Thursday, April 7, 2016

CityLab: Why Bike-Share Is Really Very Safe

Safer than personal bikes, even, according to new research.
Image Flickr/Mr.TinDC
A Capital Bikeshare station in downtown Washington, D.C. (Flickr/Mr.TinDC)
The history of bike-share in the U.S. is pretty short. One of the first American programs on record, in Tulsa, Oklahoma, isn’t quite a decade old, while larger programs in Minneapolis-St. Paul and Washington, D.C. have been running since 2010. Bay Area Bike Share (BABS) has been around since 2013. But the systems have already amassed a loyal following: Minneapolis’s Nice Ride has seen nearly 800,000 trips since 2011, D.C.’s Capital Bikeshare has seen 5.9 million, and BABS almost 350,000.
Remarkably, though, none of these trips have concluded in fatal accidents on the road, says a new analysis from the Mineta Transportation Institute.
This is not because cycling has suddenly become less dangerous: the Centers for Disease Control and Prevention says more than 900 bicyclists died in 2013. The relationship holds when the researchers examine non-fatal collisions, too. The MTI researchers find that in three major bike-share systems—D.C., the Bay Area, and Minneapolis—there have been fewer overall collisions per 100,000 trips compared to national collision rate benchmarks. D.C., in particular, has seen excellent numbers: 65 percent fewer vehicle-involved collisions than national benchmarks. So what are bike-share programs—and bike-share riders—doing differently?

Why so safe?

To figure out why bike-share users have stayed safer than cyclists manning personal bikes on American roads, the MTI researchers consulted industry experts and held focus groups in the regions studied. They emerged with two explanations.
The first credits the design of bike-share bicycles. These behemoths were built for durability—they’re stocky, heavy, and decidedly biased against speed. “I don’t think these bikes were designed for safety,” says Elliot Martin, an assistant research engineer at UC Berkeley who helped author the report. And yet, it looks like safety is a “side effect,” he says. Limiting the speed of these shareable babies makes it harder for their riders to get into wrecks. Additionally, many bike-share cycles are brightly-colored, and come equipped with lights, all of which make them easier to see (and avoid) at night. The lesson, particularly for new bike-share systems, may be pretty simple: don’t fix what ain’t broke.
A bike from Seattle’s Pronto! system, manufactured by Arcade Cycles (left) vs. a typical road bike (right). (MTI)
Another reason may go back to the new users that have glommed onto bike-share. This explanation is somewhat counterintuitive. It might seem that riders who have newly adopted a cycling commute might be, well, pretty awful at it, liable to careen into poles or other bikers. But the MTI researchers suspect it’s the opposite. New riders may be extra-cautious while aboard their borrowed bicycles, which could lead to fewer crashes.
There are other factors, too: Bike-share systems often pop up in dense, urban areas with at least a modicum of bicycle infrastructure, like protected lanes. Additionally, bike-share bikers are often maneuvering around slower-moving urban traffic, which decreases the risk of injury. (According to the experts consulted for the report, the ideal speed limit on a roadway with adjacent bike lanes should be between 20 and 30 mph.)
It should be noted that the researchers did find fatalities in other North American systems: Two people have died using bike-share in Canada, and one person died in Mexico. Additionally, the U.S. data doesn’t mean that bike-share is risk-free. “Some people can and do get very injured using bike-share,” Martin says.

The helmet conundrum

The report also adds to the mounting evidence against the efficacy ofmandatory helmet laws. Previous studies have found that mandatory laws arenot associated with lower rates bike-related hospitalization rates. And as the researchers write here:
[Bike-share safety] is definitely not due to increased helmet use, which is widely documented to be lower among bike-sharing users. For all their well-documented safety benefits, helmets, like seatbelts in cars, mitigate the severity of injuries when a collision does occur, but they do not prevent the collision from occurring.
The science of bicycle helmet laws is, to put it bluntly, pretty weird. As the MTI researchers point out, helmets are good—they do reduce the incidence of head injuries among riders. But when examining bicycling populations on the whole, researchers have found that mandatory laws disincentivize bike trips, especially those spur-of-the-moment ones. As Eric Jaffe wrote on CityLab, “In places where [bicycling is] unsafe, the laws may make riding a little safer, but are also likely to distract attention from initiatives, such as infrastructure upgrades, that would be even more effective.” In other words: if it’s a zero-sum game, let’s focus our energies on creating excellent bike infrastructure.
“Nevertheless,” the MTI researchers write, “the widespread use of helmets in this environment would unequivocally improve bike-sharing safety.”

Questioning “safety in numbers”

Another interesting takeaway from the report is that the researchers saw little evidence of the so-called “safety in numbers” thesis. This theory reasons thatthe more bikers riding the road, the more aware of them drivers will become.By that logic, more riders mean fewer crashes. This has been backed up by research: one landmark 2003 study of 68 California cities, 47 towns in Denmark, and 14 countries in Europe saw clear decreases in the numbers of pedestrians and cyclists struck by cars as the numbers of pedestrians and cyclists increased.
But the MTI researchers saw the number of collisions rising even as more bicyclists took to the roads. In the chart below, only Minneapolis-St. Paul saw a steady decline in collisions as bike-share use went up.
Comparing the rates of bicycle-involved collisions and bicycle commuting populations in Washington, D.C., Minneapolis and the Bay Area. On the y-axis, 1.00 represents the 2006 baselines for both bicycle-involved collisions and the bicycle commuting population. (MTI)
Martin, the Berkeley researcher, says this isn’t enough evidence to abandon the safety in numbers thesis altogether. It could be that these cities have not yet reached the necessary cyclist saturation to get the extra boost from newly woke drivers. “The safety in numbers benefit might be a factor in some point in the future,” he says, “but we couldn’t find it.”
Taken as a whole, though, the report serves as a handy cycling safety manual. Go slowly, carry a light, be cautious and aware of your surroundings, wear your helmet when you remember it, and, most crucially, advocate for more bicycle infrastructure and slower vehicle traffic. And Minneapolis-St. Paul’s Nice Ride is as nice as it sounds. (Final tip: never leave Minnesota.)


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