ARLINGTON, Va. — Boosters are better than they used to be at fitting lap and shoulder belts on 4- to 8-year-old kids to restrain them in a crash. So parents don't have to search as hard for a good fit for their child and vehicle. Most belt-positioning boosters, though, don't offer consistently good fit in all vehicles. This is the bottom line in the Insurance Institute for Highway Safety's third round of booster evaluations.
Researchers assessed the safety belt fit of 72 boosters, assigning the best ones the top ratings of BEST BET or GOOD BET because they correctly position belts on average booster-age kids in most vehicles. The worst performers are ones the Institute doesn't recommend because they do a poor job of fitting belts. A good booster routes the lap belt across a child's upper thighs and positions the shoulder belt at midshoulder.
The Institute doesn't conduct vehicle crash tests to evaluate boosters because boosters don't do the restraining in a crash. It's the fit of the belt that's important.
"For the first time top-rated boosters outnumber ones the Institute doesn't recommend," says Anne McCartt, Institute senior vice president for research. "Now more than ever manufacturers are paying attention to belt fit, and it's showing up in our ratings."
Twenty-one boosters are BEST BET models, and 7 earn GOOD BETs (see list below). Another 8 aren't recommended at all. This represents a market shift. Last year only 9 seats out of 60 the Institute evaluated earned BEST BET.
Even though poor performers make up a smaller percentage of boosters evaluated this year, 36 fall in the middle because they don't consistently fit belts well on most kids in most cars, minivans, and SUVs. Most of these are backless boosters with good lap belt scores but not good shoulder belt scores.
"Unlike the top performers, consumers can't assume boosters in the in-between group will work in every family vehicle. Some may be fine, but parents still need to try them out to see if the lap and shoulder belts fit their kids correctly," McCartt says. Obvious red flags are lap belts that ride up on the tummy and shoulder belts that either fall off the shoulder or rub against a child's neck. McCartt advises parents to keep looking until they find a booster that fits.
Institute engineers assess boosters using a crash test dummy representing an average-size 6 year-old. They measure how 3-point lap and shoulder belts fit the dummy in each of the boosters under 4 conditions spanning the range of belt configurations in a wide variety of vehicle types. A booster's overall rating is based on the range of scores for each measurement.
Good belt fit
Boosters elevate children so safety belts designed for adults will fit better. The lap belt should fit flat across a child's upper thighs, not the soft abdomen. Good boosters have belt-routing features that hold lap belts down and forward. The shoulder belt should cross snugly over the middle of the shoulder. Then it's in position to provide effective protection in a crash.
Poor belt fit
Not all boosters provide good belt fit. Here the lap belt is too high on the abdomen, and the shoulder belt is too too close to the neck.
Why fit matters
No federal standard dictates how a booster should position belts. The government's dynamic tests of crash performance don't measure what boosters are meant to do, and the National Highway Traffic Safety Administration only ranks boosters by how easy they are to use. Manufacturers crash test boosters, but these simulations don't tell parents how boosters will fit kids in their cars. Every state and the District of Columbia has a child restraint law, but they differ when it comes to booster-age kids. In 27 states and D.C., the laws cover kids until age 8, with exceptions for kids who are big for their ages.
The Institute in 2008 began evaluating boosters to help make selecting appropriate ones less of a guessing game. Since then some manufacturers have adopted the Institute's test protocol and booster seat fixture to help evaluate belt fit on the new boosters they're designing. Britax Child Safety Inc. is one. The North Carolina-based company has 1 BEST BET (Britax Frontier 85) and 1 GOOD BET (Britax Parkway SG) this year.
Belts do the main job of keeping kids in boosters safe in crashes, but belts along with vehicle seats are designed for adults, not children, so it's important for boosters to lift kids into position for lap/shoulder belts to provide proper restraint. Children 4-8 who ride in boosters are 45 percent less likely to sustain injuries in crashes than children restrained by belts alone.
Wider variety of seats
New this year to the BEST BET ranks are seats by Chicco, Cybex, Graco, Harmony, and The First Years. These manufacturers join Britax, Clek, Combi, Dorel, Evenflo, and Recaro, which had BEST BET boosters in Institute evaluations last year and have models in the latest round.
"Parents looking for top-rated seats now have more choices that include several affordable picks," McCartt says. "Consumers don't have to spend much money on a booster to get good all-around belt fit. In fact, shoppers can find several BEST BET boosters for $50 or less through online retailers."
Forty-nine boosters are carryovers from the Institute's 2009 ratings because they still are in production. These include 7 BEST BET models, 5 GOOD BET boosters, and 6 that aren't recommended.
It's clear that some manufacturers are taking the ratings to heart. Harmony Juvenile Products has 5 BEST BET boosters, more than any other manufacturer. One of them, the Harmony Secure Comfort Deluxe backless, wasn't recommended last year. The company modified it to eliminate the earlier problem with lap belt fit. Dorel Juvenile Group has 5 seats that rate either BEST BET or GOOD BET, including the new Safety 1st Boost Air Protect. The firm sells seats under the names Cosco, Dorel, Eddie Bauer, Maxi-Cosi, Safeguard, and Safety 1st. Dorel also makes 4 boosters the Institute doesn't recommend, down from 7 in the prior round of evaluations.
What should parents do if a booster they already have isn't one the Institute recommends using? McCartt advises parents in this situation to take note of how the safety belts in their vehicle fit their child next time they're in the car.
"If the booster isn't doing a good job — if the lap belt is up on your son or daughter's tummy or if the shoulder belt is falling off your child's shoulder — then find a replacement booster seat as soon as practical, but you'll probably want to keep using the old one until then," McCartt says.
2010 IIHS booster evaluation results
|Britax Frontier 85 (combination highback)|
|Chicco KeyFit Strada (dual highback)|
|Clek Oobr (dual highback)|
|Cosco Pronto (dual highback)|
|Cybex Solution X-Fix (highback)|
|Eddie Bauer Auto Booster (dual highback)|
|Evenflo Big Kid Amp (backless)|
|Evenflo Maestro (combination highback)|
|Graco TurboBooster Crawford (dual highback)|
|Harmony Baby Armor (dual highback)|
|Harmony Dreamtime (dual backless)|
|Harmony Dreamtime (dual highback)|
|Harmony Secure Comfort Deluxe (backless)|
|Harmony Youth Booster Seat (backless)|
|Maxi-Cosi Rodi XR (dual highback)|
|Recaro ProBOOSTER (highback)|
|Recaro ProSPORT (combination highback)|
|Recaro Vivo (highback)|
|Recaro Young Sport (combination highback)|
|Safety 1st Boost Air Protect (dual highback)|
|The First Years Pathway B570 (highback)|
|Britax Parkway SG (dual highback)|
|Combi Kobuk Air Thru (dual backless)|
|Combi Kobuk Air Thru (dual highback)|
|Evenflo Symphony 65 (3-in-1 highback)|
|Graco TurboBooster Sachi (dual highback)|
|Graco TurboBooster Wander (dual highback)|
|Maxi-Cosi Rodi (dual highback)|
|Eddie Bauer Deluxe (combination highback)|
|Eddie Bauer Deluxe 3-in-1 (highback)|
|Evenflo Express (combination highback)|
|Evenflo Generations 65 (combination highback)|
|Evenflo Sightseer (highback)|
|Harmony Baby Armor (dual backless)|
|Safety 1st All-in-One (3-in-1 highback)|
|Safety 1st Alpha Omega Elite (3-in-1 highback)|
|Note: Thirty-six boosters are in the middle range. They may provide adequate belt fit for some kids in some vehicles.|