The problem is that many times these structures have no safe surfacing underneath and children fall from dangerous heights to hard surfaces. Inappropriate surface materials are asphalt, concrete, dirt and grass. Falls from one foot onto concrete can cause a concussion. Falls from eight feet unto dirt is the same as a child hitting a brick wall traveling 30 mph. Appropriate surfacing should be located directly underneath equipment and extend six feet in all directions, with the exception of slides and swings which have a longer use zone.
Swings have a use zone of twice the height from the ground to the crossbar, front and back.
The use zone for slides is the height of the slide plus four feet. Proper loose fill surfacing must be at the appropriate depth to cushion falls. An inch of sand upon hard packed dirt will not provide any protection. We recommend 12 inches of loose fill material under and around playground equipment. You should not be able to see concrete footings around any of the equipment.