Question 1

What steps need to be taken to correctly harness?

Accepted Answer

https://www.youtube.com/watch?v=Gp5TQRmhCAs

Question 2

What are the risks of incorrect chest clip placement?

Accepted Answer

The chest clip should be properly placed so it can do its job - which is to keep the shoulder harness properly placed pre-crash. If it's too low, especially in conjunction with a loose harness, the child can be ejected. It's a myth that a low chest clip causes internal injuries in and of itself.
 
Line up the clip so that the top of it lines up with the top of the armpits.
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A five point harness distributes force evenly across the body, there aren't pressure points that will cause injury if it is used properly.

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