Courtesy of the Canada Safety Council

Rear-Facing Infant Seats
Infants under 9 kg (20 lbs.) do not have the muscle strength in their back and neck to travel safely in the forward-facing position. This level of development is generally achieved when they can sit up unaided for some length of time. If you are unsure, consult your pediatrician. The infant seat is positioned to face the rear of the vehicle, is used in a semi-reclined position and is fastened into the vehicle by the seat belt to prevent it from moving during an impact or sudden stop. In a crash, the forces of the impact are spread evenly across the strongest part of the baby's body and are absorbed into the back of the infant seat. Most infant seats are designed to hold babies from birth to 9 kg (20 lbs.), others to 7.9 kg (17 lbs.). The statement of compliance label affixed to the seat states the size of child for which the seat is designed. 

Never place a rear-facing infant seat in a seating position equipped with an air bag.

Combination Seats (Rear and Forward-Facing) 
Combination or convertible seats can be used rear-facing for the infant and then turned forward facing when the child is older. Generally, combination seats are designed to hold children from birth to 18 kg (40 lbs.). 

When a combination seat is used as an infant seat (from birth to approximately 9-kg), it faces the rear of the vehicle. Several recline positions may be available, so check the manufacturer's instructions for a position suitable for your vehicle. 

Check the instructions provided by the child car seat manufacturer for specific weight and height guidelines. In most cases, children are ready to be turned forward facing once they reach the maximum limits stated by the manufacturer. However, before turning the seat to face the front, ensure the child is able to sit up well unattended. This stage of development indicates that the child's neck and back muscles are normally strong enough to withstand the stresses that are experienced during a collision or sudden stop when forward facing. If you are unsure, consult your pediatrician. 

Forward-facing child car seats must be anchored to the vehicle by a tether strap, which prevents the seat from bending or pitching forward or sideways in a crash. The tether strap is fastened to the top of the child restraint and hooks onto an anchor bolt assembly installed in the metal framework of the vehicle. It must be installed exactly according to the child car seat manufacturer's instructions. Check your vehicle owner's manual for information on installation locations in your particular vehicle. 

Booster Seat
Booster seats are for children who weigh between 18 and 27 kg (40 to 60 lbs.) and are not yet ready for a regular lap or lap-shoulder belt. The booster seat is a firm cushion with a retaining system for holding the seat belt in a position low and snug over the child's lap and the shoulder belt across the child's chest. Household booster seats are not intended for use in vehicles, so check the compliance label to ensure the seat you choose meets Canada Motor Vehicle Safety Standards. 

Children will outgrow the booster seat when the mid-point of their ears reaches above the top of the vehicle seat back, or when they exceed the manufacturer's height/weight limits. The child must then wear a regular seat belt. 

Seat Belt Assembly
When a child is ready to use the vehicle seat belt system, take the time to explain how it should be worn properly. To prevent injury, lap belts should be worn snugly and as low on the hips as possible. The shoulder harness should not lie across the child's face or neck. Never place the shoulder-belt portion of a lap/shoulder belt assembly under a child's arm since this could crush the rib cage during impact. Seat belt adjustors are also available to adjust the shoulder harness to fit a child. If necessary, use the middle rear seat of a vehicle since it is usually only equipped with a lap belt. 

Helpful Hints
When the vehicle is in motion and the child car seat is not being used, it should be buckled in by the seat belt to prevent it from flying into someone in the event of a sudden stop. 

When a child is traveling in a child car seat, make sure the straps are adjusted so they fit snugly for his/her size. If the harness is too loose, the child may slip out. The straps also may need adjusting if the child is dressed in bulky winter clothing. 

The preferred location for a child car seat is the rear centre passenger seat, as it offers maximum safety from intrusion in a collision. However, if you are traveling alone with a child, the seat may be placed in the front passenger seat so that your attention is not diverted from the road to attend to the youngster. 

A rear-facing infant seat must never be placed in a seating position where an air bag is installed.

This Article courtesy of the Canada Safety Council.