Car seat design has come a long way over the years. One of the most recent advancements? Side-impact protection. As research has evolved and technology has improved, so have the safety standards designed to better protect children during some of the most serious types of crashes. In this article, we’ll walk through what side-impact protection is, how safety standards like FMVSS 213a came about, and what these updates mean for caregivers. What is Side Impact Protection in Car Seats? Side-impact protection refers to how a car seat is designed to help protect a child if a vehicle is struck from the side. In a side-impact crash, there’s less space between the point of impact and your child, which means the forces can reach them more quickly. Side-impact protection features are designed to help manage crash forces and provide added support for a child’s head and body during these types of collisions. At a high level, car seats help manage crash forces in a side collision through energy-absorbing materials, side walls, and head and torso support structures. These elements work together to help control movement and distribute crash forces in a way that supports the child’s body. The Importance of Side Impact Protection Side impacts are among the more common types of crashes and can be especially serious because of the limited space between the vehicle door and the passenger. Side-impact protection is designed to help: Manage occupant head movement during a crash Mitigate the side crash forces transferred to the child Provide containment and support around the occupant’s head and torso That said, side-impact protection is just one part of a complete system. Proper installation and fit are essential to how a car seat performs. Understanding Federal Safety Standards for Car Seats When you’re researching car seat safety, it’s easy to mix up federal standards and state laws. They’re related, but they’re not the same thing. State car seat laws determine how car seats are used. These laws vary by location. Federal car seat laws, on the other hand, set safety standards for car seats. These standards set the minimum performance requirements that every car seat sold in the United States must meet. They exist to help ensure a consistent level of protection across all products, regardless of brand. Federal car seat standards are established by the National Highway Traffic Safety Administration (NHTSA), which operates under the U.S. Department of Transportation. NHTSA develops these requirements using a combination of: Research and real-world crash data Controlled laboratory crash testing Ongoing review and updates as technology and data evolve As vehicle design changes and new crash information becomes available, federal standards are evaluated and updated to reflect the latest understanding of child passenger safety. Car Seat Standards & Testing: An Overview of FMVSS 213 FMVSS 213 (Federal Motor Vehicle Safety Standard No. 213) sets the minimum safety requirements for all child restraint systems (meaning car seats) sold in the United States. Historically, FMVSS 213 centered on frontal-impact crash testing. Car seats were required to demonstrate the ability to protect a child in a forward collision. Here’s how FMVSS 213 testing works: The car seat is installed on a standardized test bench that simulates a vehicle seat. A frontal crash is simulated at a specified speed and force. Crash-test dummies representing different child sizes are secured in the seat. During testing, FMVSS 213 evaluates: Head and knee movement Chest acceleration and injury criteria Structural integrity of the car seat during a crash Performance of harnesses, buckles, and attachment systems In its earlier versions, FMVSS 213 did not explicitly require a standardized side-impact crash test. Manufacturers could voluntarily design and incorporate side-impact features, but there was no federal side-impact performance requirement or uniform testing procedure. FMVSS 213a: Updated Car Seat Side Impact Protection Standards FMVSS 213a introduces a defined federal side-impact crash test for harnessed car seats for children up to 40 pounds, including: Infant car seats Convertible car seats All-in-one car seats Combination car seats, when used in harness mode In the FMVSS 213a side-impact test: A crash scenario is simulated in which a vehicle is struck from the side. A moving barrier is used to replicate another vehicle impacting the car. The evaluation focuses on how the child restraint manages forces coming from the side. FMVSS 213a measures: Head and lateral (side-to-side) movement during a side impact Injury criteria for the head and chest The interaction between the car seat, crash-test dummy, and a simulated vehicle door structure The standard is set to go into effect on December 5, 2026. Any car seat manufactured on or after that date that is made for sale in the US must meet these new side-impact requirements. That said, many manufacturers, including Chicco, have already incorporated side-impact testing and design considerations aligned with these updated criteria. Can I Keep Using My Current Car Seat? Yes, car seats manufactured before the FMVSS 213a effective date of December 5, 2026, can still be used as long as they are: Within their expiration date Have not been recalled Have not been involved in a crash Suitable for their child’s height and weight Installed correctly Find the Right Car Seat With Chicco Car seat requirements and design have never stood still, and side-impact protection is one example of how continued research helps shape the next generation of child restraints. As standards evolve, so does the commitment to creating seats that support children through every stage. At Chicco, safety is at the center of every car seat we develop. Explore our car seats today to find the right fit for your little one. FAQs What is side impact protection in car seats? Side-impact protection refers to the features in a car seat designed to help protect a child if a vehicle is struck from the side. This helps control how crash forces are absorbed and distributed. What are the new side impact car seat standards? The newest federal update (going into effect December 5, 2026) is FMVSS 213a, which adds a defined side-impact crash test for certain harnessed car seats. It establishes measurable performance criteria for how seats must manage forces in a side collision, including limits on head and chest movement and injury thresholds. What is FMVSS 213a? FMVSS 213a is a Federal Motor Vehicle Safety Standard issued by the National Highway Traffic Safety Administration (NHTSA). It builds on existing car seat regulations by introducing a standardized side-impact crash test. The goal is to ensure certain harnessed car seats meet specific performance requirements in simulated side collisions. Are booster seats included in FMVSS 213a? No, belt-positioning booster seats are not included in the FMVSS 213a side-impact testing requirement. FMVSS 213a applies to harnessed car seats for children up to 40 pounds, including infant, convertible, all-in-one, and combination seats when used in harness mode. For more guidance on choosing products and planning for each stage, explore our Baby Talk Blog.