Using the Lab to Improve Tools for Child Restraint System Safety Design

May 7, 2013

Moderator Note: In today’s post we feature the words of Matthew R. Maltese, PhD, a biomechanical research engineer who is leading a multi-year research study at CHOP sponsored by the Center for Child Injury Prevention Studies (CChIPS) to determine the differences between the Federal Motor Vehicle Safety Standard (FMVSS) 213 regulatory bench sled test and real vehicle seats. This FMVSS 213 test helps manufacturers ensure their child restraint systems, such as rear- and forward-facing child safety seats and booster seats, meet minimum standards of performance in crashes. Matt has been sharing the progress of his work in engineering and traffic safety conferences and is currently publishing the results.


Crash test with actual vehicle rear seat

I recently received practical questions from an audience of Child Passenger Safety (CPS) technicians about how they should share with parents the results of my ongoing research. The short answer is: continue to educate parents exactly as you have been doing using current National Highway Traffic Safety Administration (NHTSA) guidelines. Child safety seats and booster seats, as they are, are very effective at protecting children in crashes. The risk of serious injury for crash-involved children (ages 0-8 years) using age-appropriate restraints is less than one percent. Until all preventable injuries have been eliminated, researchers, manufacturers and regulators will strive to continue to reduce that risk. One way is to improve the tools we use to design child restraint systems. This is a goal of our current research at CHOP.

A Dynamic Comparison of the FMVSS 213 Bench with Vehicle Rear Seating Systems

With a vision for zero preventable fatalities and injuries, our research group at CHOP embarked on a multi-year research project to examine one component of the multi-faceted child safety system – the FMVSS 213 regulatory sled test used to evaluate rear- and forward-facing child safety seats (CSS) and booster seats in North America. This dynamic sled test simulates a frontal vehicle crash in which CSS are restrained on a bench seat intended to mimic the rear seat of a vehicle. Our methods were straightforward. We installed the same CSS or booster seat with an age-appropriate crash test dummy on the regulatory test bench and on each of three actual motor vehicle seats with their respective seat belt systems extracted from a sedan, SUV, or minivan. We then compared the motion of the CSS/booster and crash test dummy between the sled test bench and each of the three vehicle seats. In this way, the dummy and CSS’ kinematics provide one measure of the differences, if any, between how a CSS performs on the test bench as compared to vehicle seats. As our community seeks further reductions in mortality and morbidity, we must revisit and refine the design tools we use to build our safety systems. Thus, the potential differences between the performance of CSS on actual vehicle rear seats and the regulatory tests should be explored because improvements in the test protocol may lead to improvements in the effectiveness of future CSS and booster seat design. We anticipate completing our analyses within the next few months and will share our results as soon as they are published.

What Do Potential Differences In Performance Mean for CPS Education?

At this stage, these results have no immediate implications for current child passenger safety education. Rather, they are meant to inform the development of the next generation of safety seats that will provide even better protection for our children. While these data provide valuable insight into CSS performance, we look forward to additional data generated by us and others that will build upon these initial findings and move us closer toward finding ways to improve the performance of CSS. CPS technicians and instructors already provide phenomenal information and resources to families and should continue to do so using current guidelines. Data from the past 10 years show that contemporary CSS designs developed from current test protocols can be considered a child safety success story.