This holiday season, in the U.S. alone, 1,161 people will die in motor vehicle crashes, and 124,100 will be injured, many cripplingly and irreparably. Please don't be amongst them. (For my sake!) Please drive very carefully. Please review last year's harangue ("How To Not Die In A Car Crash"), for quick tips on the most important things you can do to stay alive on the road.
For this year's harangue, I'm publishing excerpts (which I've been meaning to do anyway) from a totally fascinating book I read last year, Traffic: Why We Drive the Way We Do (and What It Says About Us).
"I mostly look at individuals that get seriously damaged in the aftermath of a crash," [a doctor and traffic safety researcher] told me in his office. "For many of them, their lives are ruined forever. For many of them, there's also this tremendous sense of remorse or chagrin you know, if only they had behaved slightly differently, they would have never ended up in the hospital."
For those of us who aren't brain surgeons, driving is probably the most complex everyday thing we do. It is a skill that consists of at least 1,500 subskills. At any moment, we are navigating through terrain, scanning our environment for hazards and information, maintaining our position on the road, judging speed, making decisions (about 20 per mile, one study found), evaluating risk, adjusting instruments, anticipating the future actions of others even as we may be sipping a latte, thinking about last night's episode of American Idol, quieting a toddler, or checking voice mail… and then repeating the cycle, every minute you drive. (from Chapter Two: Why You're Not as Good a Driver as You Think You Are)
…driving, the most dangerous thing most of us will ever do.
We may be "unskilled and unaware of it"… a driver who is not fully aware of the risks of tailgating or the rules of traffic is hardly in a good position to evaluate their own relative risk or driving performance.
"As an average driver you can get away with a lot before it catches up to you. That's one of the problems. The feedback loops are not there. You can be a bad driver for years and never really realize it, because you don't get that demonstrated to you. You could drive for years with a cell phone and say, 'How can cell phones be dangerous, because I do it every day for two hours and nothing's happened?' Well, that's because you've been lucky." - head of the Cognitive Systems Lab at the University of Iowa
"I guarantee you that you've got driving habits you're not even aware of that are an accident waiting to happen." [- CEO of a company that installs small video cameras in cars which record the moments before and during accidents, near-accidents, and incidents of careless driving]
Not only was the driver [whose driving was video-recorded] unaware of the real hazards he was subjecting himself and others to in the way he was driving, he was not even aware that he was unaware. "I get reinforced more positively every day that I don't hit a kid because I'm not seeing that stuff [e.g. the kid by the edge of the road the driver never even saw]. I'm thinking I'm good, I can do this. I can look down at my BlackBerry, I can dial a phone, I can drink. We all get reinforced the wrong way."
Teenagers in Iowa, because of its agricultural character, can begin driving to school at fourteen. "That crash rate is absolutely out of sight," said [director of the Human Factors and Vehicle Safety Research Program at U. of Iowa].
As the sense of routine begins to take over, we begin to ratchet up our sense of the possible how close we can follow, how fast we can take curves and become conditioned to each new plateau.
Most driving rarely requires our full workload. So we listen to the radio, look out the window, or, increasingly, talk on the cell phone… But the problem with driving is that we never know for sure when things are going to change very quickly, when that nice empty road seemingly safe for a cell phone conversation is going to turn into an obstacle course. We may also be unaware of just how much workload our secondary activity is consuming.
"My basic belief after almost forty years of studying this stuff is that people can't [multi-task] at all," [a crash investigator and researcher at the University of Massachusetts] told me. "You only get the appearance."
As the inner life of the driver begins to come into focus, it is becoming clear not only that distraction is the single biggest problem on the road but that we have little concept of just how distracted we are.
In the largest study to date of the way we actually drive today, it was found that almost 80 percent of crashes and 65 percent of near crashes involved drivers who were not paying attention to traffic for up to three seconds before the event. That period of time is critical. "A total time of two seconds looking away from the forward roadway is when people start to get in trouble," explained [the study's project manager]. The point is that a lot can happen in two seconds like colliding with the car in front if it came to a stop or slowed but drivers, lulled by the expectancy that it will not stop, drive as if the world will not have changed when they return their eyes to the road.
"Cell phone conversations are particularly insidious because you don't notice your bad performance, particularly on the cognitive side," [guy cited earlier] argues.
Studies consistently show intersections to be one of the most dangerous places for cyclists (not to mention other cars) in traffic… Intersections are crash magnets in the U.S., 50% of all road crashes occur at intersections. At a four-way intersection, there area staggering 56 potential points of what engineers call "conflict," or the chance for you to run into someone 32 for vehicles to hit other vehicles, and 24 where vehicles can hit pedestrians.
Engineers call the moment when we're too close to the amber light to stop and yet too far to make it through without catching some of the red phase the "dilemma" zone. And a dilemma it is. Judging by crash rates, more drivers are struck from the rear when they try to stop for the light, but more serious crashes occur when drivers proceed and are hit broadside by a car entering the intersection.
Traffic lights have pernicious effects in and of themselves… The desire to "catch" a green makes drivers speed up at precisely the moment they should be looking for vehicles making oncoming turns or entering the main road from a right turn on red. The high placement of traffic lights also puts drivers' eyes upward, away from the street and things like the brake lights of the slowing cars they are about to hit.
Rumble strips are an element of what has been called "the forgiving road." The idea is that roads should be designed with the thought that people will make a mistake. "When that happens it shouldn't carry a death sentence," as [the head of the European Road Assessment Programme] explained it to me. "You wouldn't allow it in a factory, you wouldn't allow it in the air. We do allow it on the roads."
People do drive like idiots. Traffic makes it hard for us to be human. Drivers, insulated in their anonymous cocoons and holding a 3000-pound advantage, kill hundreds of pedestrians every day around the world.
More pedestrians are killed by cars in New York City than anywhere else in the U.S. But as the number of pedestrians or cyclists increases, the fatality rates per capita begin to drop.
Surely the urban pedestrian "Walk" signal must be vital to the safety of people on foot? Yes, except that at most intersections it happens to accompany the invitation for drivers to make a turn. The result is that every year, many pedestrians, correctly believing themselves to have the right-of-way, are killed while walking in the crosswalk by perfectly sober drivers who have paid slavish attention only to their own green light… The sad fact is that more urban pedestrians are killed while legally crossing in crosswalks than while jaywalking.
Distance, like speed, is something we often judge rather imperfectly. Unfortunately for us, driving is really all about distance and speed. Consider a common and hazardous maneuver in driving: overtaking a car on a two-lane road as another approaches in the oncoming lane. When two objects like cars are within 20 or 30 feet, we're good at estimating how far away they are, thanks to our binocular vision. Beyond that distance, both eyes are seeing the same view in parallel, and so things get a bit hazy. The farther out we go, the worse it gets: For a car that is twenty feet away, we might be accurate to within a few feet, but when it is 300 yards away, we might be off by 100 yards.
Viewing a car head-on or directly from behind, as we almost universally do, is like viewing a baseball hit right at you: It doesn't give you a lot to go on. We can tell the car is getting closer but we have no idea of the rate at which it is getting closer.
A car in the distance approaching at 20mph makes passing easy, but what if it is doing 80mph? The problem is this: We cannot really tell the difference.
People think small cars are farther away than they really are… Large objects often seem to move more slowly than small objects… The problem with visual illusions is that we fall for them even when we know they are illusions.
This is what happens when we drive at night. We think we can see better than we actually can and we drive accordingly. We "overdrive" our headlights… We are blind to our blindness. Remember this the next time you are out walking. Studies have shown that pedestrians think drivers can see them up to twice as far away as drivers actually do.
When fog rolls in on a highway, the result is often a huge, multicar chain-reaction crash. Obviously, it is harder to see in a fog. But the real problem may be that it is even more difficult to see than we think it is. The reason is that our perception of speed is affected by contrast. The higher the contrast, the faster the apparent motion. In fog, contrast of cars, not to mention the surrounding landscape, is reduced. Everything around us appears to be moving more slowly than it is, and we seem to be moving more slowly through the landscape. Similar things happen in the whiteout conditions of snow.
"Objects in mirror are more complicated than they appear." The same could be said of driving, as well as our ability to drive, and probably us too. It is all more complicated than it appears. We would do well to drive accordingly.
The most important risk factor, one that is subtly implicated in all the others, is speed… In a crash at 50mph, you're 15 times more likely to die than in a crash at 25mph not twice as likely, as you might innocently expect. The relationships are not proportional but exponential.
Ride in the back seat. The fatality risk in the back seat is 26% lower than in the front. The back seat is safer than airbags.
[Bias in media attention] helps to explain why, in countries like the U.S., the annual death toll from car crashes does not elicit more attention. Tally the number of people who have been killed by terrorism and you'll get a total of less than 5,000 roughly the same number as those who have been struck by lightning. But each year, with some fluctuation, the number of people killed in car crashes in the U.S. tops 40,000. No further deaths due to terrorism have occurred in the U.S. since 9/11 even as more than 350,000 people have died on the roads… Why is there no outrage? Driving is voluntary, it's in our control, and there's a reward. And so we fail to recognize the real danger cars present. We have deemed the rewards of mobility worth the risk.
We all think we're better than average drivers. We think cars are the risk when on foot; we think pedestrians act dangerously when we're behind the wheel. We want safer cars so we can drive more dangerously. Driving, with its exhilarating speed and the boundless personal mobility it grants us, is strangely life-affirming but also, for most of us, the most deadly presence in our lives.
For obvious reasons, I've excerpted the bits about safety and the insidious dangers of driving. But this book also has a huge amount of fascinating material on traffic jams, commuting, suburbia, parking, urban planning, walking, cycling, traffic calming, mixed-use spaces, psychology, supply and demand of road capacity (and parking!), Nash equilibria and tragedies of the commons, the uninternalized externalities of driving, the social impacts, the paradoxical effects of too many road signs and rules, fuel taxes, road engineering, how traffic reports affect traffic (the "self-destroying prognosis"), the safety advantages of roundabouts, why dangerous roads are safer, risk homeostasis, Scandinavian vs. Roman drivers, income-adjusted speeding tickets, and technology solutions for preventing road crash fatalities.