Car Seats

4 Stages of Car Seats

Kate Nash

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If you are curious about the various stages or steps involved in safety car seats, I have prepared a comprehensive breakdown. It includes detailed information on each stage, including progression, age ranges, and more.

What are the four stages of car seat safety for kids?

The four stages of car seat safety for kids encompass a comprehensive approach to protecting children during car travel, ensuring their safety at each developmental stage. The initial stage involves rear-facing infant seats, specially designed to cater to newborns and infants. These seats provide crucial support to a baby’s fragile head, neck, and spine, distributing crash forces evenly and reducing the risk of injury in the event of a collision.

As infants grow, they transition to the second stage: forward-facing toddler seats. Typically around the age of two, children move into these seats, which feature harnesses to restrain them securely. The harness system is pivotal in distributing crash forces across the child’s stronger body parts, such as the shoulders and hips, offering enhanced protection during accidents.

Following the toddler stage, children progress to booster seats, marking the third stage of car seat safety. Booster seats are intended for children who have outgrown the forward-facing harness seats but are still too small to use adult seat belts effectively. Booster seats elevate the child, positioning them to ensure that the vehicle’s seat belt fits properly across their chest and hips, mitigating the risk of injury by preventing the belt from cutting across vulnerable areas.

Finally, as children continue to grow and mature, they advance to the fourth stage: using seat belts without additional restraint systems. This transition typically occurs around ages 8 to 12, depending on the child’s size and development. It’s crucial to ensure that the seat belt fits correctly, with the lap belt lying snugly across the upper thighs and the shoulder belt crossing the center of the chest and shoulder. Adhering to these four stages of car seat safety not only complies with regulatory standards but also prioritizes the well-being of children, minimizing the potential for injury and providing peace of mind for caregivers during travel.

stages of car seat progress over the years

Rear Facing:

Rear-facing car seat- 1st stage of car seat safety seat
Rear-facing car seat- 1st stage of car seat safety seat. Credit: NHTSA

At the Federal level, rear-facing seats are recommended for infants up to 2 years and AAP recommends keeping kids in the rear-facing seat for as long as possible or at least 2 years.

Different States, however, have different requirements with States like Alabama mandating rear-facing car seats for kids younger than one year old. It is important to note that there is some science to back up the recommendation to keep kids up to 2 years in the rear-facing seat.

Rear-facing car seats for infants and young children are crucial for their safety due to several technical reasons rooted in biomechanics and crash dynamics. The decision to position infants and young children in a rear-facing orientation is based on the understanding of how their bodies react to the forces exerted during a collision.

Below are the 5 reasons rear-facing seats are safer;

  1. Protection of Head, Neck, and Spine: The most significant benefit of rear-facing seats is the protection they offer to the child’s head, neck, and spine. In a frontal collision, the forces push the body forward, but the head and neck lag behind due to inertia. This can result in excessive strain on the neck and spine, potentially leading to severe injuries, especially in infants whose neck muscles are not fully developed. Rear-facing seats distribute the crash forces across the child’s entire back, reducing the risk of head and neck injuries by allowing the seat to cradle the child’s head and absorb the impact energy.
  2. Reduction of Crash Forces: Rear-facing seats allow for a larger area of contact between the child’s body and the car seat, which helps distribute crash forces more evenly. This reduces the pressure exerted on any single part of the child’s body, lowering the risk of injury.
  3. Protection from Intruding Objects: In the event of a crash, there is a risk of intruding objects entering the vehicle space. Rear-facing seats provide an additional barrier of protection for the child against such objects, as they are positioned further away from the point of impact.
  4. Alignment with Child’s Natural Physiology: Infants and young children have proportionally larger heads and weaker neck muscles compared to adults. Placing them in a rear-facing position aligns with their natural physiology and offers better support for their underdeveloped bodies during a crash.
  5. Reduction of Forward Motion: Rear-facing seats effectively counteract the forward motion of the child’s body during a collision, reducing the risk of secondary impacts with interior vehicle surfaces or other occupants.

Installing and use of rear-facing car seat – The basics:

using latch for rear-facing seat
  1. Choose the Right Seat: Select a rear-facing car seat that is appropriate for your child’s age, weight, and height, as well as one that fits your vehicle properly. Refer to the car seat manufacturer’s guidelines and your vehicle’s owner’s manual for compatibility and installation instructions.
  2. Positioning: Install the rear-facing seat in the back seat of your vehicle. Rear-facing seats should never be installed in the front seat of a vehicle equipped with an active passenger-side airbag, as this can pose a serious risk to the child in the event of deployment.
  3. Angle Adjustment: Ensure the car seat is reclined at the correct angle to support your child’s head and airway. Most rear-facing seats come with adjustable bases or built-in angle indicators to help achieve the proper recline angle. Follow the manufacturer’s instructions to adjust the seat to the appropriate angle.
  4. Secure Installation: Use either the vehicle’s seat belt or the LATCH (Lower Anchors and Tethers for Children) system to secure the car seat to the vehicle. Follow the manufacturer’s instructions and consult your vehicle’s owner’s manual to ensure correct installation. The seat should be tightly secured with minimal movement in any direction.
  5. Harness Adjustment: Position the harness straps at or below your child’s shoulders. The harness should fit snugly against the child’s body, with no slack or twists in the straps. Adjust the harness tightness to ensure a secure fit, with enough room for only one finger to fit snugly between the child’s collarbone and the harness strap.
  6. Chest Clip Placement: Position the chest clip at armpit level to keep the harness straps properly positioned on the child’s shoulders. Ensure the chest clip is securely fastened and snug against the child’s chest.
  7. Check Fit Regularly: Regularly check the fit of the car seat as your child grows. Adjust the harness straps, recline angle, and harness height as needed to ensure a proper fit and maximum safety.
  8. Follow Manufacturer’s Instructions: Always follow the manufacturer’s instructions and safety guidelines for installing and using the rear-facing car seat. If you have any questions or concerns about installation or use, consult the car seat manual or contact the manufacturer for assistance.

Before 2018, the AAP recommended that children could transition to forward-facing car seats. However, a study conducted by the AAP in 2018 led to a change in their recommendations.

The new recommendation now states that children should ride on rear-facing car safety seats for as long as possible, taking into account the limits of their car safety seat. This change applies to almost all children under 2 years old and the majority of children up to 4 years old. See the Report Summary here or read the Full Report here.

Check out infant car seat safety ratings. Note that the anti-rebound bar and load leg are some of the safety-enhancing features in infant rear-facing seats not available in the forward-seat stage.

Here is a detailed guide on reasons why we recommend extended use of rear-facing car seats.

Forward-facing:

Once your child reaches the maximum weight or height limit for a rear-facing car seat, it’s time to transition to a forward-facing car seat. This typically happens around age two, but always check the manufacturer’s guidelines for specific height and weight limits.

Forward-facing Car Seat - second stage seat
Forward-facing Car Seat

The transition from rear-facing to forward-facing car seats typically occurs around the age of two, but it’s essential to understand the factors that contribute to forward-facing seats becoming safer at this stage:

  1. Developmental Milestones: By the age of two, most children have developed stronger neck muscles, which can better support their heads in the event of a crash. This reduces the risk of excessive head movement and potential injury compared to younger infants who may have weaker neck muscles.
  2. Size and Weight Considerations: As children grow, they may outgrow the height or weight limits of their rear-facing car seats. Forward-facing seats often have higher weight and height limits, allowing children to remain in a five-point harness system for a longer period, providing optimal protection.
  3. Harnessing System: Forward-facing car seats utilize a five-point harness system, which distributes crash forces across the strongest parts of the child’s body, such as the shoulders and hips. This harness system offers robust protection and can effectively restrain a child during a crash, reducing the risk of injury.
  4. Impact Dynamics: In certain types of crashes, such as frontal impacts, a forward-facing orientation may offer advantages in distributing crash forces and reducing the risk of injury compared to rear-facing seats. However, it’s important to note that rear-facing seats still provide excellent protection in many types of crashes, especially those involving rear-end collisions or side impacts.
  5. Regulatory Standards and Testing: Car seat manufacturers design forward-facing seats to meet stringent safety standards and undergo rigorous testing to ensure their effectiveness in protecting children in various crash scenarios. These standards evolve over time based on research, technological advancements, and real-world crash data.
  6. Child Comfort and Compliance: Some children may find forward-facing seats more comfortable or enjoyable, leading to better compliance with car seat usage. When children are content and secure in their car seats, caregivers are more likely to consistently use them correctly, enhancing overall safety.

Based on the AAP Research in 2018, which resulted in a revision to the age requirement, the American Academy of Pediatrics now advises that children should continue to use a forward-facing car safety seat until they reach the weight and height limitations of that specific seat.

Many seats can safely accommodate children weighing up to 60 pounds or more. This updated recommendation eliminates the age requirement of using forward-facing seats up to 4 years, even though several US states still consider age as a determining factor for transitioning to different car seat types.

Basics of using and fitting Forward-facing car seat:

Installing and using forward-facing car seats correctly is crucial for ensuring the safety of toddlers and young children during car travel. Here are the basics of installing and using forward-facing seats:

  1. Select the Right Seat: Choose a forward-facing car seat that is appropriate for your child’s age, weight, and height, as well as one that fits your vehicle properly. Refer to the car seat manufacturer’s guidelines and your vehicle’s owner’s manual for compatibility and installation instructions.
  2. Positioning: Install the forward-facing car seat in the back seat of your vehicle. Ensure the seat is securely positioned and does not move more than one inch in any direction when properly installed.
  3. Harness Adjustment: Position the harness straps at or above your child’s shoulders. The harness should fit snugly against the child’s body, with no slack or twists in the straps. Adjust the harness tightness to ensure a secure fit, with enough room for only one finger to fit snugly between the child’s collarbone and the harness strap.
  4. Chest Clip Placement: Position the chest clip at armpit level to keep the harness straps properly positioned on the child’s shoulders. Ensure the chest clip is securely fastened and snug against the child’s chest.
  5. Secure Installation: Use either the vehicle’s seat belt or the LATCH (Lower Anchors and Tethers for Children) system to secure the car seat to the vehicle. Follow the manufacturer’s instructions and consult your vehicle’s owner’s manual to ensure correct installation. The seat should be tightly secured with minimal movement in any direction.
  6. Top Tether: Most forward-facing car seats come with a top tether strap that provides an additional anchor point to enhance stability and reduce forward movement in a crash. Ensure the top tether is properly attached to the designated anchor point in your vehicle and tightened according to the manufacturer’s instructions.
  7. Check Fit Regularly: Regularly check the fit of the car seat as your child grows. Adjust the harness straps, harness height, and recline angle as needed to ensure a proper fit and maximum safety.
  8. Follow Manufacturer’s Instructions: Always follow the manufacturer’s instructions and safety guidelines for installing and using the forward-facing car seat. If you have any questions or concerns about installation or use, consult the car seat manual or contact the manufacturer for assistance.

Check out the convertible car seat crash test results.

Belt-Positioning Booster Seats:

Belt-positioning booster seats serve as an intermediate step between forward-facing car seats with harnesses and using the vehicle’s seat belt alone. While both types of seats are crucial for child passenger safety, belt-positioning booster seats offer several advantages over forward-facing seats for older children:

Booster Seat - stage 3 car seat safety
Booster Seat
  1. Optimized Seat Belt Fit: Belt-positioning booster seats are designed to position the vehicle’s seat belt properly on the child’s body. They elevate the child, ensuring that the lap belt lies low across the hips and upper thighs, and that the shoulder belt crosses the center of the chest and collarbone without touching the neck or face. This optimal seat belt fit reduces the risk of injury in the event of a crash by distributing crash forces across the strongest parts of the child’s body.
  2. Freedom of Movement: Unlike forward-facing car seats with harnesses, belt-positioning booster seats allow older children more freedom of movement while still providing essential protection. This can lead to increased comfort for the child during car travel, promoting better compliance with seat belt usage.
  3. Ease of Use: Belt-positioning booster seats are typically simpler to install and use compared to forward-facing car seats with harnesses. They do not require adjusting harness straps or ensuring proper harness tightness, making them more convenient for caregivers, especially when transitioning between vehicles or between different children.
  4. Longer Usability: Belt-positioning booster seats have higher weight and height limits compared to forward-facing car seats with harnesses, allowing children to use them for a longer period as they grow. This extended usability makes belt-positioning booster seats a cost-effective option for families and ensures that children remain properly protected during the transition to using the vehicle’s seat belt alone.
  5. Versatility: Many belt-positioning booster seats can be used as either high-back boosters or backless boosters, providing versatility to accommodate different vehicle configurations and child preferences. High-back boosters offer additional support and protection for the child’s head and neck, while backless boosters are more compact and suitable for vehicles with high seat backs or headrests.

Here are the basics of installing and using belt-positioning booster seats:

  1. Select the Right Seat: Choose a belt-positioning booster seat that is appropriate for your child’s age, weight, and height, as well as one that fits your vehicle properly. Refer to the car seat manufacturer’s guidelines and your vehicle’s owner’s manual for compatibility and installation instructions.
  2. Positioning: Install the booster seat in the back seat of your vehicle. Ensure the seat is securely positioned and does not move more than one inch in any direction when properly installed.
  3. Proper Seat Belt Fit: The vehicle’s seat belt should fit your child properly when using a booster seat. The lap belt should lie low across the hips, touching the upper thighs, and the shoulder belt should cross the center of the chest and collarbone without touching the neck or face.
  4. Adjustable Headrest: Some booster seats come with adjustable headrests to accommodate children of different heights. Ensure the headrest is adjusted to the appropriate position so that the vehicle’s seat belt fits correctly and provides optimal protection.
  5. Backless vs. High-Back Boosters: There are two types of booster seats: backless boosters and high-back boosters. Backless boosters are suitable for vehicles with headrests or high seat backs, while high-back boosters provide additional support and protection for the child’s head and neck. Choose the type of booster seat that best suits your child’s needs and vehicle configuration.
  6. Secure Installation: If using a high-back booster seat, ensure it is properly secured to the vehicle using the LATCH (Lower Anchors and Tethers for Children) system or the vehicle’s seat belt. Follow the manufacturer’s instructions for correct installation and ensure the booster seat does not move more than one inch in any direction.
  7. Check Fit Regularly: Regularly check the fit of the booster seat and the vehicle’s seat belt as your child grows. Adjust the booster seat’s headrest and height position as needed to ensure a proper fit and maximum safety.
  8. Follow Manufacturer’s Instructions: Always follow the manufacturer’s instructions and safety guidelines for installing and using the belt-positioning booster seat. If you have any questions or concerns about installation or use, consult the booster seat manual or contact the manufacturer for assistance.

Vehicle Seat Belt:

The vehicle seat belt becomes a better option for older children when they have outgrown the belt-positioning booster seat and meet specific size and developmental criteria. Generally, this transition occurs when a child reaches the following milestones:

carseats-seatbelt - last car seat stage for kids
  1. Height and Weight Requirements: Children should transition to using the vehicle’s seat belt alone when they have reached the height of 4 feet 9 inches (about 145 cm) tall and weigh between 80 to 100 pounds (about 36 to 45 kilograms). At this size, they are typically large enough for the seat belt to fit them properly and provide adequate protection in the event of a crash.
  2. Maturity and Responsibility: Children should demonstrate maturity and responsibility to sit properly in the vehicle seat and wear the seat belt correctly at all times, without fidgeting or playing with the belt. They should understand the importance of wearing a seat belt and follow safety rules consistently.
  3. Proper Belt Fit: The vehicle’s seat belt should fit the child correctly, with the lap belt lying low across the hips and upper thighs, and the shoulder belt crossing the center of the chest and collarbone without touching the neck or face. The child should be able to sit comfortably with their back against the vehicle seat and their knees bent over the edge of the seat.
  4. No Slouching or Sliding: Children should be able to sit upright in the vehicle seat without slouching or sliding under the seat belt. Slouching can lead to improper belt positioning and reduced effectiveness in a crash.
  5. Understanding and Compliance: Children should understand the importance of wearing a seat belt and comply with safety rules consistently, without needing constant reminders or supervision from adults.

The Five-step Test:

The “Five-Step Test” is a simple assessment method to determine if a child is ready to transition from using a booster seat to using the vehicle’s seat belt alone. It helps ensure that the seat belt fits the child properly and provides adequate protection in the event of a crash. Here are the five steps involved in the test:

  1. Sit all the way back: The child should be able to sit all the way back against the vehicle seat, with their back against the seatback and their bottom against the seat cushion. Their knees should bend naturally over the edge of the vehicle seat without slouching or sliding forward.
  2. Feet flat on the floor: The child’s feet should be able to reach the floor comfortably and rest flat on the floorboards of the vehicle. If the child’s feet do not reach the floor, they may not be ready to use the seat belt alone.
  3. Knees bend at the edge of the seat: The child’s knees should bend naturally over the edge of the vehicle seat, without being elevated or resting against the back of the seat in front of them. This ensures that the lap belt can lie low across their hips and upper thighs, providing optimal protection.
  4. Shoulder belt fits across the shoulder and chest: The vehicle’s shoulder belt should fit snugly across the child’s shoulder and chest, without touching their neck or face. It should cross the center of the chest and collarbone and lie flat against the body.
  5. Stay seated properly for the entire trip: The child should be able to sit properly in the vehicle seat and wear the seat belt correctly throughout the entire trip, without slouching, leaning forward, or playing with the belt. They should understand the importance of wearing a seat belt and follow safety rules consistently.

Tips on Using Vehicle Seat Belt:

  1. Proper Positioning: Make sure the child sits all the way back in the vehicle seat, with their back against the seatback and their bottom against the seat cushion. Their knees should bend naturally over the edge of the seat, and their feet should reach the floor comfortably.
  2. Belt Fit: The vehicle seat belt should fit the child properly. The lap belt should lie low across the hips and upper thighs, not across the stomach, and the shoulder belt should cross the center of the chest and collarbone, not touching the neck or face.
  3. Use a Booster Seat if Necessary: If the child is too small for the seat belt to fit properly without a booster seat, continue using a booster seat until they meet the height and weight requirements and pass the Five-Step Test.
  4. Buckle Up Every Time: Teach children the importance of wearing a seat belt every time they ride in a vehicle, whether they’re sitting in the front or back seat. Make buckling up a habit from a young age to instill lifelong safety practices.
  5. Lead by Example: Set a good example for kids by always wearing your seat belt when driving or riding in a vehicle. Children are more likely to follow safety rules when they see adults modeling safe behavior.
  6. No Sharing Seat Belts: Remind children that seat belts are designed for one person only and should never be shared with another passenger. Each person in the vehicle should have their own seat belt for optimal protection.
  7. Stay Seated Properly: Encourage children to stay seated properly in the vehicle seat and wear the seat belt correctly throughout the entire trip. Discourage slouching, leaning forward, or playing with the seat belt, as these behaviors can compromise safety.
  8. Regular Checks: Regularly check the fit and condition of the seat belt to ensure it’s working properly and providing adequate protection. Replace any damaged or worn seat belts immediately.

Car Seat Belt Stages Progression Summary:

Here’s a detailed breakdown of the four stages of car seat usage for children, including the typical age range, recommended seat type, and key features of each stage:

Stage 1: Rear-Facing Infant Seats

  • Age Range: Birth to around 2 years old but can stay on up to 4 years as per AAP.
  • Seat Type: Rear-facing infant car seats.
  • Key Features:
    • Designed for newborns and infants, providing crucial support for their head, neck, and spine.
    • Harness system secures the child and distributes crash forces across the strongest parts of their body.
    • Should be installed at a reclined angle to support the child’s airway and prevent head flop.
    • Typically includes a removable carrier for easy transportation of the baby outside the vehicle.

Stage 2: Forward-Facing Toddler Seats

  • Age Range: Around 2 to 4 years old (or until the child outgrows the weight/height limits of the seat).
  • Seat Type: Forward-facing convertible or combination car seats with harnesses.
  • Key Features:
    • Designed to accommodate toddlers as they grow and gain more neck strength.
    • Utilizes a five-point harness system to secure the child and distribute crash forces across their body.
    • Higher weight and height limits compared to rear-facing seats, allowing for extended use.
    • Should be installed in a forward-facing position, following the manufacturer’s guidelines for recline angle and harness adjustment.

Stage 3: Booster Seats

  • Age Range: Around 4 to 8 years old (or until the child is large enough to use the vehicle seat belt properly).
  • Seat Type: Belt-positioning booster seats (high-back or backless).
  • Key Features:
    • Elevates the child to ensure proper seat belt fit, with the lap belt positioned low across the hips and the shoulder belt crossing the chest and collarbone.
    • Provides additional support and protection for the child’s head and neck, especially in high-back booster seats.
    • Helps transition the child from a harness system to using the vehicle’s seat belt alone.

Stage 4: Seat Belts

  • Age Range: Typically 8 years old and older, but depends on the child’s size and maturity.
  • Seat Type: Vehicle seat belt.
  • Key Features:
    • Child is large enough and mature enough to use the vehicle’s seat belt properly without additional restraint systems.
    • Lap belt should lie low across the hips and upper thighs, while the shoulder belt crosses the center of the chest and collarbone.
    • Child should be able to sit properly in the vehicle seat and wear the seat belt correctly for the entire trip.
car seat stages progression chart

Below is another chart by the CDC on car seat steps;

  • CDC Guide on booster seat chart

It’s important to note that these age ranges are approximate, and children may progress through the stages at different rates based on their size, weight, and developmental milestones. Always refer to the specific weight and height limits of each car seat, as well as the child’s readiness for transitioning to the next stage based on guidelines from the car seat manufacturer and child safety experts.

More resources: