Bicycle Accumulator - 32 bikes and counting

14 March, 2011

New blog up and running

My new blog about bicycling is up and running. http://christopherlhope.com/wp/

This blog will remain up, for a few months, as I transfer links and other data from one site to the other.

13 March, 2011

Hopefully, this blog will be moving sometime this spring or early summer. I reckon learning to use Word Press will take me that long. (I'm not very computer savvy).

I have my own domain now, and server space from Liquid Web. Nothing wrong with Blogger, but I want to expand a bit, and control the advertising.

Bicycle Safety

I've been reading Bike Snob by Bike Snob NYC.    It's funny and well worth your time.   Maybe when I'm done I'll do a bit longer and more detailed review.   For now though, the book has inspired this post on safety.

Bike Snob makes the point that cycling is hyped as dangerous by everyone, including many cyclists, bike manufacturers, and of course helmet manufacturers.    He doesn't conclude that one should go sans helmet, as does Mr. Mikael Colville-Anderson at Copenhagenize, but Bike Snob definitely seems to think the dangers of cycling are exaggerated.    It's my job to point out that the dangers are not exaggerated.

http://en.wikipedia.org/wiki/Air_safety

If you take a look at the wiki site linked above, and scroll down to the heading "Statistics", you'll see a table listing several modes of transport, including walking, and their relative dangers. Cycling is always near the bottom. In other words, cycling is always one of the most dangerous forms of transportation.

The tables give us the Deaths by three different measures; distance, time, and number of journeys.    By all three measures, motorcycles are the most dangerous form of transport - by whopping big margins. By two measures - journeys and hours- bicycles are the second most dangerous.     If measured in kilometers traveled, bicycles are safer than motorcycles, and safer than walking, but more dangerous than any other form of transport listed.

To go into a bit deeper, the stats are listed as "Deaths per Billion Journeys" (Journeys), "Deaths per Billion Hours" (Time), and "Deaths per Billion Kilometers" (Distance).    Again, cycling is the second most dangerous mode of travel when measured in deaths per Journey or per Hour, and third most dangerous when measured per Kilometer.

Now, which of these measures -Time, Distance, or Journeys should a cyclist use?    Well, one way to look at it is to take a tip from the airlines - e.g. use the stat that is most advantageous.    The air travel industry constantly tells us that airplanes are the safest mode of transport, and that's true, as long as one measures deaths per kilometer.   This is hardly surprising, as every time a plane lands safely it has racked up hundreds of thousands of passenger-kilometers (several hundred to a few thousand kilometers, multiplied by several hundred passengers).    We don't often find planes being used to transport one person 12 kilometers, as we routinely see with cars and bicycles.    It's the nature of air planes that they should rack up huge numbers of passenger-kilometers, so when the deaths are divided into this very large number, the "death rate" will be very low.    Or, to put it the other way 'round, air travel will be measured to be very safe.    Naturally, this is the measure the airlines prefer to publicize.

Look at the table that lists deaths per Journey.    Changing the measure changes the rating.   Suddenly planes are the third most dangerous way one can travel, albeit still safer than motorcycles and safer than our beloved bicycles.     The airlines don't publicize that air travel is more dangerous than going by boat, foot, car, van, train, or bus, when safety is measured as deaths per journey.

So what measure do bicycle advocates use - well, usually distance.   That way, they can truthfully say that being a pedestrian is more dangerous than being a cyclist, and as long as no mention is made that cycling is still the third most dangerous mode of travel, cycling starts to seem wonderfully safe.   It's safer than walking! Well of course, bicycles are going to rack up more miles compared to walking, just as planes rack up more miles when compared to cars. Divide the number of deaths into a larger number and you get a lower death rate.    If instead, we measure deaths per billion journeys, being a pedestrian is four times safer than being a cyclist.     You'll probably never see that fact on any other cycling blog.

So what's the right measure to choose?    Well, they're all correct, they just measure safety differently. A key thing is to understand that the safety of different modes of travel can change remarkably depending on what Death is being divided into - Journeys, distance, or time.

Notice though, that the safety of air travel varies markedly depending on the measure, whereas other modes vary much less.    Buses for instance, are either the safest or second safest mode by all three measures.   Rail is either second or third, under all three measures.   Bicycles share this relatively low variability.    They are, by any measure, the second or third most dangerous way to travel.

Bike Snob goes on about how dangerous cars are, but by any of the three measures we've looked at cars are four to fourteen times safer than bicycles.   On page 106 he suggests that "Using a car instead of a bike because it's safer is like climbing out the window on a rope ladder because of the remote possibility your staircase might be infested with termites".

Maximum points for rhetorical flourish, but no points for useful insight.    Even if you're just going to the corner store for a half gallon of milk, the car is still safer than the bike, and that's true whether we measure the deaths by time, distance, or number of journeys.

So am I suggesting ditching the bike and always using the car instead? No. but I am suggesting that we cyclists don't need to engage in mutual self-delusion.   Why should a cyclist blogger, or cyclist book author try to suggest to another cyclist, or worse, someone considering getting into cycling, that bike riding is really wonderfully safe and that there is nothing to be afraid of when cycling is, in fact, always one of the three, or two, most dangerous modes of travel?

Quibbles where quibbles are due-

One might reasonably ask why the tables list vans and cars separately.   After all, both are four wheeled motor vehicles, traveling the same roads.   Ok, combine car and van stats, and the results change somewhat. Bicycle deaths per journey are only 2.8 times greater than car/van deaths.   When we measure deaths/hours car/vans are 2.89 times safer.   When measured by kilometers, car/vans are more than 10 times safer than bikes.

Another quibble might be that the stats are not broken down by nation/province/city/rural or in other ways that might point up very real differences from one place to another.    For example, I'd be willing to believe that bicycle travel is relatively safer in Copenhagen than in Detroit.    The problem with broadly gathered stats is that they may not reflect local conditions.