Monday, 26 December 2011

Speed kills

A favourite amongst safety campaigners, but often ridiculed by motorbike riders, particularly the sport bike riders is the simple phrase 'speed kills'.

Here are a few quotes from The Biker Forum

"What a load of crap, I can't believe any biker would come out with this sort of drivel - lack of control kills, not speed. Are any of the relevant authorities concentrating on that? Are they f*ck :rolleyes:"

"Whoever dreamed up the statement "speed kills" wants hanging. Its the sudden stop that kills"

"Speed does not kill and we only have speed cameras because we have a daft road safety policy based on the misconception that speed kills"

"I'm not advocating driving like an idiot (the road is NOT a racetrack), but the idea that speed and ONLY speed kills is the preserve of the deluded"

There is clearly a complete failure to understand what happens in a road crash/accident whatever you want to call it. Accidents are made up of three parts


Inattention is the most common cause of an accident, or as the law puts it, driving "without due care and attention"

Not looking properly, failing to take into consideration road conditions or the amount of traffic and losing concentration make up the bulk of causes. The biggest single type is known as right of way accident where basically two vehicles want to be on the same bit of road at the same time. That is followed by loss of control on bends and overtaking or filtering.

However, excessive speed for the conditions removes some of the chance you have to avoid the collision in the first place.This can affect any compensation claim resulting from an accident

Here is one of the examples show by the compensation website

A motorbike overtaking at excessive speed hits a car doing a u turn. The biker was held to 100% responsible as his speed meant he had ignored how his speed affects his ability to avoid potential hazards.


Examples of the type of accident are rear end collison, side impact and loss of traction causing a fall or skid


This is the part that those who say speed does not kill have failed to grasp. It does not matter what the cause or type of accident that you have, the severity and survivability of the accident is determined by the speed at the point of impact, or as one biker put it, the sudden stop that kills.

From a Norwegian study in 2004 on speed and accidents

"The main findings of the research presented in this report can be summarised as

1. There is a strong statistical relationship between speed and road safety. When the mean speed of traffic is reduced, the number of accidents and the severity of injuries will almost always go down. When the mean speed of traffic increases, the number of accidents and the severity of injuries will usually increase.

2. The relationship between changes in speed and changes in road safety holds for all speeds in the range between about 25 km/h and about 120km/h.

3. The relationship between changes in speed and changes in road safety can be adequately described in terms of a power model, in which the relative change in the number of accidents or accident victims is a function of the relative change in the mean speed of traffic, raised to an exponent. The
following exponents summarise the effects of changes in speed:
a. Fatalities: 4.5
b. Fatal accidents: 3.6
c. Seriously injured road users: 3.0
d. Serious injury accidents: 2.4
e. Slightly injured road users: 1.5
f. Slight injury accidents: 1.2
g. Injured road users (severity unspecified): 2.7
h. Injury accidents (severity unspecified): 2.0
i. Property-damage-only accidents : 1.0

4. Several other mathematical functions may describe the relationship between speed and road safety, but the generality and simplicity of the power model makes it superior to other models. The model is, however,
not necessarily valid outside the range of speeds found in the present study (from about 25 km/h to about 120 km/h).

5. The relationship between speed and road safety is causal and can be explained in terms of elementary laws of physics and biomechanics. Speed is clearly a very important risk factor with respect to both accident
occurrence and injury severity."

Anyone with a basic knowledge of physics and some common sense will understand that kinetic energy transfer at the point of impact and its effect on the human body is what causes injuries. The higher the speed, the more kinetic energy there is flying around and the more severe injuries are likely to be. (I accept there is such a thing as a lucky escape, but people can also die from very minor collisions).


Speed kills refers to the impact speed has on the severity of an accident which in turn determines survivability. The higher the speed the less survivable an accident will be. Speed also robs the rider of opportunities to avoid the accident as the situation develops. This superb safe driving commercial expalins that in terms even the daftest of biker should understand...

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