When using a high chair, remember to:
Make sure the high chair cannot be tipped over easily.
If the chair folds, be sure it is locked each time you set it up.
Whenever your child sits in the chair, use the safety straps, including the crotch strap. This will prevent your child from slipping down, which could cause serious injury or even death. Never allow your child to stand in the high chair.
Do not place the high chair near a counter or table. Your child may be able to push hard enough against these surfaces to tip the chair over.
Never leave a young child alone in a high chair, and do not allow older children to climb or play on it because this could also tip it over.
A high chair that hooks onto a table is not a good substitute for a freestanding one. If you plan to use this type of chair when you eat out or travel, look for one that locks onto the table. Be sure the table is heavy enough to support your child's weight without tipping. Also, check to see whether your child's feet can touch a table support. If your child pushes against the table, it may dislodge the seat.
Additional Information from HealthyChildren.org: