Rear Facing: Technical Details

Rear-facing: why do it and how to make it work is one of our most-read articles, and full of lots of fabulous information and resources. It is rather long, however, so we’ve decided to save some of the extra stuff for this piece!  All the extra stuff you didn’t know you wanted to know about rear-facing, questions that often come up, and more detailed technical information for those of you keen on the why of it all!  Hmmm, if you ARE keen on knowing why and how and everything else maybe you should become a car seat technician…

In the meantime, read on!  Many thanks to those who provided pictures for this article.

 

What’s the point of a rear-facing seat if you’re rear-ended?crst6

Strictly from a physics perspective a passenger IS safer forward-facing while being rear-ended — everything moves toward the point of impact (the back) and then rebounds forward (the opposite of what happens in a frontal crash).  A rear-facing child has nothing supporting the head as it moves toward the back of the vehicle.

In reality if someone rear-ends you, then THEY are having a frontal crash.  Frequently they then plow you into whatever’s in front of you causing a frontal crash for YOU.  Fatal rear end collisions are statistically far less frequent and at much lower speeds than frontal collisions.

Since we can’t predict what type of crash we will have in advance, we need to play the odds both for frequency and severity.  Frontal, frontal-offset, and side impacts are combined the most frequent and most deadly, and rear-facing provides vastly superior protection in all of those types of crashes.

Do you need to see some pictures? Here’s an amazing rear ender crash with a happy ending.

 

Loading rear-facing kids into the third row

DSC00377

What if the only way to rear face your child(ren) is if they’re in the third row? Many three-row vehicles have one tether anchor there (required for forward facing), and sometimes none at all. It’s up to the manufacturer of the vehicle where those anchors are installed so long as there are three total. Often the placement is inconvenient and parents are faced with putting rear-facing children in the 3rd row to leave the 2nd row available for forward facers.  But…how do you get them IN there? And how do you buckle?  If kids are old enough they can scamper in themselves by climbing on adjacent seats. If they’re smaller they can also be loaded and buckled through the back hatch.

 

Happily rear facing

 

 

 

These three kids (ages 4, 11 months, and 2.5) are rear-facing in a Chevy Avalanche.  The middle child is loaded first over the low sides of the car seats, and the older two can climb in themselves. Easy peasy!

 

 

 

 

 

 

What’s the point of rear-facing tethering? Does my seat allow it? How do I do it?

This fabulous summary was written by Children’s Restraint Systems Technician-Instructor Natalie Day.

Aussie style rear-facing tethering

Aussie style rear-facing tethering in a Britax infant/child seat.

Rear-facing tether is almost never required (the exception being Britax G4 seats manufactured between Dec 2013 and June 2014) , and may or may not benefit the child depending on the specifics of the collision.

There are two types of rear-facing tethering: Australian (over the top to the designated forward-facing tether anchor) and Swedish (to the front vehicle seat track, using a D-ring strap provided by the child seat manufacturer). Australian tethering is to reduce downward rotation during the collision event, while Swedish tethering is designed to minimize rebound after the initial collision and to minimize side movement in a side impact crash. However, neither of these are exactly the same as on Aussie and Swedish child restraints.  Aussie seats also have an anti-rebound bar, while the attachment points and installation on Swedish models are quite different.

 

RFTether

Swedish style rear facing tethering to the seat track of the driver’s seat.

In Canada, rear-facing tethering is only allowed on Sunshine Kids/Diono and Britax infant/child seats.  Britax allows both Aussie and Swedish style, and Sunshine Kids/Diono allows only Swedish style.  Risks of rear-facing tethering in the Swedish style include increased neck loads for young infants, and the potential issue of creating your own anchor point in the vehicle without the vehicle manufacturer’s permission/approval.  Before doing so you MUST determine if your vehicle manufacturer permits the creation of an anchor point with the child restraint-supplied D-ring; as of this writing there are no known vehicle manufacturers that expressly permit Swedish-style tethering.

Britax Boulevard rear facing tethered to the designated forward facing anchor point in the row ahead.

Britax Boulevard rear facing tethered to the designated forward facing anchor point in the row ahead.

If your vehicle is new enough to have advanced airbags, the tether strap pulling up on the seat track may affect the air bag sensors, decreasing protection for the front passenger if the air bag doesn’t deploy properly.

Benefits of rear-facing tethering Swedish style include increased lateral stability in a side impact collision, and a reduction of rebound after the initial collision, both of which may have a protective effect on the seat’s occupant. For an older, heavier child, this would be more important.

Rear-facing tethering Aussie style has less risk because you use a designated anchor point, however it is harder to get the child in and out of the restraint with the tether strap.

 

Whether rear-facing tethering is appropriate (or required) for your child and your vehicle should be evaluated on a case-by-case basis.

 

Anti-Rebound Bars

Anti-Rebound Bar on a Clek Foonfimage-3

New crash test standards that came into effect in Canada on January 1st, 2012 included a new component commonly called the ‘Anti-Rebound Standard.’  In essence it limits how far a child’s head can travel back toward the rear of the vehicle after the initial frontal impact.

All seats currently for sale pass this standard in some way, mostly due to either the shape of the seat itself, or the handle in the up position (a sort of ‘roll bar’ if you will) on infant seats.  A few seats have more obvious structural components to limit rebound, and they are called anti-rebound bars.  They are used only in the rear-facing orientation, and are available at the time of writing on the Clek Foonf, Clek Fllo, First Years True Fit, Peg Perego Convertible, Britax Chaperone, Maxi Cosi Prezi, Britax G4 seats produced after June 2014 (and available as a retrofit on seats manufactured prior to that date – call Britax), and Britax ClickTight Convertibles.

 

Side Impact Protection and Rear Facing – What’s the Connection?DSC00150

Transport Canada does not have standards for side impact protection. Many manufacturers claim side impact protection of one type or another — EPS foam, EPP foam, head wings, air bags — and our feeling is that it likely is beneficial to some degree.  A deeper shell or head wings also likely provide some protection from intrusion injuries as a physical barrier between foreign objects and the child’s head.  Manufacturers generally do not release their side-impact crash tests though, so there is no way to compare between seats, or to know if testing would be typical of a real crash.  Because there is no standard we’re comparing apples to oranges when looking at the different options between manufacturers.

Rear facing itself offers tremendous side impact protection.  It is a very rare (almost never) crash where you are not moving at all and someone hits you directly side-on. Most side-impact crashes have some forward movement, causing the head of a forward-facing child to move out past the shell of the seat. The statistic that rear-facing is 532% safer comes largely from side impact crashes. They are the most deadly type of crash as there is less protection in the vehicle’s structure from the side versus the front.  A rear-facing child in a side-impact crash (with some degree of forward motion) is pressed into and contained by the shell of the seat at the same time that the head, neck, and spine are cushioned and supported by the shell of the seat.  Rear-facing in ANY seat is safer than forward facing in the most embellished of seats with potential side-impact protection.

 

That’s all folks.  Unless we missed something.  Is there an element of rear facing that you’d like us to expand upon?

So what’s the take home message?  Rear face as long as you can. Really – the longer the better, to the limits of the seat. Aim for age two at a minimum and then go from there.  Plenty of seats are available that will do that for even the tallest of kids.  More money doesn’t mean safer, but it might mean some convenience features that make it easier for you to rear face as long as possible, so shop carefully for a seat that fits your child, your budget, your car, and that you can use properly every single time. THAT’S the best one for you!

We appreciate feedback – please leave a comment below.

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