"A two-year-old boy named Frank Nelson was climbing a 12-foot-tall slide in a Chicago park when he slipped through a railing and hit his head so hard that it caused permanent brain damage. The park system of Chicago was sued and had to pay out millions of dollars to Nelson’s family.
At that time, in the late 70s, there were no laws, or real industry standards when it came to the safety of playground equipment. Frank Nelson’s fall was one of a number of lawsuits that led the Consumer Product Safety Commission to publish the Handbook for Public Playground Safety in 1981. Then another standards organization, the ASTM, published its own guidelines. Pretty soon these rulebooks were in the hands of insurance companies and parks departments and school boards across the United States. To this day, almost all playgrounds have to be approved by a certified playground safety inspector.
And safety inspectors look for places where kids could fall, or get pinched, poked, or trapped. As you might imagine, all of these rules and regulations make the job of playground designers a lot harder. This is the reason why the playgrounds that you see everywhere all look more or less the same. A majority of playgrounds are “post and deck” systems with standard swings, slides, and monkey bars in one piece of equipment."