Monday, April 16, 2012

The Value of Shade on the Playground

The Consumer Products Safety Commission in their publication "Handbook for Playground Safety"  (publication 325) cites a reference to the American Academy of Dermatology research indicating that one in five Americans will develop skin cancer during their lifetime.  Sunburn, heated bare metal, hot platforms, hot steps and ground surfacing heated enough to burn children are all referenced concerns.   Sun exposure is one of the major risk factors for melanoma, others forms of cancer and early aging of the skin.  Sunlight, whether direct of reflected contains ultraviolet rays, known as UVA and UVB.  UVA rays damage the skin by drying and creating wrinkles.  UVB rays are the cancer causing type, and damage can last a lifetime.   This isn't an issue only referring to sun bathing or tanning salon visits.   Sun exposure during early childhood may account for up to 80% of our lifetime totals.   The UVA and UVB rays seem to take most of the publicity and blame.  Sunscreens are recommended with high SPF ratings when our children are outdoors.   Perhaps UV rays aren't the only risk.

One line in the CPSC recommendations stands out as somewhat odd, if not impossible.  While conducting a playground inspection for a client, I stopped on the entry referring to a slide being oriented so it is out of direct sunlight.   I was a bit confused by the thought of trying to somehow rotate the structure I was looking at so that the slide wouldn't be in direct sunlight.  In my longitude and latitude, direct or indirect sunlight is going to strike that slide from sunrise to sunset.     I have now started paying attention to exactly how hot things are on the playground.   

Using an infrared laser thermometer I obtained a temperature from every surface I could think of during a playground inspection.  The results are nothing less than shocking:

Ambient Temperature   96F (as a reference point, the thermometer on the wall outside this building would say it was this temperature outside)

Concrete Sidewalk enroute to playground 102F

Blue ramp into playground         (in sun)               125F

                                                         (in shade)           90.8F

Black border timber perimeter  (in sun)               130F

                                                         (in shade)           99.9F

Engineered Wood Surfacing       (in sun)               128.3F

                                                         (in shade)           87.7F

Coated metal deck                        (in sun)              105F,111.5F

                                                         (in shade)           91F,92.4F

PVC Roto-Molded Slide               (in sun)                100.8F

                                                         (in shade)           86F

PowderCoated Steel Post            (in sun)               93.9F

                                                          (in shade)          89.3F

Metal Climber                                (in sun)               90.4F                    

I remember learning to dip my wrist or elbow into the bath water to ensure the water temperature wasn't too hot, around 100F or less.  I learned to set my hot water heater to 110F to prevent scalds.  Some of the temperatures above are far higher than what would be expected to cause a first degree burn.   Children have thinner skin than adults and will react to these temperatures more quickly or more severely than to the adults supervising the children at play on the playground.     I was able to find a reference ( that states a 3rd degree burn can occur from hot water at 140F in 15 seconds.   With the temperature reading on the wood surfacing under the playground at 128F, the very material meant to protect lives may be causing a risk.    More than 15 seconds on the playground seems like a somewhat regular occurrence.  While the burn statistics I can find seem to be water related, 20 minutes on a playground with temperature readings this high seems to be somewhat more than only a risk to our children. 
I will continue to look for a way to orient a slide out of direct sunlight.  In the meanwhile, I think we need a shade cover over the playground!