About bicycle lighting and onions

A chance meeting can lead to unexpected discoveries.

I met and spoke with Kurt Cibulski following a reading from a new book by its author, a mutual friend. I had arrived at the reading by bicycle; Kurt and I were talking bicycling. Kurt explained that he has a seizure disorder. The bright, rapidly-flashing LED headlights that bicyclists are increasingly using can initiate a seizure for him. “Who’d ‘a’ thunk it.” thought I.

Who? A proper, national standards-setting body, because someone, somewhere, would have brought the issue to its attention. On second thought, it’s obvious. Flashing lights are well-known to trigger seizures.

It’s also a truism that flashing lights draw attention. Many bicyclists ride in urban areas with overhead lighting, and don’t need a steady headlight beam to guide their way. But on the other hand…there’s the seizure problem.

Without careful standards setting, issues like this slip through the cracks. Designs get based on whim, commercial appeal, economies of production and avoidance of liability risk.

In the USA, individual cyclists are held responsible under state laws for using lights at night, but law enforcement is near-nonexistent, and many cyclists don’t use lights. The USA does have a Consumer Product Safety Commission, which, under pressure from the bicycle industry, has set standards — weak standards — only for retroreflectors on bicycles, never for lights. Retroreflectors only work for drivers whose headlights are pointed at them, and do not light up for the pedestrian stepping off the curb, the motorist in the cross street ahead, two bicyclists on a path approaching each other head-on. Bicycle manufacturers can point to Federal regulations and say that they are doing something for nighttime safety, while not being held responsible for these deficiencies.

This situation holds some ironies and unintended consequences beyond the obvious one that cyclists are being injured and killed for want of lights. The lack of standardization in the USA has given lighting manufacturers free rein to innovate, and has led to the availability of some very fine bicycle lighting systems. In the USA, when you see a cyclist with a light, you will probably see that cyclist from a good, long distance, because the light is a very good light.

In Germany, by way of contrast, lights are required on new bicycles. Manufacturer pressure comes to bear in a different way. To keep expense down, most lights only meet the letter of the law and are are less bright, and much less reliable, than the good ones sold in the USA. Bureaucratic inertia has compounded the problem: Germany requires bicycle lights to be powered by a generator. That made sense 40 years ago when battery lights were weak and battery replacement was expensive. Today’s efficient light-emitting diodes and high-capacity rechargeable batteries make battery lights economical and practical.

Generator lights also have improved, thanks to advances in technology and to discerning European cyclists’ demand for better lights that also meet the requirements of their laws — but a good generator lighting system can cost half as much as the bicycle on which it is installed.

A restrictive legal climate leads to this kind of market distortion; contrast this with the wider scope of innovation and slip-through-the-cracks issues in the US market.

I can’t help noticing that kiosk “bike share” (actually rental) bicycles that are becoming popular in American cities all are equipped with LED headlights and taillights, powered by a generator in the front hub. It only makes sense. The rental agencies have a more direct liability exposure than bicycle manufacturers who sell to individuals. But — the lights on the rental bicycles flash, because the generators produce alternating current and the output is not smoothed. Possibly also because flashing lights are popular and nobody though of the seizure-disorder issue.

Where are we heading with all this? I think that we’re approaching a political tipping point where regulations requiring lights on at least some kinds of new bicycles might be possible in the USA: both because of an increase in interest in utility cycling, and because improving technology had made bicycle lights much less expensive, more reliable and more compact. I mean, if little children can have flashing LEDs in the soles of their shoes, just to look cool, it isn’t much of a leap to think that every new utility bicycle could be equipped with lights.

But we also need to be smart, and look forward as technology improves, so regulations don’t box us in with outdated technology and inferior products, as in Germany.

Now, about those onions:

To give Kurt proper credit in this article, I asked his name and came up with another unexpected discovery. He spelled his name, and then volunteered, “Cibulski means ‘onion man’ in Polish. It’s a pan-European word.” Yes! Again, who’d ‘a’ thunk it? German, Zwiebel. Spanish, cibolla. I looked it up, and found variants in languages as diverse as Basque, Czech, Gaelic, Norwegian, Romanian…

I suppose that there’s another parallel, besides the two unexpected discoveries. Bicycle lighting issues, with all the political and technological complications, peel apart in layers like an onion, too.

Thanks, Kurt!

11 Responses to About bicycle lighting and onions

  1. So, what about flashing tail lights while we are at it? Those are explicitly legal some places now.

  2. I suspect that flashing red taillights pose a problem too, but I don’t know to what extent. Expert, research-based knowledge is needed to answer this kind of question. I do understand that the flash rate is an important factor in triggering seizures — so, a well-chosen flash rate might at least partially avoid the problem.

  3. Flashing headlights are not a good idea for cyclists either under fully dark conditions. They make it harder to estimate the approaching cyclists speed. But in low-light conditions (dawn, dusk, rain, fog) they’re great at drawing motorist attention.

    What about flashing motorcycle headlights? Those have been around for years.

  4. I suspect that there are more reasons why flashing headlights are a bad idea. It is more difficult to judge the speed and distance of a flashing light, for one thing. I prefer that my headlight not waver either. I have my headlights mounted on the top tube so that they present a steady beam (). It definitely helps with my seeing, and I suspect that it help with my being seen too, but I don’t really know.

    I have heard differing opinions on flashing taillights, and I would like to hear something more definitive on that. Also, I wonder if it might be better for drivers approaching from behind to see reflected light instead of direct light. This might facilitate speed and distance judgements. Maybe taillights should be angled down for this reason. I would be interested to hear your thoughts on this, John.

  5. I don’t know if my decisions are backed up by any research, but for what they are worth: I prefer a steady headlight, but that’s partially because my regular commute is not completely along well-lit streets, so I do often need a steady headlight for seeing the road. Trying to see with a blinking one is very annoying. In the back, in addition to the standard equipment red reflector, I use two taillights, one on the seatpost and one on the back of my helmet. The seatpost one is set to a slow blink, blinking to be noticeable because it is at a similar height to car taillights, but slow because I too think a fast blink is more distracting. I set the helmet taillight to solid because I’ve heard that solid is easier for the eye to track, and being above the height of car taillights, I would think that noticing it wouldn’t be as much of a problem.

  6. I’m a fan of the conspicuousness of flashing headlights in twilight or broad daylight. Yes, I started riding with flashies on after getting left crossed in broad daylight, wearing an orange vest, while riding in the center of the lane. “I just didn’t see you” said the professional driver. Sigh.

    I talked about flashies with a professional advocate for epileptics. Everyone has a different sensitivity, but I get the impression that slow – say 1 Hz – is pretty much known to be non-threatening. That’s about the frequency of most flashers, with the notable exception of one popular Madison-based brand.

    Also, brightness matters. Probably an inverse square law there.

    I’m not sure, but if you can have a seizure, are you allowed to hold a driver’s license?

  7. Interesting article. Do you think it’s possible that the need for bright bicycle lights in Germany is less than in the United States? Perhaps fewer cars on the streets, better street designs, better lighting, positive attitudes of drivers towards cyclists, and laws protecting cyclists all combine to make the brightness of bicycle lights a non-issue.

    I’m not convinced that bright lights are good for cycling, anyway. When a cyclist is killed by a driver, the media likes to report on how invisible the cyclist was: dark clothing, no lights. I dread the day when they start reporting on how his lights were not bright enough. At what level of illumination is a cyclist considered seeable? How many lumens is enough to shift the responsibility for seeing to the driver? The safety “arms race” is what cars do (“Seat belts! Airbags! Side airbags! Drive like a maniac, because you’re the safest of all!”). I like to think that cycling espouses a more equitable culture. I don’t want to be blamed for driver’s negligence if my bike is not bright as my friend’s.

    On the other hand, as a geek, bright lights give me wings. If car batteries didn’t weigh 20 pounds, I would have automobile headlights on my bike! :)

  8. I have experimented with several lighting arrangements and reflective clothing and find they can make a huge difference in motorist overtaking behavior at night. My current lighting arrangement consists of a 750 lumen tactical flashlight as a headlight, a solid red tail light, and white blinkies mounted in front and back.

    I was surprised to find that reflective gloves made the biggest difference of all. I extend my hand, rotate the wrist up and down, and create a flashing effect in the headlights of the car coming up behind me. By day, the first car ignores a hand signal for a left turn 40% of the time. By night, the first car slows down 90% of the time.

    I’ve also experimented with a laser pointer that casts a faintly visible beam of green light down to a bright dot on the pavement about three feet to the left. The movement and vibration of the bike causes a strange “jiggling” effect in the dot. Motorists keep at least another foot or two away from that dot while overtaking. (The legality of such a lighting system is questionable at best so I no longer use a laser.) I would use a “Down Low Glow” light tube if Rock The Bike ever sells them again.

    Mavic “Signal” Jacket
    http://www.chainreactioncycles.com/Models.aspx?ModelID=54931

    Reflective Work Gloves
    http://www.amazon.com/gp/product/B002XISTXW/ref=oss_product

    Down Low Glow LED Light Tube
    http://rockthebike.com/lights/downlowglow

  9. Pingback: Linking to some useful information aobut bicycle headlights | John S. Allen's Bicycle Blog

  10. When I’m riding at night, I use steady front and rear lights. I never really bought into the flashing light craze that we’re in the midst of right now, but every light I have bought in recent years has ‘flashing’ as the default mode. I wish I didn’t have to double-click my lights to get them to put out a steady beam. It seems manufacturers have yet to figure out that allowing us to set the mode once only is far more efficient than having to do it every single time we switch the light on.

  11. “If you are at risk of seizure, are you allowed to hold a driver’s license?”
    Not in the UK, but it’s voluntary – doctors advise.

    Epilepsy – I looked into this 5 years ago – one instance of a cyclist seizing while attaching rear light to his own bike ( range = arms’ length )

    Flashing front or rear can be legal in the UK, but they must have a steady mode, for some reason and output 4 candelas, IIRC.
    https://www.gov.uk/rules-for-cyclists-59-to-82
    “Flashing lights are permitted but it is recommended that cyclists who are riding in areas without street lighting use a steady front lamp.”

    I use steady+flashing lights both fore (white) and aft (red) – 4 total.
    Gives some resilience if one fails.

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