Conspicuity and Lamps #2

From John Murdoch

Cycle lights
I read Chris Jeggo’s blog article on lighting with much interest, and with the suspicion that I might have prompted the writing of it, having made it clear earlier the same day that I expected all riders on the Midweek Wayfarers ride to use lights on my ride that day; it was extremely foggy and murky.

Anyway, it is amazing how the same visual evidence can lead two people to come up with very different conclusions! Having followed a cyclist down the Vokes road who had no rear lights on at all despite the truly poor visibility, and then also seen how difficult it was to see some of our riders who had rear lights, but of poor intensity (I am sure I fell into that latter category!) my own conclusion was that it was sensible to use only lights with sufficient brightness.

I then considered Chris’ views about these being distracting to other road users. I am sure that they would need to be ridiculously bright to be distracting to car drivers, which means that they are suitable for solo riders. But what about group riding, which is what we do? I tend to be at the front of the group most of the time (not my superior pace, just that I happen to be a leader) so would be interested in views from further back in the peleton, but my limited experience does not support the view that the danger of a bright light to a rider behind outweighs the reduced danger through being more visible to other road users; we must distinguish between “danger”, which we must avoid, and “mild inconvenience”.

There is then the aspect of “which do you see first, the cyclist or his lamp?” My own conclusion is that, in poor visibility, if you see the cyclist first, then that is probably too late for the motorist behind, and it just means that the cyclist’s light is insufficiently bright.
So, having reached those conclusions, I am hoping that Santa will deliver nice bright lights, possibly from the east, but certainly from the CTC shop/Wiggle.
I mentioned at the start about drawing different conclusions from the same evidence base, confirmed by the fact that my own conclusion from knowing that a main danger to a cyclist’s life is a head injury is that wearing a helmet is sensible; I know that they may sometimes be insufficient and therefore ineffective, but I would rather wear one than not, just to improve the odds. Wonder whether that comment will lead to another strand developing on this blog topic!

Conspicuity and Lamps

 by Chris Jeggo

Scientific research has been done on this topic.  An important finding is that bright red and orange are the most conspicuous colours in daylight, but white is the most conspicuous at night.  DayGlo colours are even better in daylight because their fluorescent dyes convert ultra-violet to visible light, but they are no better than conventional dyes in the dark, when there is no UV around.  A good round-the-clock compromise is fluorescent yellow, which is why it is so readily available and so often used.

Reflective fabrics are brilliant at night but pointless in daylight except when visibility is poor enough to make the use of lamps desirable, i.e. when cars have headlamps on.  So, “high visibility” does not mean one simple thing, it could mean fluorescent, or reflective, or both.

 
Likewise, vehicle lighting is never simple;  compromises are necessary.  Consider motor vehicle front lamps.  The compromise here is between being able to see where you are going and not dazzling other road users who are also trying to see where they are going.  Main beam headlamps dazzle, so cars must have dipped headlamps, which are subject to stringent regulation and tested annually at MOT time.  Front fog-lamps are, I think, less regulated, but it is illegal to use them when it is not foggy, i.e. when the visibility is greater than 100m, so that they do not dazzle.

It is similar for rear lights.  Typical filament bulbs are 5W for tail lamps and 25W for fog lamps, so once again it is illegal to use fog lamps when it is not foggy.

These laws are sensible, they work.  You can verify this for yourself when out and about on the roads.  In daylight in good visibility you see an approaching vehicle before you see its lights, unless it is using unnecessarily bright ones.  When it is foggy you see foglamps and dipped headlamps at greater range than the vehicle itself, but this is not true of the less powerful side-lights/parking lights, so their use in fog is pointless.

(I am coming to cycle lights soon;  hang on in there!)

Less sensible are the modern laws requiring new motor vehicles to have daytime running lights.  On some models they create more dazzle than dipped headlamps;  you can observe this for yourselves.  In my view lamps should be used only when necessary to see or to be seen.  You might think it does no harm to use them at other times, but I am against anything which might cause drivers to use their eyes and their brains less than they do.  One should not create an expectation, however slight, that road hazards will be lit.  That would shift responsibility away from where it truly lies.

Here is another example, from my personal experience, of this shift of responsibility.  I once helped a driver from her ditched car after she failed to negotiate a bend through excessive speed.  One thing she said was, “I was going less than the speed limit”.  Has the modern proliferation of speed limits created a generation of motorists who think that they need do nothing more than obey the rules to avoid blame when things go wrong?  Police drivers receive much training on “The Safe Use of Speed”, much, much more than learner drivers.

 Cycle lamps are constrained far less than motor vehicle lamps, and some of the regulations are frankly illogical, so it is down to us to make rational choices about our equipment and its use.  We have to work out for ourselves how to see, be seen, and not dazzle.  I have had to stop my bike on the Basingstoke Canal towpath at night because I was completely dazzled by the headlamp of an oncoming cyclist.  His lamp may have been appropriate for a well-lit city street where it has to compete with tens of car headlamps, but not on the towpath, nor a country lane.  My headlamp is tilted down so that its beam centre hits the road roughly ten metres in front of me.  I can see far enough on an unlit road to be safe, including going downhill at, say, 20-25mph, and I know that I can be seen at a good distance because I can see reflective road signs way ahead.

Cycle rear lamps commonly used are good enough at night but ineffective in daylight or poor visibility – apply the “Which did I see first, the cyclist or his lamp?” test.  High intensity rear lamps that are bright enough to increase conspicuity in poor visibility cause dazzle in other circumstances.  If you want to use one, go to the back of the group.

I worry that if we all use lamps in daylight as a matter of routine, rather than as necessary, then eventually the motoring lobby will seek legislation making daytime lighting compulsory.  Don’t think it couldn’t happen.  The motoring lobby has a long, well-documented history of trying to shift blame on to accident victims.  Why else would my inbox contain a pile of emails entitled “E-Petition – Assumed Liability Road Traffic Law”?

I’ve rambled on quite long enough, and have advocated the thoughtful approach, so I leave you to draw your own conclusions!

Proof of Concept Test "Buzz Ride" – 24 November 2013

Louise Gagnon writes… 

Buzz rides?  Yes, shorter, harder, and faster Sunday morning rides for those who are “time poor” due to family/career responsibilities and therefore can only afford a 3 hour outing. We are planning on starting such twice monthly rides in March 2014 but first we had to iron out the bugs. And thus 7 of us departed Guildford at 9 AM on our fast machines. We finished at 11:30 AM after a great 36 mile ride at an average pace of 13 MPH, including 700 meters of elevation. Much feedback was gathered at the coffee stop following the ride; thanks everyone!  All we need now is to secure the participation of enough Ride Leaders, preferably on a roster basis so that a leader only leads once every 6 weeks or so. Interested in ride leading Buzz Rides? You don’t need to currently be a Ride Leader- we’ll sort that out.  Please give me a shout at chair@ctcwestsurrey.org.uk.  

 
L to R:  
Pat Daffran, Louise Gagnon, Phil Hamilton, John Child, Ron Griffin and Gillian Spencer (Photographer: Jules Lowe).  

December 2013 Rides #2

Next it was the turn of the ‘Sunday’ riders – those hard men who nevertheless enjoy a good Christmas nosh as much as anyone – perhaps more so: they’ve usually ridden further to get it! Once again it was an excellent ride to the Blue Ship, that well hidden gem wot sells ultimate flat beer. I tell you, I could so easily have had that second pint – and then struggled with the home run – big time!

Thanks to Clive (on the right) for co-ordinating this motley group and leading wonderful rides all year. I hope you’re looking forward to being President of the club for about 50 years sometime in the future – you deserve it.
And here are a few more shots from this superb day of cycling: the weather really couldn’t have been better for December. Don’t forget you can click on an image to see it bigger!

December 2013 Rides #1

It’s that time of year when the ride ‘lunch’ has greater cachet. Not quite sure why because lunch is always good on our rides – well done, ride leaders, you invariably choose the venue well.

Last Sunday’s Guildford and Godalming Wayfarer’s ride advertised the lunch as a Christmas lunch! Well why not! I saw nothing particularly festive eaten, but it was still a good event, with a good turnout. And here everyone is…

 Group leader, Peter Fennemore, is resplendent in red top. Job well done, Peter, thanks from everyone for a great year of rides
There’s Roger Philo, our President, in his AUK top (2nd left) and Louise Gagnon, our Chair (person) in blue (2nd from right)

Here are a few photos from the ride…

Who’s that chap chap riding like he was in France? Never seen him before!