When Children Should Use Booster Seats - Lincoln 2009 MKS Owner's Manual

Seating and Safety Restraints
Booster seats position a child so that vehicle lap/shoulder safety belts fit
better. They lift the child up so that the lap belt rests low across the hips
and the knees bend comfortably at the edge of the cushion, while
minimizing slouching. Booster seats may also make the shoulder belt fit
better and more comfortably. Try to keep the belt near the middle of the
shoulder and across the center of the chest. Moving the child closer (a
few centimeters or inches) to the center of the vehicle, but remaining in
the same seating position, may help provide a good shoulder belt fit.

When children should use booster seats

Children need to use booster seats from the time they outgrow the
toddler seat until they are big enough for the vehicle seat and
lap/shoulder belt to fit properly. Generally this is when they reach a
height of at least 4 feet 9 inches (1.45 meters) tall (around age eight to
age twelve and between 40 lb (18 kg) and 80 lb (36 kg) or upward to
100 lb (45 kg) if recommended by your child restraint manufacturer).
Many state and provincial laws require that children use approved
booster seats until they reach age eight, a height of 4 feet 9 inches
(1.45 meters) tall, or 80 lb (36 kg).
Booster seats should be used until you can answer YES to ALL of these
questions when seated without a booster seat:
• Can the child sit all the way back
against the vehicle seat back with
knees bent comfortably at the
edge of the seat cushion?
• Can the child sit without
slouching?
• Does the lap belt rest low across the hips?
• Is the shoulder belt centered on the shoulder and chest?
• Can the child stay seated like this for the whole trip?
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