Safety of Child Seats
I have just watched an interesting lecture by Steven Levitt about car safety for children in the 2-6 age range [1]. The evidence he presents shows that the benefits for children in that age range are at best insignificant and that in some corner cases (EG rear impacts) the child seat may give a worse result than an adult seat belt!
He advocates a 5-point harness [2] for children in the 2-6 age range that is based on a standard adult seat and seems to be advocating a child “booster seat” integrated into the adult seat (which approximates the booster seats offered by some recent cars such as the VW Passat). He has a picture of a child in a child-sized 5-point harness to illustrate his point. But one thing that should be considered is the benefit of a 5 point harness for adults. Race car drivers use 5 point harnesses, I wonder how the probability of a race car dying during the course of their employment compares with the probability of an average adult dying while doing regular driving. I also wonder how a 5 point harness compares to a three point harness with a pre-tensioner, it seems quite possible that a 5 point harness would be cheaper and safer than the 3 point harness with pre-tensioner that is found in all the most expensive cars manufactured in the last few years.
He believes (based on tests with crash-test dummies) that part of the problem is that the child seat will move in an accident (it’s attached to a soft seat). It seems that one potential solution to this is to have child seats that firmly attach to some solid part of a vehicle. I had previously suggested that child seats which replace existing seats as an option from the manufacturer would be a good idea [3].
But there is a good option for making better child seats for existing vehicles. It is becoming common in the “people mover” market segment to design vehicles with removable seats. For example the Kia Carnival has three seats in the middle row which are removable and which attach to four steel bars in the floor. It should not be difficult to design a child seat which attaches to those bars and could therefore be plugged in to a Carnival in a matter of minutes. The Carnival is designed to have the mid row seats installed or removed easily and safely by someone who is untrained, while for comparison it is recommended that a regular child seat should only be installed by a trained professional (IE your regular mechanic can’t do it).
I think we should design a new way of attaching child seats…then we can standardize it via ISO and give it a cool name like ISOFIX
June 26th, 2008 at 8:34 amI want a CRX/Insight-like car with two adult seats in front and two rear-facing child-only seats in back.
5-point belts sounds great, but where do I go to change into my kilt, toga, or skirt?
June 26th, 2008 at 8:51 amMany cars in Australia are sold now with ISOFIX points (where the child seats attach via these to the car chassis), but for some reason, you still can’t buy ISOFIX safety seats here. The same manufacturers already make them for overseas markets: something seems to be wrong with our standards process.
June 26th, 2008 at 2:16 pmMe: ISOFIX only has two attachment points and allows the seat to move.
Don: Rear facing seats in general offer advantages. Some child car seats advise that they are not to be fitted in rear facing seats, I guess it’s because of the rear-end collision issue that Steven refers to. But I guess child seats according to Steven’s design which face backwards (or 2+ yo children in regular rear-facing adult seats) would work well.
Good point about a kilt or skirt. But I guess you could have a four-point seat belt that attaches around the waist and over both shoulders, that should be better than a three-point belt but also allow a wider variety of clothing to be worn.
James: Yes. The entire car safety process is grossly flawed, the total lack of proper child and female crash-test dummies is the most obvious example.
June 26th, 2008 at 4:22 pmBetter than a booster seat is a good driver. If you don’t get into wrecks, you don’t need restraints. Not that I advocate people letting children roam around unsecured in a vehicle, just that it doesn’t make sense to be overprotective of children in this day and age. If they don’t make it to adulthood, so fucking what? It’s not like there isn’t 8 billion other people already on this planet.
June 27th, 2008 at 12:52 pmbaloo: Avoiding crashes is a good idea, unfortunately there is no shortage of idiots on the roads, and the road quality and signs are sometimes lacking so even if you are a perfect driver you will still have a risk of collision.
June 27th, 2008 at 1:53 pm