GMC 2001 C3 Owner's Manual page 54

The restraint manufacturer's instructions that
come with the restraint state the weight and
height limitations for a particular child restraint.
In addition, there are many kinds of restraints
available for children with special needs.
CAUTION:
Newborn infants need complete support,
including support for the head and neck. This is
necessary because a newborn infant's neck is
weak and its head weighs so much compared with
the rest of its body. In a crash, an infant in a
-
rear facing seat settles into the restraint, so the
crash forces can be distributed across the
strongest part of an infant's body, the back and
shoulders. Infants always should be secured in
appropriate infant restraints.
CAUTION:
The body structure of a young child is quite
unlike that of an adult or older child, for whom
the safety belts are designed. A young child's hip
bones are still so small that the vehicle's regular
safety belt may not remain low on the hip bones,
as it should. Instead, it may settle up around the
child's abdomen. In a crash, the belt would apply
force on a body area that's unprotected by any
bony structure. This alone could cause serious or
fatal injuries. Young children always should be
secured in appropriate child restraints.
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