A question about the crash test videos

[jenny03]

I've noticed on most of them that the car seats/boosters installed seem like they are loose. I was wondering if they are using the non-ALR seatbelts, or if it is normal for a TIGHT car seat to do that upon impact? My daughter's seat is tethered and so tight that you can't budge it. I can't imagine it being able to move that much. :( It makes me want to harness the other 2 kids, but they only have another year or so in the booster. :( We do use the ALR retractors on the boosters, too.

[jenny03]

I mean like this one:
http://www.oeamtc.at/netautor/html_seiten/kisitest_2002/videos/test2002/frontcrash/maxicosirodi.mpg

[papooses]

They are installed correctly & they do compare tethered vs. untethered :) I don't have any links to this, but in the U.S. untethered carseats must meet a head excursion limit of 32" while the tethered carseat has a 28" head excursion limit....

Seatbelts stretch in crashes (a dummy weighing about 30# in a 30MPH crash puts about 900# of force on the seatbelt) -- that's why it looks like there's so much movement.... So, when you replace your carseats after a crash, you should also have your vehicle seatbelts replaced :o

P.S. that video is a great example of why to use a seat that harnesses past the minimum 40# ;)

[jen_nah]

It also does't look like the harnessed seat is using top tether. I also don't think these crash videos are US crash testing. But, They are installed properly.

[scatterbunny]

They aren't US testing, but the two videos I use to compare harnessed vs. booster are seats that are/were sold in the US (the Maxi Cosi Priori and the Rodi--the Rodi is basically a TurboBooster). The speed is approximately 30 mph, so comparable to our crash testing speed, I believe. I'm sure there are differences, but unfortunately we aren't privy to most of the US carseat testing videos. :(

[papooses]

Right, the link above is German ... I wasn't really clear in my original response -- sorry ... they're all installed correctly for testing, according to each country's testing purposes -- not sure what the German requirements are, but no, they're not tethered in the videos we have -- I did already state the American requirements above ... it would be really quite lovely if we could have public access to the American testing :rolleyes: :o :)

[joolsplus3]

I've noticed on most of them that the car seats/boosters installed seem like they are loose. I was wondering if they are using the non-ALR seatbelts, or if it is normal for a TIGHT car seat to do that upon impact? My daughter's seat is tethered and so tight that you can't budge it. I can't imagine it being able to move that much. :( It makes me want to harness the other 2 kids, but they only have another year or so in the booster. :( We do use the ALR retractors on the boosters, too.

Those Austrian tests don't have top tethers or ALR belts...they have ELR belts and built in seatbelt lockoffs. But as the PP noted, there's a HUGE amount of belt stretch no matter what. I've seen crash tests of top tethered seats, and they look about the same as those OEAMTC tests... it's pretty scary looking. Also, think about the 'safe' head excursion allowances... 28 inches with a top tether and 32 inches without a top tether. Get out a measuring tape and measure from behind the seatback forward that far...it's pretty far. But the forward movement is not what causes injury, it's when the head strikes something in front of it that does (like jumping out of an airplane...it's not the falling that kills you, it's the landing). In a 30mph crash, a 30lb child suddenly weighs 900 pounds, virtually...so even though your seat feels tight when you pull on it, you aren't putting 900 pounds of force on it, and yes, it will move a LOT in a crash (but a lot less than if it's installed loosely and not top tethered and the harness is too loose, fortunately!).

:)