What safety feature must be used for children under the age of 1 in a vehicle?

For children under the age of 1, the law requires the use of a rear-facing car seat. This safety feature is crucial because it provides optimal protection for an infant's head, neck, and spine in the event of a collision. In a rear-facing position, the car seat absorbs much of the crash force and distributes the impact more evenly across the child's body, reducing the risk of severe injury.

Current guidelines from safety experts, including the American Academy of Pediatrics, emphasize keeping infants in rear-facing car seats until at least the age of 2, or until they surpass the height and weight limits set by the car seat manufacturer. These recommendations are based on extensive research indicating that rear-facing seats significantly enhance safety for young children.

The other options, such as booster seats and front-facing car seats, are not suitable for infants under 1 year old. A booster seat is designed for older children who have outgrown their forward-facing seats and need help to ensure the seatbelt fits properly across their body. A seatbelt alone is not appropriate for infants, as they do not provide adequate protection without the appropriate car seat to restrain them properly.