There are two different types of bed guard rails, though they both serve the same basic purpose. The first is the kind that are used for adults. These can be found on hospital beds, or in beds for the elderly or in nursing homes. They are typically metal rails that can be raised into position, or lowered out of the way. They help protect elderly adults from falling out of bed, and provide something for them to hold onto when trying to sit up.
However, that type of bed guard rails should not be used for children. They typically have large gaps in the railings which can allow a small child's head to become entrapped. This could lead to injury or worse. Additionally, the bed rails used by adults are usually built into the frame of the bed. Unlike baby bed rails, they are not removable.
For children, such as toddlers just making the transition from the crib to a 'big-boy' or 'big-girl' bed, you want to find a bed guard rail that has several safety features. First, look for ones that have protective padding around the frame. Additionally, you want one without any gaps in the frame that would allow a child's head to become trapped. Also, you want to find one that does not have any spots for little fingers to get pinched. Lastly, the baby bumpers should be such that can be removed once the child is old enough to stay in bed without the risk of falling out.
Just remember that bed guard rails for children should be kid-friendly, not the cold-steel contraptions found on hospital beds.
George - http://babybedrails.net - Baby Bed Rails