Scratching Below the Surface
How Safe Is Your Playground Surface?
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."
Bonded Surfaces: Upsides & Downsides
Bonded or synthetic surfaces, though generally more expensive, have a greater life span with a substantial reduction in maintenance requirements, said Jennifer Smith, vice president of a manufacturer specializing in poured-in-place and rubber tile surfaces, based in Baton Rouge, La. "Many of these materials include a warranty on materials and installation including safety. When installed correctly, synthetic surfaces provide enhanced safety, excellent drainage and a better deterrent against insects, sharp objects (such as glass or needles) and mold/mildew growth."
Synthetic surfaces, on average, require much less material to provide the same or better fall protection. For instance, Smith said, 6 inches of rubber mulch can provide 10 feet of fall height protection, while it would take 12 inches of wood mulch for similar protection, assuming these applications are maintained daily. A synthetic surface would require an average depth of 3.5 inches to provide 8 feet of fall protection. "Additionally," Smith said, "with synthetic surfaces, designs and colors can be introduced into the playground landscape, adding an extra layer of fun and excitement for guests."
Hollowell agrees with Smith, and added that "poured-in-place, or bound surfaces also meet all requirements set forth by the American Disabilities Act. It's permeable. People, children can safely play on the surface, even after it rains."
Poured-in-place is a good non-slip surface, even as it wears. It also provides wheelchair access and has a high enough rolling resistance to ensure that a severely challenged person will be able to navigate the playground safely.
Bound surfaces like PIP are very low maintenance. This is why school districts and city and recreation officials often prefer it. Maintenance personnel can sweep or blow off leaves every few days as required. "Our industry recommends that the owner reseal the surface every two to three years, depending on the usage. It's a very inexpensive process," Hollowell said.
The downsides to these types of surfaces is that they have more upfront material and installation costs, require professional installation, can be extremely hot during summer months and generally do not have the same impact resiliency as loose-fill products, observed Mrakovich. "I would also suggest getting your unitary surface impact-tested periodically, every three years or so. The reason? Because unlike loose-fill surfaces where you can measure the thickness of your surfacing to see how much you need to top off periodically to keep it at safe levels, you can't see what's going on down below the top wear layer of a unitary surface."
The surface may look good on the top, he said, but if it has begun to decay or is getting harder beneath the wear layer, it might not be safe, and the only way to determine that is to perform a drop test. There are many playground consulting companies that offer this.
Another bonded surface option consists of tiles. Brennan Prins, director, of a Petrolia, Ontario-based company that produces rubber surface tiles, said that "when it comes to playground surfaces, it's all about beginning with the end in mind."
His company's rubberized tiles offer great fall protection, and are cost-efficient and durable, made to last 25 to 30 years. "We have zero maintenance required with our tiles. That does not mean it won't get dirty and won't need cleaning. Poured-in-place surfaces must be maintained or they will fail compliance tests, because it slowly becomes clogged with dirt and debris. Poured-in-place achieves fall safety, but performance gets worse. Rubber tile surfaces, if well-built, can last a long time."
Talk About It
When you need a new playground safety surface, you need to know what to ask potential partners and manufacturers. Your first priority must be safety and accessibility.
This could change depending on the location and age group, said Smith. "However, the surface you choose must be IPEMA Certified to provide fall protection according to American Society for Testing and Materials (ASTM) 1292 and it must be ADA accessible as per AS™ F1951."
Other considerations should include proper drainage, low maintenance, life span and cost, she said. "Choosing a company to provide your safety surface can make all the difference in the safety and long-term performance of your playground surface. Look for a company that has experience and longevity in the industry. A good company will step you through the process and help you select the best surface for your facility and not just the surface they can provide. A good company will be transparent and provide you with information regarding past projects similar to yours. They will provide references for you to call or visit so you can see similar applications first hand (old and new). A good company will stand behind their work and provide you with support before, during and after the installation."
Begin, Mrakovich said, by asking the manufacturer for recent impact test results per American Society for Testing and Materials (ASTM) 1292, within a few years, and if they have any test results from an actual installation out in the field. Are the numbers on the edge of failing? If using EWF, ask for test results for AS™ F2075, or for loose fill rubber, ask for AS™ F3012, which checks for sieve analysis, tramp metals like nails and staples and hazardous metals like lead, mercury and arsenic.
Get a recent AS™ F1951 test result showing it passes for accessibility, Mrakovich said, "but also see if the vendor has any installation instructions or maintenance recommendations to keep their surface accessible. If you can maintain it, you can rest assured you'll meet ADA guidelines if you install it correctly per the manufacturer's instructions.
Availability is also key, Mrakovich said. Any vendor can sell you something. But will you have the support available when you need it, will the vendor be there when you need to know how to get the most out of your purchase or when there is a warranty issue?
Budget considerations are bottom-line issues everywhere these days, Mrakovich said. It's easy to say, "let's put a unitary surface in so we can lower our maintenance costs," but unitary surfaces range from $10 to $20 a square foot while a loose fill surface such as engineered wood fiber is only about $1.50 to $2.50 a square foot. For some large school districts and municipalities that have literally hundreds of playgrounds, it's easier to top-off and maintain the playground on a weekly or monthly basis, than forking out a large sum of money and draining their budget. But if you don't have the personnel to maintain a loose fill surface, maybe a unitary surface is for you."
The Weather Factor
All of the surfaces mentioned can be used in various climates, Smith said. "The biggest challenges with fluctuating climate are safety and fall protection, impact attenuation."
During the summer months, anything exposed to direct sunlight will become hot. "This is not different for playground surfaces that become very hot when exposed to direct sunlight," Smith continued. "For all playgrounds shoes are always recommended. Parents and caregivers must exercise caution before allowing a child to play on the surface or playground equipment until it has been self-examined for temperature. Is it hot to the touch?"
The best way to help reduce the temperature of surface on a playground is to include a shade structure. But placing a shade structure directly over the top of the equipment may not be enough, Smith advised. "The best results occur when the shade structure is strategically located or angled to block sun exposure according to the direction of the sun during the hottest time of the day. Another consideration is how close the playground is to a glass, mirrored or metal building that may be reflecting on to the surface early in the morning or later in the evening."
Meanwhile, during the winter months when the temperatures fall below freezing, the impact attenuation performance of the safety surface can be compromised. "In this case," Smith said, "it is recommended to discontinue use until the surface is no longer frozen. For this situation, a surface that is porous and includes excellent drainage is ideal."
When you need a new playground safety surface, your first priority must be safety and accessibility.
You wouldn't necessarily think that drainage would lend to a surface's safety, but it does, Mrakovich added, agreeing with Smith. "Imagine a surface that doesn't drain well in a cold climate where temperatures fluctuate, causing snow to melt and then re-freeze overnight. Any amount of frozen moisture that is within the surface makes the surface less resilient and unable to provide good impact attenuation, so eliminating water from the surface will minimize this and help the surface to last longer, too. It really goes back to making sure the owner/operator of the playground has the surface installed properly and that the testing they receive simulates in the lab what the actual surfacing is going to be out in the field. When you look at the test results, look at the description of the surface to make sure it represents what you are purchasing from the vendor.
Mrakovich recommends limited play in harsh temperatures no matter where you live. "Better to be safe than sorry," he said.