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Harness Straps: How to Use Properly and Why They Are So Important

Harness Straps: How to Use Properly and Why They Are So Important

Car Seats
Harness straps play a crucial role in your child’s safety, but it can feel tricky to get them just right. Let’s take a look at how to fit them properly, as our CPST explains why they’re so important.

Harness straps are kind of a big deal when it comes to your child’s safety, yet using them improperly makes up a large percentage of car seat mistakes. In this edition of Diono Journal we ask our Child Passenger Safety Technician – CPST for short – to explain why they’re so important, how to fit them correctly, and common mistakes to avoid.

Until your Very Important Passenger graduates to a booster seat they’ll be traveling in a 5-point harness for quite some time. As the name suggests, a 5-point harness covers different areas of the body to safely restrain the child and spread crash forces evenly over the strongest parts of their body. How the harness fits on your child will depend on whether they’re rear-facing or forward-facing.

You’ll notice on your car seat a set of different slots for the harness straps to be threaded through. Which slots you use will determine where the harness straps should be positioned.

Depending on the height or weight of your child, they will travel either rear-facing or forward-facing. Children riding in a rear-facing car seat should have the harness straps located at or below their shoulders” says Scott, our CPST. “Children riding forward-facing will instead have the harness straps located above their shoulders.”

Threading the harness straps correctly ensures your child is properly protected in a crash. Let’s say that the harness straps are positioned too high when rear-facing. The result is similar to not tightening the straps at all. The most common collision is a rear impact, during which a child restraint system is designed to prevent the child’s body from sliding upwards in their seat, towards the point of impact.

If they are not harnessed correctly, they are more likely to accelerate upwards in their seat. As the child moves higher, the crash force against their head and chest increases both at the start of the collision and as they decelerate back into their seat.

Passengers traveling forward-facing require the harness straps to be above their shoulders as crash forces cause their body to be propelled forwards. Positioning the harness straps correctly enables them to effectively decrease the distance the child is thrown forwards, therefore limiting the force on their spine and shoulders.

In both modes of travel, ensure the harness straps are not twisted and are threaded entirely through both the shell and the fabric cover of the car seat. You’ll also want to perform what’s known as “The Pinch Test” to make sure the harness is tightened properly.

To perform the test, tighten the harness according to the directions in your manual. At your child’s collarbone, try to pinch the harness strap together using your forefinger and thumb. If you can pinch any of the webbing, continue to tighten until your fingers slide across the strap. Lastly, position the chest clip at arm pit level.

It’s also important to check for common mistakes before each journey to be absolutely certain everything is correct. Mistakes are easily made, but that doesn’t mean anyone is a bad caregiver! What matters most is checking for mistakes and being mindful to prevent them.”

Common car seat harness strap mistakes

  • Incorrectly routed through the car seat

Your car seat manufacturer has crash tested the seat under strict conditions where everything is fitted and configured correctly. Therefore, your car seat is only known to be effective when used correctly. Not routing the harness straps correctly can impact the performance of your car seat in a crash, while twisted straps can cause injury by not evenly distributing crash forces over your child’s body.

  • Wearing bulky clothing in their car seat

Remember the pinch test? Well, that’s only effective when the harness straps are as close to your child’s body as possible. Wearing bulky clothing such as winter coats interferes with the snugness of the harness straps, causing them to be too loose.

    • Harness straps are not positioned correctly

    As explained above, the position of the harness straps depends on how the child is traveling. If the child is rear-facing their harness straps should be at or below their shoulders. A simple way to remember this is that you should not be able to see the straps coming through the harness slot in the car seat. They should be almost hidden behind the child’s shoulders. This is because you don’t want the child to be able to “slide up” in a crash. Instead, the harness straps should be acting like a cradle to prevent any potentially dangerous movement in a crash.

    Forward-facing children should have their harness straps positioned above their shoulders to prevent their body from propelling forward in a crash.

    • Harness straps are too loose

    It’s a really common mistake for caregivers to think harness straps are too tight” says Scott. “If ever in doubt, use the pinch test to check. I often remind caregivers that the harness doesn’t need to be super tight, just snug without any slack. A snug harness strap is more likely to effectively keep your child seated in their seat during a collision.” Remember, bulky clothing will impact the snugness of the harness straps and compress in a crash, increasing the risk of the child being ejected from their seat in a crash.

    • Chest clip is not at armpit level

    A common car seat myth is that the chest clip is designed to keep your child restrained in their seat in a crash. Truth is, it's more likely to break or come undone during a crash, and that's totally normal! The chest clip is a pre-crash positioning device that positions the harness straps correctly over the shoulders. A chest clip that is too low could cause the harness straps to slip off their shoulders. A chest clip that is too high causes risk of injury to their neck. A properly positioned chest clip, which should be level with their arm pits, will make sure the harness straps function correctly and keep your kiddo seated safely and securely.