Atkinson is an English-language surname. The name is derived from a patronymic form of the Middle English Atkin.
These are much more conservative than state laws, in general (for instance, everyone should be in a booster seat from about age 4 to at least age 8) but remain less conservative than some of the european standards (for instance, the European Child Safety Alliance recommends that children remain in rear-facing carseats until 3 years of age).
), as Chloe states, allows children to stop using car seats at 40lbs in the back seat provided there are no shoulder belts. It lists other exemptions as well (e.g. if you have no back seats, or your back seats face sideways, or you already have three kids in the backseat, you're allowed to let your six-year-old ride up front).