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How to avoid dying in a car crash

76 michaelcurzi 17 March 2012 07:44PM

Aside from cryonics and eating better, what else can we do to live long lives?

Using this tool, I looked up the risks of death for my demographic group. As a 15-24 year old male in the United States, the most likely cause of my death is a traffic accident; and so I’m taking steps to avoid that. Below I have included the results of my research as well as the actions I will take to implement my findings. Perhaps my research can help you as well.1

Before diving into the results, I will note that this data took me one hour to collect. It’s definitely not comprehensive, and I know that working together, we can do much better. So if you have other resources or data-backed recommendations on how to avoid dying in a traffic accident, leave a comment below and I’ll update this post.

General points

Changing your behavior can reduce your risk of death in a car crash. A 1985 report on British and American crash data discovered that driver error, intoxication and other human factors contribute wholly or partly to about 93% of crashes.” Other drivers’ behavior matters too, of course, but you might as well optimize your own.2

Secondly, overconfidence appears to be a large factor in peoples’ thinking about traffic safety. A speaker for the National Highway Traffic Safety Association (NHTSA) stated that “Ninety-five percent of crashes are caused by human error… but 75% of drivers say they're more careful than most other drivers. Less extreme evidence for overconfidence about driving is presented here.

One possible cause for this was suggested by the Transport Research Laboratory, which explains that “...the feeling of being confident in more and more challenging situations is experienced as evidence of driving ability, and that 'proven' ability reinforces the feelings of confidence. Confidence feeds itself and grows unchecked until something happens – a near-miss or an accident.”

So if you’re tempted to use this post as an opportunity to feel superior to other drivers, remember: you’re probably overconfident too! Don’t just humbly confess your imperfections – change your behavior.

Top causes of accidents

Distraction

Driver distraction is one of the largest causes of traffic accident deaths. The Director of Traffic Safety at the American Automobile Association stated that "The research tells us that somewhere between 25-50 percent of all motor vehicle crashes in this country really have driver distraction as their root cause." The NHTSA reports the number as 16%.

If we are to reduce distractions while driving, we ought to identify which distractors are the worst. One is cell phone use. My solution: Don’t make calls in the car, and turn off your phone’s sound so that you aren’t tempted.

I brainstormed other major distractors and thought of ways to reduce their distracting effects.

Distractor: Looking at directions on my phone as I drive

  • Solution: Download a great turn-by-turn navigation app (recommendations are welcome).
  • Solution: Buy a GPS.

Distractor: Texting, Facebook, slowing down to gawk at an accident, looking at scenery

  • Solution [For System 2]: Consciously accept that texting (Facebook, gawking, scenery) causes accidents.
  • Solution [For System 1]: Once a week, vividly and emotionally imagine texting (using Facebook, gawking at an accident) and then crashing & dying.
  • Solution: Turn off your phone’s sound while driving, so you won’t answer texts.

Distractor: Fatigue

  • Solution [For System 2]: Ask yourself if you’re tired before you plan to get in the car. Use Anki or a weekly review list to remember the association.
  • Solution [For System 1]: Once a week, vividly and emotionally imagine dozing off while driving and then dying.

Distractor: Other passengers

  • Solution: Develop an identity as someone who drives safely and thinks it’s low status to be distracting in the car. Achieve this by meditating on the commitment, writing a journal entry about it, using Anki, or saying it every day when you wake up in the morning.
  • Solution [In the moment]: Tell people to chill out while you’re driving. Mentally simulate doing this ahead of time, so you don’t hesitate to do it when it matters.

Distractor: Adjusting the radio

  • Solution: If avoiding using the car radio is unrealistic, minimize your interaction with it by only using the hotkey buttons rather than manually searching through channels.
  • Solution: If you’re constantly tempted to change the channel (like I am), buy an iPod cable so you can listen to your own music and set playlists that you like, so you won't constantly want to change the song.

A last interesting fact about distraction, from Wikipedia:

Recent research conducted by British scientists suggests that music can also have an effect [on driving]; classical music is considered to be calming, yet too much could relax the driver to a condition of distraction. On the other hand, hard rock may encourage the driver to step on the acceleration pedal, thus creating a potentially dangerous situation on the road.

Speeding

The Road and Traffic Authority of New South Wales claims that “speeding… is a factor in about 40 percent of road deaths.” Data from the NHTSA puts the number at 30%.

Speeding also increases the severity of crashes; “in a 60 km/h speed limit area, the risk of involvement in a casualty crash doubles with each 5 km/h increase in travelling speed above 60 km/h.

Stop. Think about that for a second. I’ll convert it to the Imperial system for my fellow Americans: in a [37.3 mph] speed limit area, the risk of involvement in a casualty crash doubles with each [3.1 mph] increase in travelling speed above [37.3 mph].” Remember that next time you drive a 'mere' 5 mph over the limit.

Equally shocking is this paragraph from the Freakonomics blog:

Kockelman et al. estimated that the difference between a crash on a 55 mph limit road and a crash on a 65 mph one means a 24 percent increase in the chances the accident will be fatal. Along with the higher incidence of crashes happening in the first place, a difference in limit between 55 and 65 adds up to a 28 percent increase in the overall fatality count.

Driving too slowly can be dangerous too. An NHTSA presentation cites two studies that found a U-shaped relationship between vehicle speed and crash incidence; thus “Crash rates were lowest for drivers traveling near the mean speed, and increased with deviations above and below the mean.”

However, driving fast is still far more dangerous than driving slowly. This relationship appears to be exponential, as you can see on the tenth slide of the presentation.

  • Solution: Watch this 30 second video for a vivid comparison of head-on crashes at 60 km/hr (37 mph) and 100 km/hr (60 mph). Imagine yourself in the car. Imagine your tearful friends and family. 
  • Solution: Develop an identity as someone who drives close to the speed limit, by meditating on the commitment, writing a journal entry about it, using Anki, or saying it every day when you wake up in the morning.

Driving conditions

Driving conditions are another source of driving risk.

One factor I discovered was the additional risk from driving at night. Nationwide, 49% of fatal crashes happen at night, with a fatality rate per mile of travel about three times as high as daytime hours. (Source)

  • Solution: make an explicit effort to avoid driving at night. Use Anki to remember this association.
  • Solution: Look at your schedule and see if you can change a recurring night-time drive to the daytime.

Berkeley research on 1.4 million fatal crashes found that “fatal crashes were 14% more likely to happen on the first snowy day of the season compared with subsequent ones.” The suggested hypothesis is that people take at least a day to recalibrate their driving behavior in light of new snow. 

  • Solution: make an explicit effort to avoid driving on the first snowy day after a sequence of non-snowy ones. Use Anki to remember this association.

Another valuable factoid: 77% of weather-related fatalities (and 75% of all crashes!) involve wet pavement.

Statistics are available for other weather-related issues, but the data I found wasn’t adjusted for the relative frequencies of various weather conditions. That’s problematic; it might be that fog, for example, is horrendously dangerous compared to ice or slush, but it’s rarer and thus kills fewer people. I’m interested in looking at appropriately adjusted statistics. 

Other considerations

  • Teen drivers are apparently way worse at not dying in cars than older people. So if you’re a teenager, take the outside view and accept that you (not just ‘other dumb teenagers’) may need to take particular care when driving. Relevant information about teen driving is available here.

  • Alcohol use appeared so often during my research that I didn’t even bother including stats about it. Likewise for wearing a seatbelt.

  • Since I’m not in the market for a car, I didn’t look into vehicle choice as a way to decrease personal existential risk. But I do expect this to be relevant to increasing driving safety.

  • “The most dangerous month, it turns out, is August, and Saturday the most dangerous day, according to the National Highway Traffic Safety Administration.” I couldn’t tell whether this was because of increased amount of driving or an increased rate of crashes.

  • This site recommends driving with your hands at 9 and 3 for increased control. The same site claims that “Most highway accidents occur in the left lane” because the other lanes have “more ‘escape routes’ should a problem suddenly arise that requires you to quickly change lanes”, but I found no citation for the claim.

  • Bad driver behavior appears to significantly increase the risk of death in an accident, so: don't ride in car with people who drive badly or aggressively. I have a few friends with aggressive driving habits, and I’m planning to either a) tell them to drive more slowly when I’m in the car or b) stop riding in their cars.

Commenters' recommendations

I should note here that I have not personally verified anything posted below. Be sure to look at the original comment and do followup research before depending on these recommendations.

  • MartinB recommends taking a driving safety class every few years.

  • Dmytry suggests that bicycling may be good training for constantly keeping one's eyes on the road, though others argue that bicycling itself may be significantly more dangerous than driving anyway.

  • Various commenters suggested simply avoiding driving whenever possible. Living in a city with good public transportation is recommended.

  • David_Gerard recommends driving a bigger car with larger crumple zones (but not an SUV because they roll over). He also recommends avoiding motorcycles altogether and taking advanced driving courses.

  • Craig_Heldreth adds that everyone in the car should be buckled up, as even a single unbuckled passenger can collide with and kill other passengers in a crash. Even cargo as light as a laptop should be secured or put in the trunk.

  • JRMayne offers a list of recommendations that merit reading directly. DuncanS also offers a valuable list.

1All bolding in the data was added for emphasis by me.

2The report notes that "57% of crashes were due solely to driver factors, 27% to combined roadway and driver factors, 6% to combined vehicle and driver factors, 3% solely to roadway factors, 3% to combined roadway, driver, and vehicle factors, 2% solely to vehicle factors and 1% to combined roadway and vehicle factors.”