<Li> Booster seats - The earlier described combination seat can become a high - back belt - positioning booster . There is also a high - back belt positioning - booster that is available for that purpose only . The other type of belt - positioning booster is the low - back or no - back booster . The major differences between the low - and high - back booster seats are head support and improved protection in side - impact collisions . Vehicles with a bench seating and no headrest are required to use a high back booster . The purpose of the booster seats is to provide elevation to the child so the shoulder belt rests appropriately on the shoulder blade and does not ride up the child's neck . It also provides "hips" that the seat belt can rest securely across and remain on the large bones of the child instead of resting across the soft tissue of the abdomen . This seat is available for children over 40 pounds (18 kg) up to over 100 pounds (45 kg). From the ages of eight to twelve, children may have outgrown their booster seats and can be permitted to use regular adult seat restraints . It is suggested that, until the age of thirteen, the child remains in the back seat . </Li> <P> Manufacturers have quality controls to ensure seats are properly put together and packaged . However, it is not guaranteed that the included instructions are always adhered to and correctly followed . Up to 95% of the safety seats that are installed may not be the right seat for the child, may be hooked into the vehicle loosely, may be hooked with an incompatible belt in the vehicle, may have harnesses incorrectly fastened in some way, or may be incorrectly placed in front of air bags . In 1997, six out of ten children who were killed in vehicle crashes were not correctly restrained . </P> <P> Along with the problem of instructions not being followed properly, there are other hazards that can affect children involving these safety seats . A recent study attributed many cases of sudden infant death syndrome (SIDS) to the prolonged sitting or lying position these infants are in when putting the safety seats to use . When researchers reviewed more than 500 infant deaths, it was found that 17 of these deaths occurred while the infant was in a device such as a child safety seat . The age of the most occurring rates of death by SIDS in a child safety device was found to be under one month, having six of the 17 deaths happen in this age group . Although SIDS has been found to be a high risk regarding child safety seats, a coroner in Quebec also stated that "putting infants in car seats...causes breathing problems and should be discouraged ." His warning came after the death of a two - month - old boy who was left to nap in a child safety seat positioned inside his crib rather than the crib itself . The death was linked to positional asphyxiation . This means that the child was in a position causing him to slowly lose his supply of oxygen . Coroner Jacques Robinson said it's common for a baby's head to slump forward while in a car seat that is not properly installed in a car and that can diminish a baby's ability to take in oxygen . "The car seat is for the car," he said . "It's not for a bed or sleeping ." Robinson added, however, he has nothing against car seats when they are properly used . The coroner said that it is common for a baby's head to "slump forward while in a car seat and that it diminishes oxygen". </P> <P> The American Academy of Pediatrics says to "make sure the seat is at the correct angle so your infant's head does not flop forward . Many seats have angle indicators or adjusters that can help prevent this . If your seat does not have an angle adjuster, tilt the car safety seat back by putting a rolled towel or other firm padding (such as a pool noodle) under the base near the point where the back and bottom of the vehicle seat meet ." Safety seats come with an instruction booklet with additional information on the appropriate angle for the seat . </P>

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