The second day of the 2011 Michigan Traffic Safety Summit began and ended with seemly conflicting data regarding the distracting influence of our pal the cell phone. That goes for both car divers and commercial vehicle drivers. So, I can now confidently tell you that your cell phone conversation is either extremely distracting or not any more dangerous than many of the more secondary distractions in the vehicle. Right, so what the heck does that mean? It means that I’ll do a more complete explanation of this issue next week. For now, here are my notes from Summit day two.
Oh, by the way: there seems to be no conflict whatsoever regarding the danger of texting while driving. It’s right on the top of the dangerous activities list. OK, back to the notes:
The estimate is that there are one million crashes per year that can be related to cell phone use in some way. A survey shows that 81% of us admit that we text while driving.
Multitasking is something that we seem to value culturally. We equate it to productivity, and is most likely a skill that many of us list on our resumes. However, studies of how the brain works demonstrate that multitasking is a myth. The brain does not multitask. The brain, within its limited range of processing power, handles tasks in a sequence. Also, this sequential processing of tasks calls on many different areas within the brain. So, even though the tasks are handled quickly, they are handled one at a time.
People that are proud to call themselves heavy multitaskers most often are taking more time to complete the individual tasks and are making more errors. When you switch from one task to another, your brain must reorient. This switching of orientation equates to fractions of a second that add up during the completion of multiple tasks.
Since we have this finite (limited) processing power available in our brains, when we multitask in the car our brains must filter out stuff so that enough processing power remains to handle all of the tasks. Some valuable ques that often find themselves filtered out include red lights, brake lights, navigation signs, obstructions, changes in the roadway surface, pedestrians, items entering the roadway and others. We look at them, but do not see them.
Items have to be seen or heard before they can be encoded into short-term memory. If they don’t make it to short-term memory they are not available to the brain for processing. So, we miss stuff either because we’re looking somewhere else, or because our brains are filtering it out. Either way, if we can’t process it we can’t act on it. One big problem is that we do not know the physical limits of our brain’s processing capacity, and it does not warn us. We can easily gauge our physical capacities such as how far we can run or how much weight we can lift, but our brain’s processing capacity is not similarly visible to us. So, we simply do not know when we are pushing the physical limits of our brain.
The challenges to response time and processing capacity are also perils for pedestrians. Urban walking is a cognitively demanding task. We’ve seen this challenge manifested by walkers obliviously crossing busy streets, colliding with other walkers or smacking into poles. In some locations, commonly smacked poles have had a protective foam barrier placed around them.
Further information about this multitasking issue can be found at the National Safety Council site at HTTP://thebrain.nsc.org
The Federal Motor Carrier Safety Administration (FMCSA) has established a new Compliance, Safety and Accountability (CSA) system for tracking and evaluating the safety performance of US commercial truck and bus companies. Using roadside surveys, this Safety Management System (SMS) measures driver and company compliance based on seven parameters that include driver fatigue (hours of service), driver fitness, seatbelts, drug/alcohol, maintenance, cargo related, and prior crash indicators.
An intervention is triggered by poor performance data over a two-month interval. Businesses are grouped on the basis of how they compare to other US businesses that provide a similar level of service. (# of vehicles, miles driven, drivers, etc.). These SMS scores are available to both the companies and the public, and so they can be used when someone considers hiring a particular carrier to transport their goods or children. There are 730 Michigan based carriers that will be getting a warning letter in the first batch to be issued (26,000 nationally).
The FMCSA also now provides a pre-employment screening program that maintains two years of data related to commercial drivers. This is available for companies to use when making hiring decisions. Driver profiles are only released with their authority, and each search is $10.
There are now at least two new naturalistic studies of distracted driving among commercial truck and bus drivers. A naturalistic study is one where actual drivers are monitored by video cameras within their vehicles as they drive every day for many months or years. Metrics of vehicle reaction and performance are also captured at the same time. These are the only studies that document the exact activities and real world circumstances while a driver is operating within the highway transportation environment, and so they are extremely useful. At the same time, we are documenting the driver, the vehicle, the infrastructure and the environment. We’re doing these studies because, if we are currently having 33,000 deaths within the highway transportation system yearly, then we can certainly say that this system is not working. These studies seem to indicate that, when it comes to driving, vision is king.
These two large studies looked at 4,400 Safety Critical Events that took place while drivers were monitored. These included 21 crashes, 197 near-crashes, 3,019 crash-relevant conflicts and 1,215 unintentional lane deviations (translate that to: crossed the center line or ran off of the road). They looked at things like reaching, texting, dispatching, CB talking, phone talking, etc. The most dangerous activities were the ones that actually took the driver’s eyes off of the driving environment (if you don’t see it, you can’t process it). One study showed that texting in a commercial vehicle made the driver 2,300 times more likely to have a crash. That was followed by dispatching within the vehicle, writing in notebooks, using a calculator or looking at a map.
What these studies and a similar 100-car study seemed to document, though, was the comparatively lower risk that cell phone talking (particularly hands-free) posed. In the 100-car study, for example, the #1 issue was reaching for an object, followed closely by swatting at an insect. In both examples, it is the visual distraction that presents the issue relating to the crash. When eyes are off of the road for two seconds the risk of a crash is doubled. In one video taken from the 1000-car study you can clearly see the driver looking down briefly at their phone to dial it, and when they look back up there is a child on a tricycle in front of them. They have just enough time to stop.
Again, the studies would seem to indicate that vision is king, and that education along with enforcement will probably not be enough. The activities that take our eyes off of the road are the most dangerous. New technology is on the way to provide the driver with more help in detecting dangers within their operating environment. Devices will measure the distance and closing speeds between other vehicles or barriers. They will also measure how the driver is performing (are their eyes open).
Cell phone subscriptions have risen dramatically during the same period when we have seen a decrease in crashes (per vehicle miles traveled), and these new studies seem to be challenging our long-standing contention that the actual cognitive powers associated with the phone conversation are the real issue. For years we have said that hands-free is just as dangerous as any other kind of cell phone conversation while driving. Is this no longer the case? I’ll address the issues leading up to both of these theories in the next post.
Be Safe.
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