Originally Posted by
tardyturtle
I can't say for sure as I've never had the masks deployed, but I have sat on both sides of mainline flights with a lap child. My understanding is that only the regional jets are where the issue is of not having extra oxygen masks.
If I recall correctly, it isn't just one side of another. Another model may have odd rows and even row differences. Or certain logistical issues (remember there is an oxygen generator attached to the mask) near physical barriers.