Running and playing with friends on a playground is most likely a part of all our childhood memories. They are a great place for kids to learn and grow and burn off some energy. However, playground falls/incidents are often one of the leading causes of ER visit for children when reviewing all unintentional injury risk areas.
Three factors affect playground safety more than any other:
Surfacing: It is important that all playgrounds, including those found at schools, parks and home be placed on at least 9-12" of proper surfacing. This would include substances such as rubber mulch, sand, pea rock or wood chips. This will cushion the fall from equipment, potentially preventing broken bones, concussions or other head injuries. Surfacing should extend at least 6 feet in all directions around the equipment. Watch for areas below equipment such as swings and slides that often get areas of displaced surfacing. Assure that these areas are filled in and kept to the 9-12" depth required.
Age appropriate equipment: Playgrounds are designed for children in two age groups, usually 2-5 and 5-12. Be sure that your children are playing on equipment that is designed for their age as these will limit their risks based on the height and width of bars, steps, and equipment.
Supervision: Make sure that playgrounds are used as they are intended for play. Often kids get "creative" and use the play sets in ways in which they were not made to be used, thus increasing the chance of injury.
Here are some other sources of information on playground safety.
The Consumer Product Safety Commission provides guidance and standards for playground equipment. The following are resources offered by this organization: