65 is the new 70

Since 1970, the National Highway Traffic Safety Administration has been a driving force behind improvements to safety standards for automobiles.  The agency is constantly working to move safety standards forward and help keep all of us safer on the roads.  Developed in the 1970’s, the very first family of child-sized crash test dummies only included a 3 month old and a 3 year old dummy.  Since then, the family has grown to include a 6 year old dummy and now, a 10 year old dummy. 1

10 Year Old Dummy Impacts Weight Ratings for Car Seats

You may have noticed that the car seat you’ve been eyeing at the store has a new number at the end of the name. A number of seats that used to be rated to 70 pounds are now rated to 65 pounds so the seat names are being adjusted to have a 65 at the end instead of a 70.  Other seats are losing the number altogether.

Seat names are changing after changes to NHTSA testing requirements

Seat names are changing after changes to NHTSA testing requirements


The Short Version

This change comes as a result of the new testing requirements from the National Transportation Highway Safety Administration. NHTSA is now using a 77 lb, 10 year old dummy to crash test car seats with 65-80 lb weight limits and a 62 lb, 6 year old dummy to crash test car seats with 50-65 lb weight limits.

Note: the previous method tested all the way to those weights; it just used a different, smaller dummy.  So that older seat with the 70 lb rating is still rated to 70 lbs.

Some manufacturers have chosen to lower the limit on their seats rather than attempt to pass testing with the larger dummy.

Does this mean you’re getting less car seat for the money with a new 65 pound rated seat?  For most children, it does not.

In most cases, children will outgrow a harnessed seat by height before weight.  This was true before these new testing requirements and this remains true now.  These lower weight limits are closer to the actual proportional weights corresponding to the realistic height capacity of the seat.


Changes to Graco's seat names after the NHSTA testing requirement changes

Changes to Graco’s seat names after the NHSTA testing requirement changes

The Full Story

In order to achieve a rating of over 65 pounds, car seats must now pass testing with that 10 year old dummy. These dummies are taller than and have a higher shoulder height the 6 year old dummy that was previously used to test seats in this weight range.

NHTSA developed this test dummy in conjunction with new safety seat requirements including the changes to the LATCH limits, which also changed on the same day in February 2014.

The new dummy marks a significant step forward in child passenger safety testing; it allows researchers to capture new data points around the risk of injuries using head and knee excursions, and chest acceleration.  All of this adds up to better data being available as manufacturers work tirelessly to keep our Littles safer.

NHTSA describes the dummy as follows:

“FMVSS No. 2132 currently applies only to those child restraints for children weighing 50 pounds or less. However, studies have shown that children do not properly fit into the vehicle’s belt system until they weigh about 80 pounds. Further, an increasing number of child restraint manufacturers claim safe performance of some of their child restraints at weights beyond what is tested under FMVSS No. 213. The agency has been asked to consider using dummies weighing more than 50 lbs for compliance testing of these restraints. Currently, the Hybrid III 6-year old dummy weighs approximately 52 pounds.

In response to a growing concern for the safety of children, in the fall of 2000 the SAE began development of a dummy designed to represent the anthropometry of a ten-year-old child. The dummy, the Hybrid III 10-year-old child or HIII-10C, has been designed to weigh approximately 76 pounds with an estimated height of 4’6″.”

NHTSA's 10 year old crash test dummy weighs 76 pounds and is 4’6" tall

NHTSA’s 10 year old crash test dummy weighs 76 pounds and is 4’6″ tall

While the data from this dummy can help car manufacturers improve safety features for smaller passengers, the change has had an impact on the upper weight limits on many popular car seats.

Child Growth Statistics

The CDC growth chart for girls and  the CDC growth chart for boys, reveal similar results:

  • A child in the 50th percentile for weight would reach 60 lbs somewhere between ages 9 and 10
  • That same child  would reach 80 lbs somewhere between ages 11 and 12.

For this statistically average size of child, most harnessed car seats would be outgrown by height long before weight.

  • A child in the 95th percentile for weight would likely reach 60 lbs somewhere between ages 6 and 7 That same child would likely reach 80 lbs somewhere between 8 and 9 years old.

For this size of child, most harnessed car seats are still likely to be outgrown by height before weight.

In all of the above scenarios, only a child who was off-the-charts on the weight curve would need those extra pounds in a harnessed car seat.  Most neurotypical children can ride safely in a booster seat right around the time when they outgrow most harnessed car seats by height. That’s where the few seats with the 70, 80, or 90 pound weight limits continue to make great options.

These new testing regulations change very little for most children whose height and weight falls in the ranges listed on the CDC growth charts. In most cases, purchasing a car seat with a 65 lb weight limit is the same solid choice that it was before this change.  Some retailers still have 70 lb-rated seats on the shelves — if you find one of these, it will have a manufacture date from before  Feb 27, 2014.  This can often mean a bit of a bargain since the 70 lb limit seat may be marked down.  Seats with a 70 lb weight limit could still be used for a child at that weight, but as we’ve seen, very few children would still fit in the harness at that weight.

The addition of the 10 year old to the NHTSA crash test dummy family is a welcome one.  Though these lower weight limits are in some way a bit of a growing pain, the larger dummy represents yet another important step toward ensuring that all of our Littles ride safely.

Humanetics: History of Crash Test Dummies
2FMVSS 213 Regulation