dombey

ok guys explain something to me.

Rear-facing car seats for kids. Why does this make sense?
here is my train of thought:

-front facing or rear facing, it only matters in a collision where one car hits the back of another, or in a head-on. Correct?
-of these two types, there aren't a lot of head-on collisions. the vast majority are front-hits-back.
-in a front-hits-back, you theoretically have no say in whether you're the hitter or the since no one WANTS to have an accident
-as the hitter, you'd prefer a rear-facing seat; but as the hittee, you'd prefer a front-facing seat.
-The energy involved on either side should be the same

so why does everyone make such a big deal out of rear-facing seats if there isn't much of a practical purpose? Is the ONLY reason because in a head-on the kid is better off?
I would think that if you're getting that far into the tail of auto crashes, you'd be willing to maybe follow cars at a longer distance, virtually eliminating your chance of being the hitter, and buying a forward-facing seat to protect against rear end collisions, and take your chances on the head-on.

it sounds like marketing to me.

rockville

So we can assume that your odds of getting hit from behind are equal to your odds of hitting someone from behind (this is a HUGE assumption). Let's also assume that the best thing for the child is to have the back of the head in a seat back during the impact. Thus if we are going to hit someone we want the seat facing backwards. If we are going to get rear ended we want the child facing forward. So far we have no preference. Next would be which impact on average subjects the occupants to higher accelerations. I have no idea. Again we call it a draw.

What about single car or T-bone wrecks? Some runs a red and you T-bone them. No idea how common these are or someone runs you off the road and you hit a stationary object. Again no idea what percent of crashes this represents. However, I think we can safely assume these are almost always forward facing wrecks. So that would have us preferring rear facing safety seats.

Finally, what if we get hit from the side? In this case I see no advantage as either side hit will be to the side of the seat. So I would say we want rear facing due to single car and T-bone type wrecks.

Incidentally I thought the guys who wrote Freakonomics had a really interesting take on car seats. While, according to them, the seatbelt is the single most cost effective modern safety device in terms of $ per life saved (something like $23k/life) seats for children over the age of 4 (I think it was 4) get basically no benefit for riding in a booster seat. They did crash testing with child dummies in rear seats of cars and said that if they submitted the data to the NHTFA the rear seat+ seatbelt would have passed with flying colors. Other data was presented but I no longer remember all the details. They use the toddler seat as an example of a good idea taken too far.

cbehney

It could also be that accidents are rare but hard braking is much more common, and having the kid rear facing puts less stress on the weak necks of kids. Just speculating.

dombey

personal driving habits aside, I don't see how your odds are different between hitting someone from behind or being hit from behind. it takes two.

I see your point on t-bones and whatever. I'd be interested to see if there was really any data suggesting a rear facing is better in a t-bone wreck...in reality and not in a lab. I'm skeptical because there are rarely "perfect" t-bones. usually some last second steering input to avoid the wreck, imperfect alignment on impact, all sorts of twisting and what not as a result, kid might be in a compromising position to start because of the steering corrections, etc... I have no doubt that in a lab it is better but in practice I wonder.

rockville

Unless oil leaking from a valve cover gasket gets on the front tires...
oh wait, wrong thread.

rockville

That was pretty much my thought as well. For every rear ender I expect one car to to smash it's nose and one to have a smashed tail thus I feel that for any rearend accident we can't form a preference ASSUMING we know the forces are equal on both cars. So if one car is stopped and the other car rear ends the first then we assume the forces on each set of occupants are equal. In theory if the stationary car was facing backwards we would see equal damage in both.

I would agree that perfect T-bones are probably rare but remember in basically all T-bone cases your body will move at least partially forward. A T-bone is likely to cause you to slow and spin. Rarely would it cause you to accelerate (ie get pushed back into the seat).

dombey

no doubt about that; I just wonder what that does to the survivability in a car seat...if the kid's neck is the problem, it seems a combo of sideways/spinning and rapid deceleration would be terrible even if they were in the rear facing seat. I guess it is a matter of being "less bad"....

rockville

I think the problem is the rotation is bad but doesn't change in a rear or front facing seat. We only get the choice of better protecting the neck for loads along the length of the car in the forward or rearward direction (ie the body wants to keep going generally forward or generally backwards). Of course our assumptions were made without crash data.

NuncoStr8

I was thinking similar to this. It's not "in case of accident," it's in case of regular driving.

s2kpdx01

something i found:
I think rear facing is safest for everyone including adults, but more so for children with developing spinal columns.
claim:
take it for what's it worth.