That’s because the National Highway Traffic Safety Administration has yet to develop a lifelike child crash test dummy that can accurately ensure that seats for heavier children provide the protections promised.
Problems with developing child dummies are also a key reason why seats for all children have no federal requirements for effectiveness in side-impact, rear-end and rollover collisions, car seat experts said.
Parents are confronted with a barrage of safety seat choices for children of all sizes. More than 100 models for infants, toddlers and older children are on the market, according to CarseatBlog.com, which is written by parents and car seat experts who monitor the industry. Many parents say they find little information about seats beyond what they cull from private testing organizations, such as Consumer Reports magazine and the Insurance Institute for Highway Safety.
“I think everyone is a little unclear about it, especially the booster seat issue,” said Rosemary Berger of Rockville, as she watched her 4-year-old son, Ryan, at the play area in Bethesda’s Westfield Montgomery shopping mall. “It’s hard to understand what’s required and what’s been tested.”
Berger said she bought a backless booster seat for Ryan after he reached 40 pounds. “But I’m not convinced yet whether he’s safe in that,” she said.
Sara Keleher of Bethesda said she did plenty of Web research before choosing seats for her 2-year-old and 2-month-old daughters. Still, she said she was not aware that federal regulations do not cover all seats or all types of crashes.
“I’m under the assumption that there’s some federal guidelines that companies have to meet,” Keleher said.
Car seat manufacturers “self-certify” that their seats meet the safety standards that do exist. The NHTSA tests 75 to 90 models each year, said Ronald Medford, the agency’s deputy administrator. Those that do not comply with federal rules are recalled.
The NHTSA only tests for crash protections that are regulated. That leaves parents to rely on manufacturers’ assurances for the higher weight seats and for side-impact protections, seat-belt fit and other potential injury factors.
Delay in oversight
Safety experts say a lack of funding for researching and developing lifelike child test dummies has caused the NHTSA’s oversight of safety seats to lag years behind in a highly competitive industry that evolves to meet demand.
Car seats with harnesses designed just a few years ago to hold children who weigh up to 65 pounds are now marketed for up to 85 pounds. Manufacturers say they are catering to parents of overweight children, some who reach 40 pounds by 21
2 years old — too young and often too short for the next step, a belt-positioning booster seat.
Parents also are seeking harness seats for older disabled children and are responding to experts’ findings that harnesses distribute crash forces more evenly than seat belts, industry observers said. Booster seats designed to help properly position adult-size seat belts on children’s smaller frames are marketed for up to 120 pounds.
Critics say the lag in government oversight has left some higher-weight seats vulnerable to being used incorrectly. The NHTSA has not determined whether seats for children 65 pounds and over could overload vehicles’ LATCH anchor and tether restraint systems. The LATCH (lower anchors and tethers for children) systems, installed in new vehicles since 2002, were designed to secure safety seats holding children 48 pounds or less, according to automakers.
A dummy to mimic a 10-year-old’s body was supposed to be developed by late 2004 as part of the federal Anton’s Law, enacted in 2002. Anton Skeen was 4 years old and nearly 50 pounds when he died in 1996 after being ejected from his seat belt in a rollover crash in Washington state. His mother, Autumn Alexander Skeen, has since advocated for state booster seat laws and the federal law, which mandated child-restraint performance requirements for children over 50 pounds.
Skeen said she is disappointed that those requirements have been delayed, because the 78-pound dummy is still in development nearly a decade later. Anton’s Law required the dummy to be developed within two years as a way to test whether manufacturers were complying with new requirements.
“There’s not enough guidance” for parents shopping for belt-positioning booster seats, Skeen said. “Parents are looking at things like cup holders. They’re not coming to it looking at the correct way for the shoulder belt to cross the clavicle.”
Safety advocates and child seat researchers say they have not noticed any problems with higher-weight seats in real-world crashes. Most say they are focused on persuading all parents to use child safety seats and teaching them how to do so correctly.
Safety seat use led to a 71 percent drop in infant deaths and a 54 percent reduction in crashrelated fatalities for 1-to-4-year-olds, according to NHTSA statistics comparing 1988 and 1994 crash data.
Lorrie Walker, a car seat specialist for the nonprofit Safe Kids advocacy group, said car seat makers’ concerns about fending off costly recalls and lawsuits give them incentives to make internal testing robust.
“We’re not seeing large numbers of kids affected by shoddy products,” Walker said. “When used properly, we know kids [in child restraint systems] do extremely well in crashes.”
Still, researchers who study the impacts of motor vehicle collisions on children say the pace of dummy development has complicated efforts to make all seats as safe as possible. Motor vehicle crashes are the leading cause of death for children 3 to 14, according to the NHTSA: Of the 322 children 4 and younger killed in collisions in 2009, 229 were in some kind of restraint. Researchers say many children killed in car seats or boosters are in crashes considered catastrophic or in restraints that were seriously misused.
NHTSA officials say they cannot impose protection standards before they have test dummies that can accurately determine whether manufacturers are meeting them.
In November, the NHTSA made its third attempt since 2005 to propose safety standards for seats aimed at children over 65 pounds. However, the agency has a major problem: The 10-year-old dummy’s spine is stiffer and its chest much harder than an actual child’s. That causes the dummy’s head to snap down so that its chin hits its overly hard chest, resulting in unacceptably high crash forces on the dummy’s head. NHTSA officials say studies of real-world collisions show that restrained children’s head injuries stem most often from their heads hitting the seat back.
“We don’t have any data of children in crashes where they’re hurt from the chin going into
the chest,” said David Campbell,
a Cleveland-based technical
consultant to the Juvenile Products Manufacturers Association, which represents safety seat makers. “It’s just not there, but this dummy is doing that.”
The NHTSA has proposed setting some standards for the higher-weight seats, including regulating how well they remain intact and absorb overall “crash energy.” But because of the unrealistic chin strikes, the NHTSA has proposed delaying standards for the amount of crash forces permitted on the child dummy’s head until its “biofidelity” can be improved. It also has postponed rules for proper seat belt fit on booster seats, saying the type of seat belt test it evaluated did not produce reliable results from one lab to the next.
Medford said the NHTSA hopes to have safety standards for higher-weight seats finalized this year and the dummy’s flaws corrected in 2013. Medford said the agency also is working on a child-size dummy to use in side-impact tests. Such collisions account for one-third of all fatalities in child restraints.
“This administration is clearly interested in getting this issue resolved,” Medford said. “It’s taking longer than we’d like. We would really like to see improvements to the dummy so we can use it to its fullest potential.”
The American Academy of Pediatrics has asked the NHTSA to prioritize fixing the dummy to allow regulators to test for crash forces on the head. Measuring those forces is critical to monitoring for serious or potentially fatal injuries, said Marilyn Bull, a medical director and car seat specialist for the Automotive Safety Program at Riley Hospital for Children at Indiana University Health.
“The head flops farther forward on a child,” Bull said. “You’ll get spinal fractures, paralysis and even death.”
‘Not just little adults’
The difficulty in developing sophisticated child test dummies dates to the late 1970s, when states began requiring that children, who were held in laps or left to slide across seats, be secured in specialized restraint systems.
Adult-size dummies are based on 40 years of research, including data from actual collisions and crash tests using adult cadavers. However, researchers said, children are in vehicles less often than adults and, in turn, are involved in far fewer collisions. That leaves less real-world crash data to help determine how much force their bodies can tolerate before injuries occur. Car seat researchers said dummy designers have been reluctant to use children’s cadavers for tests.
Without that information, researchers said, child dummies have been designed primarily by scaling down adult dummies and using medical data from living children. Developing a lifelike dummy whose test results can be replicated can take decades and cost several million dollars, researchers said.
“We know kids are put together differently,” said Kristy Arbogast, engineering director for the Center for Injury Research and Prevention at Children’s Hospital of Philadelphia. “They’re not just little adults. They’re different mechanical structures. . . . NHTSA doesn’t have the money to fund all the research we need” to develop accurate dummies.
Campbell, of the car seat manufacturers group, said companies would welcome a dummy that could enforce safety standards for the higher-weight seats. Until then, he said, manufacturers will continue their tests to ensure that even seats that are not regulated do what they promise, to protect children and ward off recalls and lawsuits.
“Believe me,” Campbell said. “The manufacturers are very careful to make sure these seats meet their expectations.”
Staff researcher Magda Jean-Louis contributed to this report.