What is the purpose of a seatbelt pretensioner?

Author's Note

Between saves by motorcycle helmets and seat belts in assorted vehicle mishaps, I'm probably on my fifth or sixth life in cat terms. So learning for this article about the various ways one can "buy the farm" (or just lease it, if you get off with mere paralysis) by forgetting to wear a seatbelt held, well, a certain macabre fascination for me. It also prompted a less creepy thought: How cool is it that the same pretensioner concept used in combat plane ejection seats protects civvies in their cars, as well? Countless auto accident survivors literally owe their lives to a handful of inventors who enhanced the seatbelt into an active restraining device, by developing the seatbelt pretensioner. I confess to having some mixed feelings about the ongoing nannyfication of car technology; but on balance, the seatbelt pretensioner seems like a benign and relatively non-intrusive safety feature. And hey, if it lets you cheat the grim reaper, even if just for now, what's not to like?

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  • Centers for Disease Control. "Seat Belts Fact Sheet." (April 2, 2012) http:/ /www.cdc.gov/motorvehiclesafety/seatbelts/facts.html
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