Comment by aquaphile | Hacker News Reader

Comment by aquaphile | Hacker News Reader

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1. Safety (* see below)

2. Ease of Installation (* see below)

3. Bauhaus Design

4. 1-Hand Operation

5. Ease of Cleaning

6. Built in Rocker (a full one)

7. Quiet (* see below)

* Safety > The US regs are pass/fail so lots of seats on the market have mediocre test scores that don't reflect the real danger of severe concussions. For those of you interested in digging into the obscure world of Head Injury Criterion: greater than 390 HIC is linked with severe concussions (Source: Proposed limits for HIC From Kleinberger et al., 1998, and Eppinger et al., 2000.) Kioma seats do a number of things (crumple zones, etc) to create a lower (better) HIC score. By comparison some of the top sellers in the industry are at 600+ HIC.

* Installation > The regs don't have standards that really address this, but the incredible complexity of legacy car seats has led to a lot of installation errors by parents and caregivers. This can lead to some really unpleasant outcomes and injuries. We designed KIOMA to minimize use and installation errors by making things as simple and intuitive as possible. This seat is optimized for lap belt use only (no base required). The companion base has a number of innovations too that make it intuitive and easier to use.

* Quiet > There are no clicking or snapping or button parts that wake a sleeping child (with the exception of the harness buckle). This is the quietest baby car seat made.

Regarding safety, do you have any links around the test results for the Kioma, or other car seats? You've mentioned a lot about the safety scores/test results in comparison to other car seats, but I couldn't seem to find a single mention of that stuff on the website? I also tried to see if something like Consumer Reports had a review of a Kioma car seat (either the current one or the carbon fiber one) but they had nothing.

Test Results > NHSTA used to publish their test results of all car seats, but no longer do so. FMVSS 213 (the US standard) tests for Head Injury Criterion (36 millisecond), Excursion, and Peak Acceleration in a frontal car crash. So keep in mind the utility of the results has limits, and doesn't test for a whole lot of things that are part of real-world usage in and out of a car. *Big grain of salt.*

I'll give you some real numbers and leave the comparison for you to do (lawyers get itchy if we do the comparing directly). Our carbon fiber seat's best result is HIC 197 in FMVSS 213 testing with a Crabi 12-mo old test dummy. Our friend Eli at Magic Bean's reviewed it in a video at https://www.youtube.com/watch?v=fGaU9R6jHCQ The current car seat for sale is of a similar class but doesn't have the $2500+ price tag of a carbon fiber seat.

If you're still curious, we can take this off HN: drop me a line at support@kioma.us and just mention HN and your HN profile name.

Why only lap belt? Isofix is so easy.

You get both: isofix/latch as well as lap-belt. Each car seat is sold with an accompanying Latch (aka Isofix) base so you can roll with whatever you prefer. However, lap belts are ubiquitous and work really well.

Reasons to use a base:

1) Convenience. It is nice and fast to click-in, click out with a car seat. Super fast and easy.

2) Protect the seat cushions of the car.

3) More constraints on pitch rotation. Which can be good or bad depending on how the seat is designed and rotation is used.

Reasons to use a lap belt only (no base):

1) It is intuitive. Everyone -- including grandma, grandpa, and the babysitter -- knows how to use a lap belt (as opposed to a latch/isofix base).

2) It is ubiquitous. Every automobile and plane seat has one. So if you're hopping into an Uber, no problem.

3) Lab belts are designed to stretch which is actually really good in a collision. The stretching lowers peak acceleration, and therefore lowers the likelihood of injury.

4) Total system weighs less, which translates into less force in a collision (F=ma).

Many thanks for the thoughtful reply! Coming from Europe here where it’s been on every car for about 20 years so has become very much the norm.

Belt (1) troubles me slightly in that it’s easy but not necessarily intuitive enough for grandma to get it right every time (and indeed many don’t). The base has the great benefit of being definitively installed correctly (all goes green / stops beeping).

The reported numbers on belt errors are pretty terrible: https://www.besafe.com/child-car-seat-misuse-study/

A good dialogue is always fun. Thanks for bringing some science to the thread.

You've hit the nail on the proverbial head regarding misuse. Misuse is a problem across installation types: belt-only, and with Latch/Isofix. Some people get so confused they install with both methods.

Lowering misuse is a top design goal. Stated differently: we want to make things so simple that people have to work hard to make a mistake.

You are absolutely correct that belt misuse is a problem (per the cited GDV study). Latch misuse is still a problem too, though.

The studies make clear that misuse is common across installation types, to various degrees. The studies don't do a great job of exploring why the misuse occurred (The 2005 NHTSA study below did ask some good follow up questions). For example, Why did someone not use the belt path correctly? Was it because the slot was too narrow? Was it not visually obvious? Why did someone install both the Latch/Isofix anchors onto the same mount point? Why did someone leave too much slack in the Latch/Isofix anchor or the seat belt? Etcetera. The reasons why people misuse a seat are very valuable to improved public education and improved product design.

NHTSA's 2005 large field study found 39% of CRS (aka baby car seats) were incorrectly installed with Latch. Many of those had multiple errors (e.g. twisted belt plus latch connector turned upside down). Table 11 has the details in https://www.nhtsa.gov/sites/nhtsa.gov/files/latch_report_12-...

10 years later, NHTSA's 2015 study with NCRUSS data found misuse was still persistent: "Overall misuse is considered as having at least one defined misuse present in the car seat or booster seat – the seat may have one or multiple misuses, where one misuse has the same contribution as multiple misuses. The overall misuse is estimated to be 46 percent with a 95 percent confidence interval ranging from 39 percent to 52 percent. By car seat or booster seat type, estimated misuse rates were 61 percent for forward-facing car seats, 49 percent for rearfacing infant car seats, 44 percent for rear-facing convertible car seats, 24 percent for backless booster seats, and 16 percent for highback booster seats." Source: https://crashstats.nhtsa.dot.gov/Api/Public/ViewPublication/...

So for all those parents out there, read your seat's user manual. The user manual will make it clear how to properly and effectively use the seat belt or the Latch/Isofix anchorages.

Isofix is easy in theory but if you don't know exactly where the fixing points are, then it's like fumbling around in the dark. Sometimes it's hard to see the fixing points while trying to get the seat on.

I think that situation is something many parents recognize. Usually when the baby is screaming etc.. wonderful.

Once you've click the base in, it's easy next time though. Yet, my wife still considers fitting the seat as the man's responsibility. :-)

Parent here too, with three different seats (two are rotating, permanently affixed to the base, 0-3yrs, one is a removable base, 0-~1). All of which seem to have little torches on the isofix lugs, and the little one feeling infinitely more stable when using the isofix and leg as opposed to just the base. I will say the permanently affixed ones / bases weigh a tonne. Being able to click in and out was a delight when we were able to use the little seat.

I'm not sure if its a brand thing, but the isofix bolts on my last cars (Volvo, BMW, Audi) were all really well signposted, and in little plastic housings which you couldn't miss, even fumbling around. The ones on my wife's Ford are just sort of hiding behind the cushions, which doesn't seem as elegant.

Toyota Land Cruiser here. They are sort of visible if you have proper lighting or if it's during the day. They hide behind leather flaps so best bet is to feel your way to them.

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