RearFacingAdvocate
New member
Okay, I have been all over thes forum in the past few days and it seems to me that there are varying "understandings" and "opinions" on this topic. I wanted a straight answer, so I went to the source.
Here is what Sunshine Kids has to say on why it's okay to go to 51" tall (or until the top of the ears reach the top of the seat) on the Radians. For those of you with older models, (or who have read the height limit to be 49" somewhere, please note that after further testing was done, Sunshine Kids released the 51" or top of ears rule on ALL Radians, reguardless of manufacture date. They didn't change the seats, just did more testing.):
" I understand that no other car seat allows this [shoulders above top slots FF], but Radian is like no other car seat. Radian has a unique structure and different seated positioning for the child than other convertible car seats. Radian65 is the strongest car seat in its class and (to our knowledge) Radian80 is the strongest car seat in the world.
Radian’s unique design and incredible strength allow it to do what no other seat can: Permit a child’s shoulders to go above the top harness slots as long as the child’s ears are below the top of Radian’s seat back. While there will be some very tall 65 lb kids for whom this will make a difference, more practically it is focused towards the Radian80 to allow the highest percentage of larger and older kids to still be able to take advantage of Radian80's harnessed capacity and yet continue to maintain an overall height that allows the flexibility of rear-facing.
...Simply put, Both Radian65 and Radian80 were crash tested with large size dummies whose shoulders were above the top harness positions. In crash testing, both Radian65 and Radian80 met all the biomechanical values established by NHTSA – standards which Radian is not even required to meet for such a large child occupant.
The dummies used for crash testing (whose shoulders are above the top harness slots) were fully instrumented to record loads in all 3 vectors of movement: X, Y and Z (ie. fore-aft, horizontal and vertical). The numerical values recorded during crash testing show that the biomechanical loads experienced by the dummy in each of these three vectors. Results of these crash test showed that all the biomechanical values were all well below those values established by NHTSA in FMVSS213.
What this means is that even with the child’s shoulders above the top slots, Radian’s vertical chest loading (Z- vector) was sufficiently low enough (ie. well within NHTSA’s values) to demonstrate conclusively that there is no excessive spinal loading.
And remember, NHTSA does not even set any limits for biomechanical values for children above 50 lbs – perhaps because such limits were deemed too difficult to meet for traditional car seat designs? Currently, to ‘pass’ crash testing for an 80 lb or even 65 lb child occupant the dummy must simply remain contained within the restraint and that restraint cannot break. That’s it. That’s all that is required by law. Sunshine Kids is committed to providing safety and performance well beyond what is required by NHTSA in terms of strength, safety and performance.
...Again, this does NOT mean you can do this with other seats. Radian is an exceptionally strong seat, has a low center of gravity. There is a reason other seats do not allow shoulders above the harness slots, and there is a reason why Radian can.
...51” standing height is a good rule of thumb for Radian…because standing height of a child is what people know, not seated height. But really the limitation is the seated height: As long as the tops of the ears are below the top of Radian’s seat back, then the child is within the correct height for Radian."
Again, that was all quoted verbatum from an email from Sunshine Kids. (With permission to post, of course.) With this new info, please vote on poll.
Stephanie
Here is what Sunshine Kids has to say on why it's okay to go to 51" tall (or until the top of the ears reach the top of the seat) on the Radians. For those of you with older models, (or who have read the height limit to be 49" somewhere, please note that after further testing was done, Sunshine Kids released the 51" or top of ears rule on ALL Radians, reguardless of manufacture date. They didn't change the seats, just did more testing.):
" I understand that no other car seat allows this [shoulders above top slots FF], but Radian is like no other car seat. Radian has a unique structure and different seated positioning for the child than other convertible car seats. Radian65 is the strongest car seat in its class and (to our knowledge) Radian80 is the strongest car seat in the world.
Radian’s unique design and incredible strength allow it to do what no other seat can: Permit a child’s shoulders to go above the top harness slots as long as the child’s ears are below the top of Radian’s seat back. While there will be some very tall 65 lb kids for whom this will make a difference, more practically it is focused towards the Radian80 to allow the highest percentage of larger and older kids to still be able to take advantage of Radian80's harnessed capacity and yet continue to maintain an overall height that allows the flexibility of rear-facing.
...Simply put, Both Radian65 and Radian80 were crash tested with large size dummies whose shoulders were above the top harness positions. In crash testing, both Radian65 and Radian80 met all the biomechanical values established by NHTSA – standards which Radian is not even required to meet for such a large child occupant.
The dummies used for crash testing (whose shoulders are above the top harness slots) were fully instrumented to record loads in all 3 vectors of movement: X, Y and Z (ie. fore-aft, horizontal and vertical). The numerical values recorded during crash testing show that the biomechanical loads experienced by the dummy in each of these three vectors. Results of these crash test showed that all the biomechanical values were all well below those values established by NHTSA in FMVSS213.
What this means is that even with the child’s shoulders above the top slots, Radian’s vertical chest loading (Z- vector) was sufficiently low enough (ie. well within NHTSA’s values) to demonstrate conclusively that there is no excessive spinal loading.
And remember, NHTSA does not even set any limits for biomechanical values for children above 50 lbs – perhaps because such limits were deemed too difficult to meet for traditional car seat designs? Currently, to ‘pass’ crash testing for an 80 lb or even 65 lb child occupant the dummy must simply remain contained within the restraint and that restraint cannot break. That’s it. That’s all that is required by law. Sunshine Kids is committed to providing safety and performance well beyond what is required by NHTSA in terms of strength, safety and performance.
...Again, this does NOT mean you can do this with other seats. Radian is an exceptionally strong seat, has a low center of gravity. There is a reason other seats do not allow shoulders above the harness slots, and there is a reason why Radian can.
...51” standing height is a good rule of thumb for Radian…because standing height of a child is what people know, not seated height. But really the limitation is the seated height: As long as the tops of the ears are below the top of Radian’s seat back, then the child is within the correct height for Radian."
Again, that was all quoted verbatum from an email from Sunshine Kids. (With permission to post, of course.) With this new info, please vote on poll.
Stephanie