General Car Seat Safety Tips: All children under 13 years of age should be placed in the back seat of the car, especially if you have passenger side air bags. Newborns, infants, and toddlers should be in a rear-facing infant only or convertible seat until they are 2 years old or have outgrown their rear-facing seat. Children who reach the max weight and height limits of their rear-facing seat before their second birthday would likely still be safer facing backwards, and should likely be moved into a rear-facing convertible seat with a higher weight and height limit. After they have passed their second birthday, toddlers can use a forward-facing car seat with harness straps, still in the back seat, until they outgrow it. Keep in mind that many car seats now have 50 to 70 pound weight limits, so kids can be in car seats with harness straps a lot longer than the old practice of switching to booster as soon as kids were 40 pounds. Children who have outgrown their car seat with harness straps should be placed into a belt positioning booster seat. You should not use your car's regular seat belts until they fit correctly, when your child is 4 feet 9 inches tall and are between 8 and 12 years old. Remember that your child will not be ready to use regular seat belts until the shoulder strap fits across the shoulder and not the neck, and the lap belt fits across the hips and not the stomach. Be sure to read the car seat manufacturer's instructions and your car owner's manual to be sure that you are installing and using the car seat correctly.
"Safety Tips for Child Car Seats"