Harness Strap Height - Where Do You Draw 'the Line'?

[shauburg]

I know the rules (at or below for RF, at or above for FF), but want to be sure I'm applying them consistently in real life.

When determining whether a child's harness straps are below, at, or above their shoulders, where do you draw the determination line? Do you draw it perpendicular (90° angle) to the seat back OR parallel to the ground?

Do you do it differently for RF vs FF? If so, why? How does where you draw the line for RF vs. FF affect the child's safety?

Do you do it differently for different seats? I have attached some pics from different manuals.

Thanks everyone!


Marathon - RF
http://www.car-seat.org/picture.php?albumid=14&pictureid=349

Marathon - FF (Indicates that line must be parallel to the ground)
http://www.car-seat.org/picture.php?albumid=14&pictureid=350

Radian
http://www.car-seat.org/picture.php?albumid=14&pictureid=351


True Fit (They obviously draw the line perpendicular to the seat back, because that red FF strap would not be considered at or above using Britax's line.)
http://www.car-seat.org/picture.php?albumid=14&pictureid=352

[QuassEE]

I think that often times it will depend on the seat and child more than anything. There are some cases where I've recommended parents move the harness height up with 1cm above the child's shoulders when RF due to the harness straps slipping or being SO far down the child's back that it was no longer safe (think Combi Connection)... I personally would rather err on the side of always aiming for going slightly above versus extremely or slightly below for RF and FF. Why?

RF--My rationale stems from the fact that Britax used to recommend AT OR ABOVE when rear-facing waaaaay back when (10 years ago?) and I really do/did trust them on this. I also think that there's less damage to be done with 1cm of upward movement in a crash versus problems with those seats that tend to have the straps slip down the shoulders when children are almost at the next set of slots (potential ejection or uneven distribution of forces)... There's also the fact that kids always seem to "settle in", and it's easier to account for changes in clothing if you err on the side of high.

FF--My rationale here is that most modern-day seats have numerous sets of close-together harness slots, and if you're an extra 1" high on most seats, but the harness is TIGHT...no biggie. Is 2" below the current harness slots and 1/2" below the closest harness slots (1.5" between the two) REALLY any different than being 2" below and 1/2" above (2.5" between the two) in a larger seat such as the Regent? When my oldest was young, seats had fewer sets of harness slots and quite often you WOULD have the harness coming out at the child's EARS (happens in the Regent still, too)... If the harness is tight, this really isn't a concern for me and the seat should perform the same and crash forces should be distributed the same.

So..really, I think this is splitting hairs because...eh, if the child is properly restrained then 1cm of play here, there or anywhere probably isn't really a big deal.. 1cm below when FF could be accounted for in a little bit of padding in the cover and the seat, 1cm above when RF could be accounted for by a child who "settled in" a bit over the ride... I think we really do have a good cm of play either way--just avoid doing something that's clearly UNsafe and don't worry about a speck of distance here and there.

This sort of reminds me of the debate over whether or not you turn them FF AT the weight or at .1lbs before the weight... That smidge isn't going to really make a difference in the grand scheme of things.

-Nicole.

[snowbird25ca]

Man, kind of a hard question and I really tend to agree with Nicole, though I know one of your seats is a Radian and there can be a big space as it is when moving from one slot to the next at the very top ones...

I'm not sure that there is a super scientific way because in most cases it's just kind of a judgment of how the kid fits in the seat. If the straps seem to wrap around the shoulders at all ff'ing, then move them up. If the straps are slipping off the shoulders rf'ing, or if it seems like the child is getting squished down in to the seat even without the harness being quite tight enough; and the next set up are within 1/8" or so above the shoulders, then I'd move them up.

I guess to try and simplify, rf'ing I tend to look perpendicular to the seat shell. Ff'ing it depends on how upright the seat sits naturally... but I tend to look more at how the straps relate to the child vs. how the straps are coming out in relation to the ground.

But if in doubt, move them up tends to be pretty reliable. :thumbsup:

[hipmaman]

I agree with Trudy and Nicole. It's judgement of how the harness straps fit on the child's body/shoulders as well as the harness level 'rules'.

My rationale are as follows...

RF: The straps have to hug and hold the child in the seat and because the seat is reclined, I would have the 'perpendicular to seatback' line, as most instructions above.

If the 'parallel to ground' line is taken as an indicator for rf, it would not really work since the area in between the 'parallel to ground' would always always be higher than the shoulder and the harness would not hug the shoulder. Only when you get to the 'perpendicular to seatback' line then you have at same level than the shoulder and below the perpendicular line then you have hugging of the shoulder.

Just take the ff/reclined Britax diagram to see what I mean. Imagine this is for rf, the red area would be the area to aim for should this is used for rf, but as you can see it's not hugging the shoulder. There would still be significant room for the child to move up.

FF: Because the seat is (more) upright, guaging by 'perpendicular to seatback' or 'parallel to ground' can pretty much be the same in most cases. You would hit the area where the harness would be at or above the shoulder.

Fitment of harness on the body is important ff. I usually just look straight and level at the child's shoulder and if the slots are not curved below the shoulders and straps are positioned properly/squarely on the shoulders, then it's good for me. This is really guaging by 'parellel to ground' if one is to do it one the side instead of head on/straight at the child's shoulder.

[shauburg]

Thanks for the feedback so far. Mostly matches what I was thinking before I posted:

RF - Use "line" perpendicular (90° angle) to the seat back. This errs on the side of caution and ensures that either way the straps are at or below the shoulders. Also agree if a child seems too crunched and/or straps look about to slide off shoulders, that it's better to move up if next slot is close (using perpendicular line to judge slot closeness).

FF - Use "line" parallel to ground (like in Britax picture). This errs on the side of caution again and ensures that either way the straps are at or above the shoulders.

I must admit though that before I saw the Britax pic in another post a while ago, I would have used a line perpendicular to the seat back for FF too. Not that it would make much difference for most FF installs, as they are more upright than RF installs. But I really do see Britax's point on more reclined FF installs.

When I flip my True Fit FF (which will be soon :(), I think I will definitely have to use the top slot because it's a more reclined FF seat. (Although I didn't actually start this post because of DS & his seats - I was second guessing what I told a friend)

[CDNTech]

Little late to the game (sorry, been on holidays :o), but I agree with everyone else... not really much to elaborate on there. ;)

There's *no way* I'd follow the True Fit's guide for FFing. That seat is fairly reclined FFing (in most vehicles, not all) and that strap would be well below the child's shoulder following that picture... I could see that easily causing spinal compression. :(

[rodentranger]

So if my 5 week old is less than 1/2 inch below the bottom slots on my MA, can I use it for him? My SR is rear adjust and I hate it. He hates the TF.

[Kat_Momof3]

according to current instructions... no


as for the rules... I think britax has that rule about ff with recline (and keep in mind you can't install it ff with recline unless the kid is under 33lbs... so really should be rearfacing) because the recline makes the child fit the seat differently... often times the slots that would appear to high reclined... would be the ones that, if the seat weren't reclined, would be the ones we would naturally use.

I think the worry is that, should the crash move the child and the seat in a way that something malfunctioned and the seat were forced upright, the straps would then be below the shoulders... causing spinal compression.

Heck, maybe it just showed spinal compression in testing when the straps were like that with the seat ff with recline.