Scratching Below the Surface
How Safe Is Your Playground Surface?
By Rick Dandes
Choosing the right playground surface to install—one that provides continuous, dependable protection from serious injuries in the event of a fall—is one of the most important decisions a school board administrator or recreational facility owner has to make. After all, according to the Consumer Product Safety Commission, an estimated 70 percent of all injuries on a playground are due to falls to the playground surface.
"But, let's be honest here," said Jeff Mrakovich, a research and development, certification and services manager with a Middletown, Pa.-based manufacturer. "There is no perfect surface. A surface should be the total package—safe, accessible, available and affordable."
There are basically two categories of playground surfacing: loose fill, and unitary or bonded surfaces. For the most part, loose-fill surfaces, such as engineered wood fiber (EWF), gravel, wood chips and sand, come from natural elements, the exception being loose fill rubber. These surfaces are what you might imagine them to be, loose. "In other words," Mrakovich said, "there are no binders or other chemicals holding them in place and they are generally installed in thicknesses anywhere from 6 inches to 12 inches deep, depending on the amount of fall height needed on a particular playground."
An alternative to loose-fill is bonded surface material, said Jim Dobmeier, president and founder of a Cheektowaga, N.Y.-based manufacturer of playground safety and other recreation and sport surfaces. Bonded surfaces, he said, mean the materials that make up the surface are bound, or rolled together into a monolithic surface. The most common bonded surfaces, he explained, are poured-in-place, turf top and tiles.
A poured-in-place surface, Dobmeier continued, "is mixed and applied on site by installation crews. Their makeup can come from recycled tires, virgin rubber, nylon and polyethylene, among other synthetic components. A bound surface is typically a two-layered system. There is black rubber that serves as the cushion layer and ranges in thickness from 1 to 4 inches. That is capped with a top surface, which is a nominal half-inch thickness." All of this can be created in a single color, color combination, or patterns of colors with signs and logos.
Turf tops are almost carpet-like, and come with a cushion layer identical to poured-in-place—rubber to absorb shock. It's done in different thicknesses, and instead of being covered with a colored rubber it is covered with a synthetic turf, usually green, giving the surface a natural look.
A third bound surface option is tiles, Dobmeier noted. "I liken them to be almost like making a waffle. You pour the mix through a mold, close the mold at the factory, and the tile solidifies. Then the tiles are stacked up on palettes shipped to playgrounds and laid down by installers. They have a tile look, instead of a seamless look like poured-in-place."
Loose Fill: Upsides & Downsides
These surfaces generally cost less, do not require professional installation, drain well and, on average, give greater fall height protection than unitary surfaces.
"The drawback," Mrakovich noted, is more maintenance is needed since loose surfaces are by definition, loose. "So they tend to scatter in high-use areas and need to be replenished, raked, leveled and compacted periodically in order to keep them safe and accessible, which increases maintenance costs."
You could literally spend hours a day raking loose fill to keep it at the adequate depth, Dobmeier added. "What is the cost to do that? Well, it depends on how much you pay your people and how much they are really doing it. Every few months they should be bringing in more fill because the material migrates on people's shoes and to the perimeter of the playground."
There are products to help with scattered material in high-use areas. These are referred to as wear mats and come in all sorts of sizes depending on the area that the mats need to protect. "These are not an end-all to the maintenance needed," Mrakovich suggested, "but can really reduce the amount of time spent filling in these areas on a routine basis and will help keep the area safe between maintenance intervals."
Some manufacturers, Mrakovich said, have their mats certified to certain fall heights. "Ask for test results so you aren't actually reducing the safety of these areas by installing mats," he advised. "The mats are also not intended to be installed and then left alone." The maintenance worker should still inspect them periodically to make sure the transition from the mat to the surrounding surfacing is relatively smooth, to within a half inch, which is required by ADA Standards for Accessible Design.
"I also recommend placing mats in not only obvious spots like slide exits and under swings," Mrakovich said. "Look around at your playground, and you will notice that placing them at ground-level components like play panels and transition platforms will help those with disabilities enjoy these areas without the risk of uneven surfaces."
Some playgrounds will consider sand as a surface. Sand has great play value, kids love it. But the downside is that it doesn't meet any ADA requirements, and it is not navigable for challenged people. Sand also does not meet Head Injury Criteria (HIC) above a 4 foot fall, said Mark Hollowell, sales manager of a Corona, Calif., surface material manufacturer. "Kids bring it back into the school or daycare in their shoes. This destroys the vinyl flooring prevalent in most of these facilities. There is an obvious issue with contamination. One horrible issue with all loose fill is that drug addicts hide their drug paraphernalia below grade. We have several instances of kids coming up with a needle in their leg."