Transport Canada has identified that many aftermarket products could be considered a safety risk when added to a child restraint system or booster seat.
The following is summary of some of the most common products that are not recommended for use:
Head Huggers or Head Support Cushions
These come with most infant car seats. If this half circle support cushion is attached to your car seat and can not move, then you may use it. If it is not and is just threaded through your harness system, it is recommended that you remove it. Instead, take two receiving blankets (one for each side of your child head), roll up, place beside the outsides of your carseat and have them curl in towards your baby's head like a candy cane. So this roll will be going up beside your baby's arms and shoulders and then filling in the gap on either side of your infant's head. This is the recommend method used to stabilize an infant's head in a car seat.
The reasons why the head huggers/support cushions are not recommended are because they add additional padding between your infant and the harness system . Also, rare case could fall behind your infants head causing their head to be stuck in a forward position, which could become a risk for suffication.
Any additional padding between the harness and your child,
such as Padded car seat bags, or bulky clothing
Your car seat harness has been designed to work your child and a minimial amount of clothing. This is the ideal. The reason for this is because in the event of a collisson, any padding or bulky clothing will compress to almost nothing causing significant room between your harness strap and your child. Hence your child will not be secured as tight as recommended and could lead to ejection of your child or other injuries.
Living in the Yukon we are not able to safely maintain this ideal all year round; therefore, we need to ensure that we are coming as close to the ideal as safely possible.