October 2007
Car seats update
In our new tests of infant car seats, all performed adequately in simulated head-on crashes at 30 mph, the government standard.
But we found differences in how easy the seats are to use and how securely they fit in a variety of vehicles--measures important
to the safest ride for your baby.
For our latest tests, we re-evaluated 11 of 12 models we tested for a February 2007 report that we retracted because of testing errors. (One model, the Eddie Bauer Comfort, has since been discontinued and is no longer available.)
In the flawed February 2007 report, we attempted to test infant car seats in simulated 35-mph front and 38-mph side crashes. Those are the speeds that vehicles themselves are routinely subjected to in government tests for crashworthiness. The article reported widespread failures of the car seats, but the testing errors resulted in our withdrawal of those Ratings. (For details, see How our car seat tests went wrong.)
All the infant seats we tested are rear-facing carrier models that snap in and out of a base. The base connects to the car by means of the vehicle's safety belts or LATCH attachments. LATCH, which stands for Lower Anchors and Tethers for Children, includes fasteners that connect the base to metal anchors in the car.
How we tested
We conducted the crash tests at an independent contract lab, a different one from the lab we used previously. In the tests, a 22-pound dummy, simulating an average 12-month-old, is secured in the infant seat. The seat is attached to a piston-driven "sled" that mirrors the acceleration vehicle occupants would undergo in a 30-mph head-on collision into a rigid barrier. The government requires that all car seats and boosters on the market withstand a frontal impact at this speed.
We crash-tested each seat at least twice so that we could check performance using vehicle safety belts to secure the base and, separately, using LATCH attachments. Two independent consultants worked with us to review the tests.
In addition, certified child passenger safety technicians assessed how easy each seat was to use and how easily each seat could be installed in a hatchback, minivan, sedan, SUV, and wagon.
What we found
All 11 infant car seats met the government crash standard in belt and LATCH modes, so the Ratings do not differentiate between those modes.
But some seats were easier to use and easier to fit in various vehicles. The differences in overall scores among models are the result of differences in those features.
For example, almost all features of the top-rated Chicco KeyFit were easy to use, including its recline adjustment device, LATCH connectors, and harness adjusters. And we could secure it snugly in the five test vehicles.
By contrast, the Combi Centre ST and the Evenflo Discovery received much lower combined scores for ease of use and fit to vehicle. We found the Combi's handle difficult to move, and the Discovery was harder for us to disengage from its base than the other seats. (See the Ratings.)
The Discovery was also the only seat in our tests that had a three-point harness and lacked an adjuster to change the angle of recline of the base. (A newer model, the Discovery 5, adds a safer five-point harness but also lacks a base adjuster.) That made it more difficult for us to achieve a suitable angle of recline when we installed the seat in our five test vehicles. Babies in infant car seats must recline enough so that their head doesn't tilt forward, possibly obstructing their airway, according to the National Highway Traffic Safety Administration, the government agency that regulates car seats sold in the U.S. But if the seat leans too far back when installed, infants can be injured or ejected in a crash, NHTSA says.
Manuals for some of the seats we tested say that a positioning device may be needed to achieve a suitable angle of recline. The Discovery's manual, for example, notes that in some vehicles it may be necessary to place a tightly rolled towel or small blanket underneath the front edge of the base to provide enough recline for an infant's head to lie back comfortably. Indeed, for our fit-to-vehicle test we had to use a positioning device with the Discovery in all of our test vehicles; no other model required a positioning device. We think a base adjuster that is integral to the car seat generally makes the seat easier to install appropriately.
It is critical that you read, understand, and follow all manufacturer instructions so that you use the car seat correctly and your baby is comfortable and secure. Many details are unique to the specific model you own. For example, parents may know to adjust the harness as their child grows, but some seats also require you to change the position of the crotch strap or the seat may not perform as designed. The key point is that, in contrast to some other consumer goods, infant car seats are not the type of product where you can get by without instructions and wing it on your own.
As this report went to press, the Combi Centre ST, Compass I410, and Safety 1st Designer were to be updated along with the Evenflo Discovery, though the tested models are still available. In our ongoing evaluations of car seats, we will test those and other new models.
No matter which car seat you choose:
For our latest tests, we re-evaluated 11 of 12 models we tested for a February 2007 report that we retracted because of testing errors. (One model, the Eddie Bauer Comfort, has since been discontinued and is no longer available.)
In the flawed February 2007 report, we attempted to test infant car seats in simulated 35-mph front and 38-mph side crashes. Those are the speeds that vehicles themselves are routinely subjected to in government tests for crashworthiness. The article reported widespread failures of the car seats, but the testing errors resulted in our withdrawal of those Ratings. (For details, see How our car seat tests went wrong.)
All the infant seats we tested are rear-facing carrier models that snap in and out of a base. The base connects to the car by means of the vehicle's safety belts or LATCH attachments. LATCH, which stands for Lower Anchors and Tethers for Children, includes fasteners that connect the base to metal anchors in the car.
How we tested
We conducted the crash tests at an independent contract lab, a different one from the lab we used previously. In the tests, a 22-pound dummy, simulating an average 12-month-old, is secured in the infant seat. The seat is attached to a piston-driven "sled" that mirrors the acceleration vehicle occupants would undergo in a 30-mph head-on collision into a rigid barrier. The government requires that all car seats and boosters on the market withstand a frontal impact at this speed.
We crash-tested each seat at least twice so that we could check performance using vehicle safety belts to secure the base and, separately, using LATCH attachments. Two independent consultants worked with us to review the tests.
In addition, certified child passenger safety technicians assessed how easy each seat was to use and how easily each seat could be installed in a hatchback, minivan, sedan, SUV, and wagon.
What we found
All 11 infant car seats met the government crash standard in belt and LATCH modes, so the Ratings do not differentiate between those modes.
But some seats were easier to use and easier to fit in various vehicles. The differences in overall scores among models are the result of differences in those features.
For example, almost all features of the top-rated Chicco KeyFit were easy to use, including its recline adjustment device, LATCH connectors, and harness adjusters. And we could secure it snugly in the five test vehicles.
By contrast, the Combi Centre ST and the Evenflo Discovery received much lower combined scores for ease of use and fit to vehicle. We found the Combi's handle difficult to move, and the Discovery was harder for us to disengage from its base than the other seats. (See the Ratings.)
The Discovery was also the only seat in our tests that had a three-point harness and lacked an adjuster to change the angle of recline of the base. (A newer model, the Discovery 5, adds a safer five-point harness but also lacks a base adjuster.) That made it more difficult for us to achieve a suitable angle of recline when we installed the seat in our five test vehicles. Babies in infant car seats must recline enough so that their head doesn't tilt forward, possibly obstructing their airway, according to the National Highway Traffic Safety Administration, the government agency that regulates car seats sold in the U.S. But if the seat leans too far back when installed, infants can be injured or ejected in a crash, NHTSA says.
Manuals for some of the seats we tested say that a positioning device may be needed to achieve a suitable angle of recline. The Discovery's manual, for example, notes that in some vehicles it may be necessary to place a tightly rolled towel or small blanket underneath the front edge of the base to provide enough recline for an infant's head to lie back comfortably. Indeed, for our fit-to-vehicle test we had to use a positioning device with the Discovery in all of our test vehicles; no other model required a positioning device. We think a base adjuster that is integral to the car seat generally makes the seat easier to install appropriately.
It is critical that you read, understand, and follow all manufacturer instructions so that you use the car seat correctly and your baby is comfortable and secure. Many details are unique to the specific model you own. For example, parents may know to adjust the harness as their child grows, but some seats also require you to change the position of the crotch strap or the seat may not perform as designed. The key point is that, in contrast to some other consumer goods, infant car seats are not the type of product where you can get by without instructions and wing it on your own.
As this report went to press, the Combi Centre ST, Compass I410, and Safety 1st Designer were to be updated along with the Evenflo Discovery, though the tested models are still available. In our ongoing evaluations of car seats, we will test those and other new models.
No matter which car seat you choose:
- Try out the seat you buy. If it doesn't fit securely in your car, return it for another.
- To make sure your car seat is positioned correctly in your vehicle, consider getting a free car-seat inspection. For a site
near you, go to www.nhtsa.gov.
- Adjust the seat as your child grows.
- Position your child in the center-rear seat of your car if the car seat can be securely fastened there.
- Remember that any car seat is better than no car seat at all.
