Aug 17 2010
Archive for the 'safety' Category
Aug 02 2010
Episode 33 - Safety: A Brief Disposition
Feb 01 2010
Episode 31 - Toyota Recall and Safety
Apr 08 2009
NHTSA Announces Preliminary 2008 Fatality Analysis
The National Highway Traffic Safety Administration (NHTSA - pronounced nit’ suh) announced the preliminary 2008 statistics for Fatal Crashes in the United States (report, pdf). According to projections, traffic fatalities fell to 37,313, down from 41,059 in 2007. That is excellent news!
Similarly the fatality rate fell to 1.28 from 1.36. This rate is measured in fatalities per 100 million vehicle miles traveled, and as I’m sure you’re aware from the news media (and my humble services here) vehicle miles traveled also fell last year.
The reduction in fatalities is being reported as correlated with increased seat belt use across the nation. Everyone is careful to not actually state that seat belt use is fixing the problem, but in this case I’m willing to give them a pass for using statistics to lie to you. It is highly probable that increased seat belt use is a causal factor1 in the reduction of fatal crashes but it is a difficult supposition to prove. Other factors that may be causing fatalities to drop is reduced response time for medial personnel2, increased use of graduated drivers licenses for teens and/or safer vehicles.
1: See “Correlation does not imply causation”
2: See Golden Hour
Apr 06 2009
I-75 HOV Exit Problem
You may recall from March 2007 the Bluffton University baseball team bus that mistakenly exited the interstate in Atlanta on a left-hand ramp, failed to recognize the stop condition at the top of the ramp and crashed through the barrier wall on the opposite side of the cross road, falling to the interstate and killing seven.
It has happened again, thankfully without any crashes or injuries. A bus driver thought that the left-hand exit was a continuation of the through lane and took the ramp, but the increased signage, striping and raised reflective pavement markers brought to his attention that he should stop.
The question here is, what to do? You might think from that AJC story I linked that the Georgia Dept. of Transportation is being lackadaisical about this problem, but I assure you they are not! I don’t have any good before/after images of the exit ramp signage and striping but if you were familiar with the road, you’d realize that it was a night and day difference. And there is a project in the works to put in large overhead guidesigns at all of the HOV exits around town.
Yet despite the extremely over-signed-and-marked left-hand exit at Northside Drive, another bus driver made the same mistake. Why?
From my own experience driving that stretch of HOV lane, it’s easy to see how you might do it. The road is in a slight left turn at that location and if you are following the left edgeline, you might just drift into the exit lane and proceed up the ramp. GDOT has used a dotted white stripe to indicate that the edgeline continues across the ramp exit, but I can still see how the mistake might be made.
However, let’s not forget that despite the driver error in this case, the signage was sufficient to alert him to the dangerous condition and the bus was stopped safely at the stop sign. I think that’s a win, don’t you?
171,000 vehicles per day passed this spot in 2007, according to GDOT’s coverage traffic counts. Extrapolating that to today means 124 million vehicles have gone through. Using some guesses of 0.5% bus traffic and perhaps a third of those using the HOV lane, that means 208,000 buses have passed this exit and only two (that we know of) have incorrectly evaluated the situation. That’s 0.0009 percent of the buses making a bad call.
Could this ramp have been designed better? You betcha! Are signs and striping going to “solve” the problem? Probably not. Unless you define the problem as “keep people from dying by driving over the top of Northside drive bridge thinking it’s I-75″. That I think is already solved. If you define the problem as “keep people from taking this ramp, thinking it’s I-75″ then I expect to hear of more cases in the future.
Aug 18 2008
Episode 24 - National Traffic Signal Report Card
Topics: National Traffic Signal Report Card, 2007 Fataliity Rates, ITE Annual Meeting
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Apr 24 2008
Traffic Tidbits: 24 April 2008
It’s been a while since my last tidbits post. Let’s try to make this a good one!
Laser walls!: Laser walls for visual cueing of the car/pedestrian interface and trying to make it safer for pedestrians in urban areas. It’s interesting.
Canadian Airspace for American Airliners: When flights heading to NY Laguardia or Newark or Kennedy amble into harsh weather, there’s not a lot of room to stack them up, or to avoid the strong winds and thunderstorms. A plan may be in place to allow these airliners to cross Canadian airspace to find favorable conditions. This is also apparently running into Homeland Security roadblocks from a quid pro quo perspective.
Passenger & Freight Rail UP while Air Transport DOWN?: Some discussion about the future of transportation and how it’s affecting the rail and air industries.
Sao Paulo has Bad Traffic: Check out this TIME article about Sau Paulo and its commuters
Wired Photo Contest: Wired magazine is having a transportation themed photo contest.
Apr 22 2008
Episode 20 - The Aging Population
Mar 24 2008
Episode 17 - Red Light Enforcement, Red Light Running, Clearance Intervals
Topics: Red Light Enforcement, Red Light Running, Clearance Intervals
Episode 17 - Red Light Enforcement, Red Light Running, Clearance Intervals [10:35m]: Play Now | Play in Popup | DownloadContinue Reading »
