Is it “safer” to teach CPSTs to counsel parents to disconnect a tether at 40 pounds for a child in a high-weight-harness CR when the vehicle manufacturer does not specify a tether anchor weight limit, or to teach that a tether should be used as long as possible following the CR manufacturer’s instructions?
That is the key question that we, Safe Ride News and SafetyBeltSafe U.S.A., have asked the National CPS Board (NCPSB) curriculum-writing team in our joint comments regarding updates to the curriculum. Without any data to the contrary, it seems to us very risky to tell CPSTs to counsel CR users to disconnect a tether for a heavier or taller child in a harness CR when the CR manufacturer’s own limits are much higher.
The brief curriculum content about anchor weight limits for tethers remains for us as CPS advocates, technicians, and instructors one of the most complicated and frustrating parts of the training course. Regarding that topic (which we emphasize is specific to tether anchors, not lower anchors), we sent an open letter to the NCPSB that was reprinted as an editorial in the May/June issue of Safe Ride News and is available on the SRN website. We suggest that anyone interested in this topic take a look and voice their thoughts to me at [email protected].
We do want to recognize and appreciate the Herculean task that the curriculum update team has taken on. The team is composed of the entire NCPSB (www.cpsboard.org).
Deborah Davis Stewart
Publisher, Safe Ride News
Editor’s note: CarseatBlog strongly recommends use of top tethers, except where clearly prohibited in writing by a weight limit or other restriction in the child restraint or vehicle owner’s manual. The lack of consensus among manufacturers, regulators, agencies and advocates about tether limits simply confuses parents. Ultimately, this confusion can result in failure to use top tethers, especially for older kids who would benefit the most from their use. Lacking significant published evidence, applicable standards or relevant policy statements from agencies like the AAP and NHTSA, we must have clearly stated limits in the owner’s manuals and warnings on labels if there is a real risk in using a top tether. This allows technicians to limit their liability and most importantly, for parents to keep children as safe as possible in their vehicles. And that, of course, is our goal.
After reading the recent blog entry about “making a mom cry,” I decided to reply here, because I think it’s actually more relevant to this discussion.
What this all comes down to, whether we’re discussing tether anchors or expired carseats or misuse, is that the system we have in place right now is too complicated. While carseats are effective at preventing deaths and injuries, the amount of energy and education required to correctly use a carseat is excessive. For adults, we have a system in place that is easy; I sometimes point this out to parents who are dismayed to learn the mistakes they’ve made by showing them my SafeKids checklist form and letting them see that I have ONE bubble to check for whether or not the parent was safely restrained – compared to the thirty or so bubbles for the child.
So, we have adults who have had it drilled into their heads to “buckle up” in order to keep themselves safe, but for kids (who are supposedly even more precious to us than an adult) it becomes an insanely long list of steps to keep them safe. If adults had to go through a similar list, no doubt we would see the same high rate of misuse that we see with carseats. Imagine telling an adult “You can’t just buckle your seat belt, you have to lock it,” “You can’t just buckle and lock the seat belt, you have to adjust it to your height and then make sure it’s snug,” “You can’t just buckle the seat belt and lock it and make sure it’s snug, you have to attach this third strap,” or “I’m sorry, you bought the wrong seat belt for your age group.” How many adults do you know who would go through that amount of effort for themselves? Would YOU? It’s really no wonder they’re confused and not able to use carseats correctly.
Bringing this back around to the topic of the tether anchors, my point is that the real problem here is that of further complicating an already too-complicated system. Rates of use for top-tether anchors are already abysmal, mostly due to the additional step required in a system that is already too confusing and too complicated. Weight limits on top tethers seems completely beside the point when you consider that half of the carseats aren’t tethered in the first place. The point isn’t whether or not it’s safer to use a top tether above a certain weight, and it’s not whether there should even be weight limits on the LATCH system – the point is, we should be simplifying child passenger safety, not complicating it.
I basically say what I said in my comment plus what KQ says about how there’s no documentation of tether failure. If it does fail, it would be after the initial crash forces have already been absorbed. Like KQ, I’ve yet to have a parent remove the tether. Otoh, for techs who aren’t as diligent about explaining that to parents, I believe it’s really dangerous. That 4-6″ of head excursion could be the difference between a serious head injury and none. Since we know head injuries have far-reaching implications past the initial recovery period, we should be doing all we can to eliminate it. Not tethering because there’s a possibility the tether may fail after initial crash forces is irresponsible.
OK, now I’m curious – what DO you other CPSTs tell parents when the top tether anchor limit comes up? (I mainly work in low-income urban areas where we distribute new seats, which are nearly always 40-lb. limit seats, so this doesn’t come up often for me.)
I think it’s ridiculous that we’re supposed to tell them about limits that aren’t even in the manual. Sure I’m all for that with lower anchors- to be cautious. But once I’ve explained the risk/benefit ratio as we know it- I’ve never ever had a parent choose NOT to use the tether. And why should they? There is no indication that tethers fail in real life and if they were to, no indication that that would be more harmful than not tethering! Period! Add in the risk of a completely unsecured tether anchor in a seat that is NOT tethered (most parents leave the LATCH and tether straps just lying around if they don’t use them) and I think this whole business is ridiculous (did I already say that?)
The curriculum says, “You should remind parents to use top tethers whenever possible.” Why should it be incumbent upon the technician to determine the top tether weight limit of a vehicle when it’s not specified by the vehicle owner’s manual? It says one of two things to me: either the vehicle manufacturer doesn’t care about a top weight limit for the tether and therefore it’s unimportant or the vehicle manufacturer has determined the public is savvy enough to call and inquire. Since we have a static tether use rate, it’s clear the public isn’t savvy enough to question using tethers, let alone contact the vehicle manufacturer. Either way the vehicle manufacturer should be the one holding the liability about top tether weight limits, not technicians who are now the ones on the firing line, explaining to parents that no, “no failure has been documented to date, yet I have to advise you to remove the tether” just when your child is large enough to really need it. It removes all credibility I have as a technician when I have to tell a parent that and if the parent decided to remove the tether based on what I’ve said, I *know* they’re leaving with their child less safe.
We have years and years of experience with tethers now and it seems that if tether failure was indeed a problem, we’d have heard of it by now. Our first higher weight harness seats were available in retail stores over 10 years ago. That ten + years, plus Canada’s years of experience with harnesses that go beyond 40 lbs., surely must be enough time to gather *evidence*. That lack of evidence suggests to me that lawyers are driving the decision behind telling techs to just stop at 40 lbs. and since when are lawyers qualified to make technical decisions such as this?
I’m not even going to speculate as to whether there are or should be limits to top tethers. If the National CPS Board wants CPSTs to tell parents that it’s safer to use a top tether but to discontinue use at a certain weight, please tell us what to tell the parents. Give us a script, even!
When a parent asks why they should stop using the top tether, and I don’t know the reason (much less have a good understanding of the reason), I lose credibility when I don’t have a ready answer. And “because they said so” doesn’t usually go over very well, especially when there’s no top tether limit listed in the car seat manual or the vehicle manual.
Please, if there’s evidence that it’s better to stop using the top tether at a certain weight, tell us. And tell us what to say to parents.
Okay, after letting this bounce around my subconscious for the day, here’s what I’ve come up with:
1. The same people who wrote the anchor strength standard should tell us what that means in terms of child weight. Presumably they have some idea and didn’t just pick a random number of Newtons, it was based on something. If a vehicle meets the minimum strength standard, then its anchors are strong enough for a child plus seat weight of X.
2. NHTSA needs to require weight limits in the vehicle owner’s manuals. I’m talking about limits for both the lower anchors, and the tether anchors. The limit may be expressed in terms of combined child and seat weight, or just child weight. The minimum stated weight limit should be no less than X from number 1 above.
3. Child restraint manufacturers should also either include a clearly stated weight limit for lower anchors and tethers, or the statement that the lower attachment and/or tether may be used to the limits of the seat, as long as the vehicle’s limit is not exceeded, and specifically direct the caregiver to look up the limit in their vehicle’s owner manual. If the child restraint weight limit is less that X from number 1, then they can omit the parts about not exceeding the vehicle limit and having to check the limit in the vehicle owner’s manual. Many well-intentioned caregivers read the manual that comes with the seat but don’t think to read the vehicle manual as well.
@Pixels- That’s the thing. If the NHTSA (or other agency) does have actual data/studies showing increased risks with failed tether anchors vs. no tether anchor, all we need is a clear policy statement that there is a real danger to children and a corresponding requirement that manufacturers list any relevant limits in the owner’s manual. There should also be a warning label, presumably on or near the tether anchor, as we have with airbag dangers.
There is clearly a limit for top tether anchors and we do need a procedure like you suggest. In the case of harness systems on child restraints, at least the manfuacturers clearly state the limit in the manual and on the labels. The issue with top tether anchors is conveying such limits to the public and alerting them to any danger. That is how we protect children from harm and protect technicians from liability. Having technicians instruct parents to discontinue the use of a safety feature at an arbitrary limit with no clearly published evidence or statement from manufacturers or the NHTSA is very scary to me. Scary enough to where I might elect not to assist a parent with a high weight harness restraint system. Am I really supposed to tell a parent that an important safety feature suddenly becomes a dangerous risk at 40 pounds, even though I can’t point them to a written limit in the manual or on a label or even a prominent warning on the NHTSA website? I certainly don’t want a child injured because of undocumented limits and if that was ever to happen, all the liability is on me because there is nothing in the manual to support my advice!
“A 35lb child who is in a forward-facing restraint that is top tethered during a high speed collision could put more force on that top tether anchor than a 60lb child in a low speed collision.” … “Given the variables of different collisions, I would submit that it is impossible to accurately list a top weight limit on a top tether anchor.” The same arguments could be made about the harness weight limit. In a high speed collision, it’s possible that a child at or near the limits of the harness weight limit will exceed the child restraint’s capability to protect the child. In a low speed collision, a 55 pound child in a 40 pound harness may still be adequately protected. [Note, I am NOT suggesting that a 55 pound child is safe in a 40 pound harness. If your child is over the weight limit they need a new seat.] A certain crash scenario is selected and used in crash testing, and it is deemed that that scenario is sufficient to determine what child restraints are safe and which aren’t. Why shouldn’t a similar procedure be used to determine weight limits for tether anchors? Pick a crash scenario, preferably the same one that is used to test child restraints, and figure out the weight of child that the tether anchor is strong enough to support in that crash scenario.
“Given that the top tether will have done at least part of it’s job already even if it did fail” was the argument used by Britax to try to avoid a recall when its tethers were failing. NHTSA refuted that, saying that the test results with a used-but-failed tether were the same as an unused tether: increased head excursion in exchange for reduced head and chest forces. http://www.gpo.gov/fdsys/pkg/FR-2007-08-21/html/E7-16408.htm for more info on that.
What I find frustrating about the top tether weight limit discussion is that top tethers are not tested at a specific weight – it is a simple pull test at a specific minimum # of Newtons. Some manufacturers may very well test beyond the minimum number of newtons required, but all of them have to test to at least the minimum.
How does this translate to real world use? A 35lb child who is in a forward-facing restraint that is top tethered during a high speed collision could put more force on that top tether anchor than a 60lb child in a low speed collision.
Given the lack of real world failures in properly installed top tether anchors, I would hope that the curriculum review would reflect what Canada has known for years. There is huge potential liability to advising parents to disconnect a top tether at a weight limit that is in many aspects arbitrary due to the unknown variables of any collision. Given that the top tether will have done at least part of it’s job already even if it did fail, it makes me wonder how much of the concern about top tether weights is theoretical legal concern “just-in-case” the top tether failed. Perhaps those concerns should focus on the inherent risk of a seat that isn’t top tethered and the increased risk of impacting the vehicle interior.
I also feel concerned that there is enough communication of American information to Canadians that it could lead to premature graduation to booster seats in the cases of young heavy children. Given that the vehicles are for the most part identical between markets, I think it is a reasonable question to wonder why it wouldn’t be ok in the US if there aren’t problems showing up in real life use in Canada.
Given the variables of different collisions, I would submit that it is impossible to accurately list a top weight limit on a top tether anchor. And if an accurate weight can’t be listed, I fail to see how it would be responsible of a technician to recommend removing the tether due to a child’s weight.
I hope that all these factors are things that the review committee is taking in to account during the review process. NHTSA and Transport Canada have close contact on many matters. Perhaps it is worth requesting that NHTSA talk to Transport Canada regarding our national experience with top tethering that spans nearly two decades now.
Thank you for this post.
I am a Canadian technician. I don’t know a single one of my peers who has ever identified an instance of top tether failure as a result of exceeding the weight limit of that anchor. We have had “higher weight harnessed” seats–combinations to 47 and 48lbs–for over 10 years now. Because top tethering has been mandatory since before higher weights were introduced, this is an excellent example of real world testing of top tether anchorage “weight limits”.
As a parent, I would rather risk a potential (but seemingly unlikely) failure during the crash event versus a 100% failure in the absence of the tether. We may be wrong, however. But until there’s some real world data out there identifying the dangers of top tethering over the weight limit, I’ll stick with my real world data supporting the benefits of limited head excursion.
Thank you SRN and SBS USA, for addressing this with the curriculum committee and for keeping attention focused on this important issue. It is critical to our core mission to have a consensus on this issue that is evidence-based. As child passenger safety professionals and educators, we are obligated to provide parents and caregivers with the resources and education they need to make informed choices and decisions for the children in their care. Currently, according to the standardized curriculum, the “Gold Standard” of protection is only an option for certain children, depending on how much they weigh and what vehicle they happen to be riding in that day. That is most definitely not Best Practice and we have an obligation to our children to come up with better recommendations.
Thank you! It’s hard for me to see how no top tether at all could be safer than a top tether beyond the vehicle’s manufacturing limits. This really does need to be clarified. I choose to use a top tether for a child who is over 50 lbs in my vehicle that doesn’t specify, but I do not feel comfortable either recommending this to someone who comes to a seat check nor do I feel comfortable recommending that they disconnect the tether entirely. We need a definitive answer, and if it’s actually safer to use no top tether at all than to exceed the car manufacturer’s recommendations, we need a clear understanding of WHY.
Thank you for addressing this issue. I expressed my dissatisfaction with SafeKids’ stance on the CPSP yahoo group, but I’m afraid as a “lowly tech” my opinion doesn’t matter much. Hopefully they’ll listen to SafetyBeltSafe and Safe Ride News, though.