• Always follow manufacturer instructions.
6. How should a lap belt fit?
The lap belt should fit low over a child's upper thighs. Make sure the child sits straight against the seat back. Keep the belt snug. If the lap belt rides up onto the tummy, it could cause serious injuries in a crash.
7. How can you make a shoulder belt fit better?
The shoulder belt should stay on the shoulder and be close to the child's chest.
• If you have the kind of shoulder belt that stays loose when it is pulled out, make sure there is no more than one inch of slack. Too much slack will prevent the belt from working well. Teach your child to tug at the shoulder belt to take up excess slack.
• If the shoulder belt fits so poorly that it goes across the neck or face, raise the child with a belt-positioning booster.
Never put a shoulder belt under the child's arm or behind his or her back. Either of these kinds of misuse could cause serious injury in a crash.
Warning: Some devices advertised to improve belt fit for older children and adults are not covered by government standards. They may help with shoulder belt comfort but could also put too much slack in the shoulder belt or cause the lap belt to ride up. Boosters are a better solution for children who fit in them.
From the National Highway Traffic Safety Administration. Learn more about booster seats by checking out the NHTSA's FREE brochure, A Parent's Guide to Buying and Using Booster Seats.