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This interesting article was posted on another forum, so I thought I would post it here. The guy who wrote it is also a member of our forum "The Spin Doctor" (albeit that this was due to a case of mistaken identity 
). I have to add he is an advanced motorcycle instructor and that he writes many articles for among others the MAG (motorcycle action group), and he also wrote the text for the Lucky 13 cartoon (often used by motorcycle magazines here in the Netherlands). Some of his articles can be found on his site: survivalskills.co.uk - advanced motorcycle rider training for all motorcyclists... because it's a jungle out there When I asked him if I could quote this thread he said no problem but asked me to show his creative commons deed. enjoy it has some really good tips and info (well i thought so):
Note: Please give The spin Doctor any thanks and/or Rep as I just copied his thread :spank:.
). I have to add he is an advanced motorcycle instructor and that he writes many articles for among others the MAG (motorcycle action group), and he also wrote the text for the Lucky 13 cartoon (often used by motorcycle magazines here in the Netherlands). Some of his articles can be found on his site: survivalskills.co.uk - advanced motorcycle rider training for all motorcyclists... because it's a jungle out there When I asked him if I could quote this thread he said no problem but asked me to show his creative commons deed. enjoy it has some really good tips and info (well i thought so):The Spin Doctor said:Urban Masterclass Part One - the pros and cons of conspicuity aids
Thirty years ago, a man called Harry Hurt (really!) released a ground-breaking study into motorcycle accidents.
Harry and his expert team spent 1979 and 1980 racing to the scene of motorcycle accidents in southern California to try to work out why and how the riders had crashed. When they got there, they talked to witnesses, the attending police, any involved drivers and where possible the riders themselves. They followed up over 900 accidents on site and reviewed a further 3600 accident reports.
The findings were presented in 1981 as ‘Motorcycle Accident Cause Factors and Identification of Counter-measures’, better known today as the ‘Hurt Study’ or ‘Hurt Report’.
It was the first half-way scientific study of motorcycle accidents.
The full report is over 300 pages long, and Hurt and his team drew no less than 55 main conclusions. I’m not going to repeat them here (a search on Google for 'Hurt Report conclusions' will find them for you) but I will summarise one key area:
Approximately three-fourths of these motorcycle accidents involved collision with another vehicle, which was most often a passenger automobile. Intersections are the most likely place for the motorcycle accident. In multiple vehicle accidents, the driver of the other vehicle violated the motorcycle right-of-way and caused the accident in two-thirds of those accidents. The failure of motorists to detect and recognize motorcycles in traffic is the predominating cause of [multiple vehicle] motorcycle accidents. The driver of the other vehicle involved in collision with the motorcycle did not see the motorcycle before the collision, or did not see the motorcycle until too late to avoid the collision
Before the '80s were over, a UK-based study conducted by Booth looked at nearly 10,000 motorcycle accidents in the predominantly urban Metropolitan Police area.
It concluded that nearly two-thirds (62%) were primarily caused by the other road user. Half of the accidents were caused by car drivers, and 10% by pedestrians. The report found that two-thirds of motorcycle accidents where the driver was at fault were due to the driver failing to anticipate the action of the motorcyclist.
Notice the similarities?
As the authorities and rider bodies themselves picked up on the problem that motorcycles simply weren't being seen in traffic and that many accidents happened when drivers pulled out in front of riders, one obvious suggestion was that motorcyclists needed to make themselves more visible.
The result was the use of day riding lights (DRLs) and other conspicuity aids such as high visibility clothing (hi-vis) were suggested in books like the Highway Code and in some cases became mandatory (permanently illuminated turn signals in California, headlights-on in France and Australia, CBT instructors and trainees required to wear day-glo bibs in the UK - just a few examples).
Yet there were warnings that this might not be a fully effective strategy. From "Motorcycle Safety - a scoping study" published by the Transport Research Laboratory in 2003:
"The conspicuity problem appears to be partly associated with car drivers learning visual strategies that are not very effective at detecting motorcycles, and there is potential to address this by training – although it is not clear how effective this would be in the long term given that the basic problem may be the relative rarity of motorcycles."
So what are these visual strategies they are talking about? Somewhat simplified, it's down to three things:
- the way the eye works (a very narrow zone of clear focus right in the very centre and a large 'fuzzy' area where what seems to be a clear image is actually filled in by the brain from memory, rather like the way software interpolation on a digital camera 'invents' detail from the surrounding pixels)
- the way the brain interpretes what the eye sees (it detects what it sees using movement or light/dark contrast, moves the eye so the object is in sharp focus, but then identifies what it sees from a 'database' of shapes it knows from prior experience are important - thus drivers tend to be aware of cars and trucks, but not bikes and cycles.)
- where and how drivers look (research shows they look for GAPS, not vehicles, because that's what they need to pull out into. So they tend to look behind you when you're close to them and they look for an average of just half a second which isn't long enough to scan and focus on the full area between that gap and close up to their car.)
So how does that lead to 'detection failure'?
First thing to understand is that your brightly coloured and illuminated bike isn't moving relative to the background until you are very close to the driver - it's called 'looming'. So you're not picked up by the 'motion detection' system particularly when drivers are glancing rapidly left and right.
Second thing to understand is that your brightly coloured and illuminated bike only stands out if there is a strong contrast against the background (incidentally, hi-vis vests are too small to be effective particularly behind a fairing so use a SLEEVED hi-vis jacket), and an increasing number of vehicles now also use DRLs, so the 'contrast detection' system fails too.
In both of these cases, even if the driver appears looks straight at you because you're between them and the gap they intend to use, they tend to look behind you so you're out of focus. Combined with the failure to detect you via motion or contrast, it means from their perspective the road ahead of the gap appears to be clear (even though there is a bike in it), so they pull out.
This kind of behaviour even has a name - it's called "looked but did not see".
As you are riding up to a junction where a car might pull out, another important concept to understand is 'time to collision', because this effectively defines:
- the 'evasion zone' which is the piece of road where you can avoid a collision with an emerging driver by braking/swerving
- the 'killing zone' which is the piece of road where, if the driver emerges, nothing you can do can avoid a crash
Right, that's some background and theory. So it's about time for some practical advice.
The main BENEFIT of hi-vis and DRLs is to help the driver to see you when you're five or even ten seconds and more from collision (which is miles away in urban riding) and to REMEMBER you're there when you enter the 'killing zone' a few seconds later, (as I said, that's the zone where YOU cannot avoid a collision if the driver starts to emerge).
The main DRAWBACK of hi-vis and DRLs is that just when you'd imagine they would be most effective (because you're so close to a driver it seems obvious he can't fail to see you), is when they DON'T work and that's when you're at risk of a "looked but did not see" accident.
Now, that sounds bad but frequently this happens when you are still outside the 'killing zone'. The car driver doesn't want a dent in his car so as I've explained he'll have looked far enough down the road that he doesn't get hit by a truck or a car.
When he pulls out, because he didn't see the bike in that gap, you're still far enough away that he'll miss you! Even if he does a double-take halfway out of the junction, panics and jumps on the brakes blocking the road completely, you can still stop! So from your point of view it's a near miss, perhaps a bit scary as you grab the brakes, but no more than that.
Unless:
1) you grab the brakes and fall off or fail to brake at all and plenty of riders make both mistakes - we'll be talking about emergency stops in another article.
2) you're riding much quicker than the traffic around you, in which case the gap WON'T be sufficient for you to stop - so we'll talk about speed in traffic in another article as well.
The REAL danger time is when a driver pulls up at a junction and you're already on top of it, just about to enter or already within the 'killing zone'.
They'll look straight behind you to where the gap actually is, and pull out without EVER being aware you're there because the brain hasn't had time to detect movement or recognise the outline of "BIKE + RIDER". DRLs or hi-vis make no difference at this distance.
As the car pulls out blocking the road in front of you, you haven't time to brake or swerve to avoid the collision. The best you can do is brake as hard as possible and reduce the severity of the impact. Not a great scenario for the thousands of riders who find themselves in it every year.
And that's the point I want to make about the effectiveness of DRLs and hi-vis. Thousands of riders across the world are still injured or killed in this self-same accident that was identified thirty years ago.
If hi-vis and DRLs really worked, we'd find a big shift in the LOCATION of accidents since the 1980s when those first serious studies in accidents were done when riders didnt use hi-vis & DRLs.
And we don't.
We're still having virtually the same proportion of junction accidents 30 years on. There's been a slight drop in the FREQUENCY of accidents per vehicle mile, but the same accidents are happening in the same places in more or less the same ratios as ever.
So you're nearing the 'killing zone' and you're worried about an emerging car. What can you do? How can you defend yourself?
Well, the first line of defence that most riders totally forget is the HORN. If you are in ANY DOUBT AT ALL, hit the button! Even if you're a bit late and the driver's started to move, sounding the horn might get the driver to stop again!
Your second defence is SPEED. Go slower and the 'killing zone' gets significantly smaller thanks to physics: as you HALVE your speed, you stop in one QUARTER of the distance - so even SMALL reductions in speed, say from 35mph to 30mph, have significant effects on stopping distance, effectively making your evasion zone 'last longer' on the approach to the junction.
And your final defence is AWARENESS. If you know it can happen, and you expect it to happen, you can shave massive amounts of time off your reactions. Remember those stopping distance figures on the back of the Highway Code? It turns out that in real accidents bikes take much LONGER to stop. Why? Because the rider wasn't expecting the car to pull out and had to think... "hang on a minute, that bloke's not stopping, oh sh********TTTTT" That all takes time and massively lengthens the 'killing zone'. Look at each and every junction as a place where a car COULD pull out, cover the brakes and think "what if...?" Your reactions will be up to two seconds faster.
Something I'll be looking at in future posts is how you can position yourself for better view ("see and be seen") and how to use active changes of position so that you can help avoid the looming problem. I'll also cover how to use hi-vis effectively.
Ride safe out there!
Note: Please give The spin Doctor any thanks and/or Rep as I just copied his thread :spank:.
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