Photo: Mike BabcockIn the SuperFreakonomics chapter on cheap and simple solutions, we wrote:
And seat belts, at about $25 a pop, are one of the most cost-effective lifesaving devices ever invented. In a given year, it costs roughly $500 million to put them in every U.S. vehicle, which yields a rough estimate of $30,000 for every life saved. How does this compare with a far more complex safety feature like air bags? At an annual U.S. price of more than $4 billion, air bags cost about $1.8 million per life saved.*
A reader named Rich Merrill writes in with an interesting comment:
In the early 70′s I was employed at Ford, doing bumpers and air-bag (safety car) testing.? There is another factor that may need to be considered to get an accurate picture of air-bag effectiveness. In order to work well, the occupants must be belted into place.? The air bag doesn’t keep people in place, it just cushions them when they are flailing around at the peak of the impact. And, of course, there are secondary impacts that occur after the air bag has deflated, so belts are?also important for that “post-bag” event.
So, if the current seat belt usage is about 80%, there are 20% of the people riding around with less than optimal air-bag protection.? I’m not sure how you’d measure it, but this would raise the air bag statistics a bit.
Something you might want to put in future editions?
Note: I’m not a big air bag fan and I have no dog in this fight.? I’m a retired engineer (5 years) and left the auto business in 1975.? I agree completely with your comparative “dollars-per-life” analysis.? Simple solutions are just plain hard to “sell.”? Maybe because nobody is making a profit on them? (Pat-downs vs. $canners at airports?)
*See Levitt and Porter, “Sample Selection in the Estimation of Air Bag and Seat Belt Effectiveness,” The Review of Economics and Statistics 83, no. 4 (November 2001).
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Isn’t the government calculated value of a life for Regulatory purposes something around 2 million dollars? Just saying that something costs 1.8 million per life saved doesn’t allow a comparison unless you state the value of a human life. Last I recall this value was in the neighborhood of 1.5 to 2 million dollars so therefore air bags are right in line with what our government believes is a justified regulatory expenditure.
Compared with the new advanced train protection technology mandated in a 2008 law that threatens to cost hundreds of millions of dollars per life saved airbags are a downright bargain. Perhaps you should look into that instead.
I’ve always wondered why auto insurance rates didn’t go down when primary seat belt laws were enacted.
Funny how that worked…
wouldn’t this actually raise the seat belt stats as air-bags alone aren’t actually useful? I guess it depends on how you compute the lives saved by airbags, and which marginal you are going on.
If my life, or that of any of my family or friends, is saved, it is well worth the cost.
Do airbags reduce injuries and deaths among seatbelt-wearers? I’d like to see the numbers.
I regard airbags as a protective measure for people too stupid to wear a seatbelt. As such, airbags might well be a net financial loss to society even if they were a dollar each – but no-one, anywhere, ever got funding for a study of the economic benefits of culling the stupid.
I would relish being contradicted on this point.
I have never experienced the pleasure of having an airbag deploy, but I did once flip my pickup truck over on its side while driving on an icy road. Fortunately I had my safety belt on and was completely uninjured. A couple of passing motorists helped me push the vehicle back over. The impact had caused one tire to lose pressure, and there was a large dent in right front panel, but after changing the tire, I was able to continue my journey . I doubt I could have done that if there had been an airbag.
The purpose of an airbag is not actually to save vehicular occupants, but rather lessen any impact on them during the crash. So much trial and error, as well as chemical engineering goes into it that I am able to believe the large sum it must cost to produce. Effective or not, I ask myself, can this airbag and seatbelt “save” you from a crash coming from your side? Side crashes are very common especially in highways, and therefore, I am very concerned. Sometimes, the airbags have malfunctions and don’t open, how can the car companies prevent that? And finally, how effective are these security devices?
I often wonder, how much is an individual willing and able to pay for a sense of security.
-By actual observation, the severity and fataility rate goes up dramatically when passenger/drivers are “thrown clear”.
-By actual observation, seatbelt and airbag deployment together prevent many injuries and deaths from occurring.
-By actual observation widows/widowers/orphans and surviving family members of the disabled, along with the disabled themselves, face horrible burdens, emotional AND economic.
Once again the economists prove conclusively to know the cost of everything and the value of nothing.