The safe height of a deck will depend on what type of surfacing you will be using below your structure. Engineered wood fiber is one of the best options with the highest critical fall height. Your playground representative or dealer will be able to speak more directly to local codes and standards as well. My recommendation would be to look for vendors that have both CPSC and ASTM certified equipment - as their equipment will be compliant and is held to the highest safety standards. You can take a look at these vendors for an idea of which companies are ASTM and CPSC certified: kaboom.org/vendors

Are you building a playground? I would also recommend you check out the completely free KaBOOM! DIY Project Planner online tools and resources. You can create a project page and get started by clicking here (you'll have to create a log in first): projects.kaboom.org/projects/new

Can someone point me to a resource for determining unsafe playground equipment heights (for an elementary school)? I've found a NYPIRG citation that says over six feet is unsafe, but I cannot find a height listed anywhere else. I'm specifically concerned about a ten-foot-high platform from which kids access two slides and an interior climbing ladder. Thank you!