Rear-Facing Down Under


The Importance of correct strap placement

Posted on December 23, 2013 at 11:15 PM

The Importance of correct strap placement.

The in-built harness straps on your child’s car seat are your child’s safety net in a car crash. If the straps are not positioned correctly over the child’s shoulders, straight and snug, they CANNOT do their job of keeping your child safe in a crash. You wouldn’t jump onto a safety net that wasn’t secured correctly, so you cannot expect your child to be protected by straps that are not positioned correctly.

In the event of a car crash, everything inside the car that is not restrained is thrown violently forwards upon impact. The harness straps are designed to prevent your child’s body from hitting objects within the car or from being thrown from the car.


If a child takes their arms out of the straps, this leaves them with NO upper body support in a crash. Their upper body would fly forwards, their head hitting the front seat, the door or even the roof. They would be at risk of head injuries, spinal injuries and internal injuries. In a worst case scenario, the child could also be ejected from the car.

Crash Test: Arms out of harness straps


Loose and twisted straps cannot protect a child effectively in a crash. With the straps too loose, the child will be subjected to too much forward movement of the upper body and head. The straps can slip off the shoulders, rendering them useless. Twisted straps will not distribute the crash forces evenly, thus causing too much pressure on the child’s delicate body.

Crash Test: Correct VS incorrect strap placement and installation

Crash Test: Tight harness straps VS loose harness straps 

Crash Test: Correct harness slots VS incorrect harness slots 

The harness straps are designed to be worn straight and snug over the child’s shoulders and buckled in correctly on EVERY trip, no exceptions. Combined with a correctly installed seat, your child will have the best chance of surviving a car crash without sustaining life threatening or fatal injuries. To check that the straps are snug enough, you should not be able to pinch them vertically between your thumb and forefinger at the collar bone. Bulky clothing or thick coats should NOT be worn under the harness straps as this will leave the straps too loose in a crash. Blankets or coats should be placed OVER the top of the tightened straps for warmth in colder months.

Video: Danger of winter coats in car seats


Rear-facing is the safest way for young children to travel for as long as possible. It provides the gentlest way for them to ride down a crash and protects their immature, developing skeleton, heavy head and spine.  

Crash test: Rear-facing VS forward-facing & incorrect seatbelt placement

Forward-facing convertible booster seats with an in-built (not add-on) harness are best suited for OLDER children who have completely outgrown 0-4 years rear-facing/forward-facing car seats. The in-built harness straps provide better protection to children who are still too small and immature to use a booster seat with an adult seatbelt. When worn correctly the in-built harness spreads the forces of the crash to the child’s stronger bony parts of the skeleton (the shoulders and hips), rather than the soft abdominal area which can occur when small children use an adult seatbelt that is too big for their body.


Children MUST use a car seat with an in-built (not add-on) harness until they are 4 years old at the very MINIMUM. Keep children in a car seat with an in-built harness (not add-on) for as long as they still fit, even over the age of 4, to give them better protection in a crash.

Video: Australian Road Rules Child Restraints


To calculate the crash forces on unrestrained objects, multiply the weight of the object by the speed travelled at the time of the collision. So an unrestrained 20kg child, travelling at 60km/hr would become a 1200kg (1.2 Tonne) missile in a crash.

Correct shoulder strap postion for Australian child restraints:

For rear-facing, the harness straps should be positioned in the slots at or slightly above your child’s shoulders and never below their shoulders.

For forward-facing, the harness straps should be positioned in the slots nearest your child’s shoulders, but not more than 2.5cm above or below their shoulders.

H-Harnesses no longer recommended study

Categories: Educational Info