Chevrolet 2002 Astro Owner's Manual page 43

The lap part of the belt should be worn low and snug
3. To make the lap part tight, pull down on the buckle
on the hips, just touching the thighs. In a crash, this
end of the belt as you pull up on the shoulder part.
applies force to the strong pelvic bones. And you'd be
less likely to slide under the lap belt. If you slid under it,
the belt would apply force at your abdomen. This could
cause serious or even fatal injuries. The shoulder belt
should go over the shoulder and across the chest.
These parts of the body are best able to take belt
restraining forces.
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