Complex sentence: To reduce the risk of injury from falls, jungle gym areas often have a thick layer of woodchips or other impact-absorbing material covering the ground; the US National Safety Council recommends that playgrounds have at least 12 inches (30 cm) of such material.
Split into simpler sentences: To reduce the risk of injury from falls, jungle gym areas often have a thick layer of woodchips or other impact-absorbing material covering the ground. The US National Safety Council recommends that playgrounds have at least 12 inches (30 cm) of such material.