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Archive for the ‘bicycling’ Category

You see these stories in the news all the time. A bicyclist gets hit by a car and suffers a major head injury. It could have been much worse, we are told, but thankfully he was wearing a helmet. A shattered bike helmet is shown, with the implication that this could have happened to his skull:

helmet

While pictures like this are scary and dramatic, they are actually further evidence that bike helmets are ineffective. This helmet did not function in the way it was intended. In fact, it failed spectacularly.

Let’s review the physics of a bike helmet. They are constructed out of polystyrene foam (styrofoam) which is supposed to compress in a collision. This compression spreads the force out and reduces the acceleration of the brain as it smashes into the inside of the skull. At least that is how it is supposed to work — under ideal laboratory conditions where the impact force is perpendicular to the helmet. Actual collisions are chaotic events involving complex interactions. When subject to an oblique impact, the styrofoam will typically crack and break off without compressing. This is what appears to have occurred in the helmet shown above. If there is no compression, then it is unlikely the helmet absorbed the impact.

What is unfortunate about these kinds of news stories is that they give false hope about the effectiveness of bike helmets. And rarely do these stories ever mention the dangerous road infrastructure that caused the crash to happen in the first place.

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We all know that mandatory helmet laws discourage cycling. But even after such laws are repealed, the effects can linger:

The city of Dallas has decided that Edward Adkins doesn’t need a bicycle helmet or a bogus fine and arrest warrant hanging over his head.

Adkins received a $10 ticket for failing to wear a bicycle helmet in September 2014, even though the Dallas City Council had changed the city’s safety ordinance months earlier to only apply to minors. Adkins said he couldn’t afford the ticket, which caused the fine to balloon to $259 and turn into a warrant for his arrest.

Adkins said he didn’t show up to court because he didn’t have the money to pay and thought he was guilty. He didn’t know the law didn’t require him to wear a helmet until a reporter told him.

He ended up giving away his bicycle because he didn’t want to pay for a helmet.

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NTSB investigates a bicycle crash

The NTSB has taken the highly unusual step of actually investigating a bicycle crash:

The National Transportation Safety Board is investigating the Kalamazoo bicycle crash that killed five people and injured four.

Officials with the NTSB confirmed Friday the agency is investigating the crash, and said its team already is in Kalamazoo.

NTSB spokesman Eric Weiss said the team will look at all aspects of the incident, including how it happened and how the truck hit the bicyclists. He said the team will reconstruct the crash and find out if there are any safety issues that could be improved, from the vehicles involved to the road.

Weiss said the NTSB is investigating because the agency has taken an interest in the case, and not at the request of local authorities.

“This is such a singular event that we wanted to look at the issues behind it,” said Weiss, who acknowledged it’s unusual for the NTSB to investigate crashes involving bicycles.

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Bulb-outs, while useful in most cases, do have a number of drawbacks. They are very expensive to build, and often cause conflicts for bike lanes. It is much better to do these projects as full-blown Protected Intersections — which as it turns out can be much cheaper:

In 2010, Berkeley received a Safe Routes to School grant to add pedestrian bulb outs at this busy intersection. Hundreds of students cross this section everyday, which connects the North Berkeley Branch Library with neighboring parks and schools. Bulb outs shorten crossing distances for walking and place pedestrians where they are more visible to drivers. However, because bulb outs cause water to drain differently on the street, they are costlier to design.

When the project was delayed due to engineering staff constraints, Caltrans threatened to rescind the grant to fix the intersection. To their credit, Berkeley staff jumped into action. They quickly figured that the drainage design challenges are minimized by moving the bulb outs into the street. This move allowed them to maintain existing curb lines and drainage. Then, by moving the bike lane behind the bulb outs – abracadabra! – Berkeley created a protected intersection.

All bulb-out projects should be done this way.

berkeley_protected_inter

 

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Substandard cycletracks

The good news is that planners are finally embracing cycle-tracks. The bad news is that they are still designing substandard cycle-tracks.

A previous posting discussed a substandard cycle-track in Alameda. On the other side of the channel in Oakland, we find yet another example of half-assed bike infrastructure. Oakland bike planners are proposing to build cycle-tracks on Fruitvale Ave. The cycle-tracks would run from the BART station, under I880, and out towards the Bay. For the most part, the project is satisfactory — except for the segment running past I880. It is that segment which is by far the most dangerous for cyclists. And it is in that segment where the cycle-tracks would disappear entirely. Bicyclists would have no physical protection from the heavy traffic coming on and off the freeway.

Even worse, the plan would sandwich an unprotected bike lane between a right-turn lane and through traffic. This is a proven failure, as demonstrated most spectacularly last week in San Francisco.

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fruitvale2

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Last year, the Tampa Bay Times published a story on the racial disparities in police enforcement of black bicyclists. The article alleged that the Tampa Police had, in effect, a stop-and-frisk policy of black bicyclists. They called it the bicycle blitzkrieg, and 8 out of 10 people ticketed were black.

As a result of that report, the US Dept. of Justice conducted an investigation. The results were just published, which can read at http://ric-zai-inc.com/Publications/cops-w0801-pub.pdf.

The report confirms the allegations. The police department did have a policy of targeting cyclists in high-crime neighborhoods. Although these neighborhoods are predominantly black, the report stresses that this does not mean the program was racially motivated.

The stated purpose of the bicycle blitzkrieg was to: 1. recover stolen bicycles, 2. reduce traffic accidents, and 3. “pro-actively” reduce crime. The program failed to achieve any of these goals. Hardly any stolen bikes were recovered. The areas targeted for blitzkrieg did not have high accident rates to begin with. And the program did not reduce crime levels.

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A new road was recently constructed in South Fremont. Kato Rd was extended to connect with Mission Blvd. It provides a direct route between the the Warm Springs commercial district with various office parks along I880.

But as you can see, non-motorized users are not permitted to use it:

kato

This road was actually built as part of the Warm Springs BART extension project. There are some alternate routes available, but they are less safe and (depending on where you are coming and going) more circuitous.

 

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