazine lists tested braking distances for about 120 different cars stopping from 60mph and 80mph in a section called “Road Test Summary”.

Now compare the tested braking distances for 60mph (96km/h) with the 60 metres (197ft) quoted by the good old transport department. Most cars fall between 130 and 150 ft which means the official figures are inflated by 30% or more for a start.

The Braking distances for any other distance can be calculated by using the square of the two speeds as a ratio. This is because braking distance is a function of kinetic energy dissipated, and kinetic energy is proportional to the square of the velocity.

So if we want to calculate the braking distance at 60km/h we can use the  ‘typical poor car’ distance 145ft from 60mph – or 44.2 metres from 96km/h

(Note: 90% of the cars listed stop in a shorter distance, with a Ferrari 550 Marranello capable of doing it in only 112ft (34.13m))

Calculating the ratio: 60 squared, divided by 96 squared, is 0.391. Multiply this by the 96km/h braking distance and we get:

    0.391 x 44.2 = 17.28 metres.

Remember this is from 60km/h to a complete stop

Applying the same principles we calculate 11.99 metres for a 50km/h stop, a difference of only 5.29 metres. This is a far cry from the 12 to 16 quoted in the TV advertisements but it is an example of just how far the authorities will go, in order to brainwash us all into believing their little moneymaking scheme will be good for all of us.

But won’t a lot of pedestrian lives be saved?

Well we all KNOW that “50km/h on local streets will save lives” – they’ve been indoctrinating us that for months! But where is the research that backs this up, and perhaps more importantly, just how many lives can we expect will be saved? I doubt anyone in the transport department has even bothered to do an estimate since it is all rhetoric and propaganda.

Officially, only "up to 30% of casualty crashes occur on local streets" [ref 3]
Unfortunately, the published Queensland statistics do not give any breakdown that would allow this statement to be confirmed, and given their record so far it is entirely likely that this too is a fabrication.  A recent study performed in Adelaide [ref 4] (although not a really shining example of road safety research) which states that only 14% of severe casualty accidents occur on local streets adds weight to these suspicions.

What we do know is that the total PEDESTRIAN fatalities for 1998 was 47 across the whole of Queensland. Assuming that about 50% of these occurred in South East Queensland and if the 30% casualty rate applies to fatalities as well, we can infer that about 45 x 0.5 x 0.3 = 7 - yes an estimated (up to) SEVEN pedestrians died on SEQ local streets last year.

Realise also that it is by no means guaranteed that ANY of these seven people would have survived had the speed limit been lower, it is just a little bit statistically more likely.
Even in the unlikely event that all of these SEVEN survived under the new scheme, this would make only a 2.5% impact on the road-toll, yet other much larger factors have not been addressed – eg. seatbelts 12.2%, fatigue 12.1%, and alcohol still topping the bill at 17.6%. This gross misallocation of resources fuelled by a ever more hungry treasury, borders on criminal negligence.

Another aspect of the campaign that is quite despicable, is the use of children in the advertisements to reinforce the government case. The intended inference is that children are the big beneficiaries of these new initiatives. Once again the reality is quite different. Thankfully only a small number of children die on Queensland roads – Only 18 under 12 year olds died in 1998 (6.5%) and this includes children who were passengers involved in road accidents. Again it is indiscernible from the published statistics but that the number of pedestrian children killed on SEQ local roads is probably no more than one or two of the seven above would appear to be a reasonable estimate.

At this point we have to ask ourselves if we’ve been sold a pup. The best idea the Government can come up with (certainly the best managed in terms of public relations) might save one to three lives in 1999.

The media campaign alone for the introduction of the 50km/h limit is reputedly $3M, but of course this will all soon be recouped by the thousands of fines that are going to be handed out in the name of increased public safety.

Let's call on the government to agree, that if the pedestrian road-toll is not reduced this year, that the complete 50km/h project be abandoned - Surely that's fair?
 

Miscellaneous

Another interesting fact: All cars are designed to be able to travel (just barely) in top gear at 60km/h – It’s part of the engineering design spec. Now we have to drive in a lower gear causing more pollution and wear. (Heck, maybe Greenpeace will take up the cause?)

The State Government also seems to have forgotten their promise that, if the 50km/h local limit was introduced, that the main road speed limits would be reviewed and raised! Almost all of the 4 and 6 lane arterial roads in Brisbane still have a 60km/h limit.
It is also an engineering fact that increasing the travel speed of a road increases its effective traffic carrying capacity. Surely it is in the government’s own interest to take advantage of this fact so as to alleviate the need to widen streets and build more roads.
 

Speed – we are led to believe it is the number one cause of fatalities

The Government web-site claims  "Almost one in five fatalities is a result of speed" [ref 5] Put another way,
   "LESS THAN 20 PERCENT of fatalities is a result of speed"
In actual fact, the figure is much less than 20%. This is due to the fact that when assessing the cause of an accident, speed can be listed as a contributing factor, even if there are other more significant causes, such as the driver is found to have been well over the legal blood alcohol limit. In spite of this, The 1998 Qld statistics show only 34 out of 279 fatalities were classified as “speed was a contributing factor” (not, caused by speed or speeding – this distinction is important) This represents only 12.2%.

Can someone explain how less than one in eight, can be regarded as almost one in five? Ooops, Caught out lying again!

The number of accidents where excessive speed is the sole cause is actually only around 4%. [ref 6 ]
 

So why is speed the area that receives the most publicity and the most enforcement attention?

Answer: Simple - it is the easiest to enforce AND the most profitable for the government.

One final point that’s guaranteed to amuse.
The copyright notice on the roadsafety.net [ref 7] website states:
“The State of Queensland makes no statements, representations, or warranties about the accuracy or completeness of, and you should not rely on, any information contained in this publication.”

I guess that says it all.

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References:

1. Queensland Government braking distance chart 
2. Braking distances calculations based on realistic published figures
3. Roadsafety.net website - up to 30% casualies claim
4. Travelling Speed and the risk of crash involvement NHMRC study 1997.
5. Roadsafety.net website - Almost one in five fatalities is a result of speed
6. Research by SENSE in Canada 2-5% accidents attributable to speed
7. Copyright/Disclaimer message - roadsafety.net - Disclaimer for accuracy of all statements (classic!)

Also for further information see LINKS