We're always uncertain how to respond to these kinds of concerns. It's sort of like trying to discuss safety issues about a walk in the woods, so let me just share some things with you.
For months, we've been looking for safety information with regard to natural play areas and have found nothing. They seem to fall somewhere between playgrounds, parks, and gardens, so I think the insurance industry hasn't quite figured out how to develop safety standards on which they base their risk assessment.
Sometimes we cavalierly suggest that natural play areas are really nothing more than landscaping, and as far as we know, insurance companies don't yet have an opinion about the safety of landscaping, or how to assess the risks inherent in landscaping.
So let's take one thing at a time.
The majority of serious playground accidents result from falls off high play structures. That's why there's so much attention paid to fall/use zone material and depth (see statistics at the end of this article).
Our designs steer away from free-standing, high things for that very reason. We provide height with natural berms, and sometimes with piles of rocks, but in the case of rocks, for instance, just in the event a child slips and falls, we do put wood chips around the base. But if there is a fall directly to the ground. it's always going to be from the lowest level of rock, so the fall would be pretty short, and therefore injury minimal, if any.
We recently designed a play area for an elementary school, and they wanted a fitness course with climbing things, so we have an 8' climbing wall, and 8' peg climbs. But in those cases, we've followed the ASTM and CPSC guidelines for the size and depth of the fall zone, so should there be any falls, we've met the current safety standards. If there is a similar situation in any of the play/learning elements we include in our designs, we'd meet it the same way.
What we really come down to with natural playgrounds, is whether kids are safe running on the grass, or on the stone dust walkway, or whether they're safe jumping in a pile of leaves, or walking along the top of a low stone wall, or sitting under the trees, or playing in the ground-level fort, or on the ground-level labyrinth. Given their surroundings, and the grass or soil underneath, I should think they'd all be safer in here than on a manufactured playground or on the streets of their neighborhoods.
If a child gets hurt stumbling and falling on a rock, I'm not sure that's any different from a child stumbling and falling on the sidewalk outside their home. Such kinds of accidents do happen, and unless you want to keep the child in their classroom or house all day, that may just have to be the level of risk that's tolerated. I think it would be hard to prove negligence in the event of such an accident.
Incidentally, the only request this school's insurance agent made was that instead of calling it a "challenge course," we should call it a "fitness course" which his company had no trouble covering. The rest of the natural play design apparently fell within their guidelines...
Other kinds of risks on a natural playground might include vandals putting shards of glass in the sandbox or garden soil, or putting sharp objects in a pile of jumping leaves, but those kinds of things could also occur on a manufactured playground, so they will be on your daily checklist for play area safety anyway, and should be able to be avoided.
There is another approach, and that is to look at some of the safety issues surrounding standard playground equipment. These all fall outside the risks of Natural Playground components.
Take a look, for instance, at the following two paragraphs:
A child's fall in a playground in Chicago in 1985 ended up with most pieces of equipment being removed from Chicago's parks. A two year old fell from the top of a slide and suffered brain damage. His family sued the manufacturer of the slide, the contractor who installed it and the Parks Board. A settlement was reached for $1.5 million. The insurance coverage was canceled but eventually renewed for much less coverage at a greatly increased price. "Playgrounds are a terrible risk for any carrier to have to assume," says the manager of the insurance company.
Recent vandalism in Winnipeg saw that a vandal had removed all bolts from a major piece of playground equipment. The discovery was made just prior to recess when many young children would have probably climbed onto the structure and the collapse of the equipment could have injured many children. Fire damaged equipment, graffiti and broken glass are discovered on a weekly basis in many (manufactured) playgrounds. For these reasons and for normal replacement of worn equipment, it is strongly recommended that a weekly, detailed inspection be carried out.
Again, I think the element of risk and potential accidents is far higher from manufactured equipment than it is from natural play components, but there have been no studies as far as I know. Certainly, one's instincts would favor natural play areas for all the reasons mentioned above.
One last, rather interesting view, would be to review the articles on playground boredom (see our site), which conclude that kids get easily bored on manufactured equipment, and because of that, they take more risks on it, and tend to be more aggressive around it, and therefore are subject to more accidents because of this behavior. We've certainly seen this on our playground visits, and many children tell us that they're bored with equipment and why, and that they favor natural play experiences because they offer so many more engaging options.
It might be interesting to get a response from your insurance agent, the only problem being that if they're pushed to make a decision, and have no guidelines, they may develop them on the spot without any clue whatsoever. If you decide to pursue this, perhaps you should educate the agent first, take him/her out for lunch, or whatever, to warm them up and get them receptive to something new!
Take a look at these statistics - all of which have to do with manufactured, equipment-based playgrounds. Keep in mind that there are no such statistics for Natural Playgrounds. One reason might be that Natural Playgrounds have far fewer play elements that pose a risk for injury. And interestingly enough, Natural Playgrounds have much more play and learning value, and are far less costly, so common sense suggests that they might be worth considering!
Some interesting numbers
Statistics courtesy of the National Program for Playground Safety:
In 2006, the American Academy of Orthopaedic Surgeons reported that almost half a million playground injuries occurred among people younger than 20. More than 177,000 injuries came from monkey bars or other climbing equipment, nearly 128,000 from swings, more than 113,000 from slides and almost 67,000 from other playground equipment.
The estimated cost for playground equipment-related injuries for this age group?
$12.8 billion in medical, legal and liability, pain and suffering, and work-loss expenses.