Very often, I suspect, these accident victims have Federal Consumer Product Safety Commission approved- and required- reflectors on their bikes.
Roughly once per night in the USA, a person is killed on a bicycle after dark. This point is not hypothetical-our nightly accident rate shows that. This list is surely incomplete, but it makes a point: many factors can prevent a reflector from beaming light at the intended observer. The reflector surface can be abraded, covered with moisture or dust, or otherwise altered in a way that wrecks its optical performance.Or powered by a Lucas electrical system in the throes of an 8-volt brownout. Or the headlights may be mis-aimed or covered with dirt.
REFLECTOR 2 CRASHES DRIVER
The driver may have a burned-out headlight (possibly a lethal problem if it's the left headlight-generally, the right headlight's observation angle is too big for good reflector performance).(Howzat? The farther light travels through fog, the more the light gets absorbed-and light from a reflector is making a round trip, twice as far as light from an active light source.) Fog can completely hide the reflector when other lights remain visible.(The angle between the light source and the driver's eye is the " observation angle".)
The driver's eye may be outside the narrow cone of light which the reflector sends back to the light source. (If you look at bikes parked on a campus bike rack, you'll see reflectors aimed in all sorts of dysfunctional directions.) It can be tilted at an angle (" entrance angle") that severely degrades its optical performance. It can be anywhere outside the beam of a driver's headlights. It does, however, have other limitations. Why would a reflector decide to malfunction? And how could it? It doesn't have electrical components to fail, like, say, a British car. But reflectors don't work at all if those conditions aren't met, and many well-defined bicycle crash types occur in situations when we can expect reflectors to not work.įew people understand how easy it is to wander outside the range of conditions in which reflectors will work. Those conditions happen to prevail in most of the nighttime driving we do, so we get the impression that reflectors work most or all of the time. There is a very scientific answer: reflectors work only under very specific conditions. So here's the seven-million-dollar question: If all these reflectors are so darn bright and easy to see, how come the bike safety nerds insist you need active lights to be seen at night? All these reflectors will appear bright, and very easy to avoid. If bike riders are out, you'll see their pedal reflectors. If you go for a drive tonight, you'll see reflectors shining brightly from mailboxes.
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