Peter Rosenfeld
Mon, 29 Jul 2002 06:50:03 -0700
[EMAIL PROTECTED] writes: > FYI : Phila region has way less than 6 bike death a year. there is maybe 2 a >year, tops. some years there are none. ped falalities in phila are way higher, >but even that is about 10 a yr, sometimes less. I based the estimate on the population of Philadelphia region ( I assumed 3 million people for the region, but for simplicity did not take into account the fact that urban areas tend to have fewer fatalities per capita). I'm glad it is too high. In any case, this is the problem with using "fatalities" to declare a facility is safe. For example , a number of studies have shown that door-zone bicycling is a significant cause of serious injuries in urban areas. Assuming a proportional fatality rate, this will result in a fatality every 4 to 8 years or so. Kinda lost in the noise. Fatalities are just too rare for statistical use. You need to look at accidents and injuries. For every fatality there are hundreds of serious accidents resulting in serious injuries. The Santa Barbara study showed that building door-zone bike lanes correlated with a more than doubling of doorings in that city, resulting in doorings becoming their biggest category of serious bike accidents. Unfortunately, I don't believe our area keeps very good records on the causes of car/bike and bike-only accidents. If anybody knows of any, please let me know. So I typically rely on other areas and studies that do try to make these measurements. SDuch measurements are an important part of introducing experimental traffic facilities that go against accepted practices for vehicles. And when one of these rare fatalities does occur, it needs to be looked at carefully. Perhaps it is simply a freak occurrence of no real significance. But it can also be the "tip of the iceberg" for a very serious design flaw that may be causing thousands of serious accidents. I believe that door-zone bike lanes fit into this category. Accidents caused by dooring ( with or without bike lanes) are very significant in urban areas. No facility should be designed that supports such dangerous behavior (or any other such behavior, in my opinion). And such facilities can actually increase the behavior, as the Santa Barbara study shows. The BCGP states that facilities increase "perceived comfort" and offers that as a justification for the facilities. But when this "comfort" causes people to bike in a dangerous way, that is not a good thing. This "comfort" approach to facility engineering is the opposite of accepted engineering practices. People are getting injured and probably killed because of such a mind set. -Peter Rosenfeld ---- You are receiving this because you are subscribed to the Bicycle Coalition of the Delaware Valley list named "bike." To subscribe or unsubscribe or for archive information, see <http://www.purple.com/list.html>.