RE: Why do Euro infant car seats only have 3 pt harnesses?
I'll throw these out here more as ideas than facts since my memory is murky about what I read and the reliability of the source.
1. I think there are differences in the seatbelts that might be used ot attach a car seat, and accounting for that variation is one reason car seat standards differ in countries. In the US, I think lap belts in back seats were allowed much long than in Europe , so car seat regulations in the US have to account for the range of cars on the roads. THat might relate to requiring a base.
2. Not sure if there is a significant difference in safety between an infant rearfacing seat with 3 vs. 5 point harness. I think a CPS tech on these boards implied there wasn't much difference.
3. I think car seats in Europe cannot have a chest clip because there can be only one release point for car seats (for a faster release? Seems unlikely that in a life-threatening situation, there would be enough time for speed of release to be a factor.)
4. Americans expect high convenience in all their products, and the snap in and out mentality of using a base suits us perfectly. Europeans just may not demand this convenience as much.
5. I read car seat brochures in Belgium that say babies can be put in the FRONT seat, rearfacing, as long as there are no airbags, and I saw people do it there. I don't think you'd ever read anything in the US that suggested doing this.
6. I do believe that a car seat directly installed with a seat belt is more secure than one installed in a base, where it's the base rather than the seat that is actually belted in. So maybe bases are considered inferior in Europe even if they are convenient.
I just gave away my Euro car seat today to someone here in the US who really wanted it despite the lack of a base, so I was just talking about this this morning. I put it on freecycle and someone else wanted it just as a backup seat and really wish I had ignored first come, first served and given it to him.
Advice and commentary on living overseas
DD1 15, DD2 12, and DS 9