Anyone who has ever been involved in the process of purchasing playground safety surfacing has probably been barraged with a host technical jargon related to safety performance and compliance issues. Technical terms such as G-max and Head Injury Criteria (or HIC) can be difficult to interpret and can make the purchasing process confusing. What do the safety standards mean? How do we interpret the data? And most importantly how do we ensure that we make the right surfacing decision for our playground?
Attempting to wade through the safety standards can be daunting, but a decision to purchase playground surfacing is not without risk, and proceeding in the absence of a basic understanding of the standards should be done with an abundance of caution.
Fortunately, and with a little guidance, the knowledge needed to make a sound purchasing decision is only a short read away!
ASTM F1292 is the safety standard designed for playground surfacing. The safety performance of protective surfacing is determined by using a test device very similar in function to a crash test dummy. This "crash test dummy" of sorts, provides two key measurements when impacted from various heights onto the playground surface. G-max measures the initial impact force (G's) of a child falling onto the protective surfacing, whereas HIC, or Head Injury Criteria measures the estimated severity of the impact by incorporating other variables associated with the impact.
So what does the testing really mean?
ASTM F1292 is designed of course, to reduce injury, but the types of injuries that it was designed to reduce are limited to life threatening and debilitating injuries. Consider that a blow to the head from a professional boxer registers at approximately 52 G's or that a car crash at 25 mph would result in an impact force of approximately 125 G's. The overwhelming amount of recent research into football concussions has shown brain injuries occurring at impacts as low as 60 G's. Now consider that the passing grade for playground surfacing is currently set at 200 G's.
Correlating 200 G's with the above examples can certainly provide some much needed perspective when determining the level of safety performance that's acceptable for your playground.
Another often over looked aspect of the standard revolves around the pass/fail numbers of 200 Gmax and 1000 HIC. Often decision makers assume that as long as the surface performs under the specified values, it is compliant. While this is technically true, most fail to consider that these values are maximum thresholds that cannot be exceeded at any time throughout the entire life cycle of the protective surfacing. Further, many fail to consider the dynamic nature of playground surfacing. Playground surfacing can represent a big investment. Understanding that it's performance characteristics will deteriorate over time provides strong incentive to set initial safety performance ratings as low as possible, and with long-term compliance in mind.
Although many factors go into what type of surface constitutes the best option for particular application, the primary function of any protective surface is the provision of long-term fall protection. As decision makers become more attuned with safety standards, leading manufactures have responded by introducing new and innovative products. These products are designed to exceed current safety standards by significant margins with the goal of providing a long-term solution to safety.
Regardless of the type of surfacing you are considering, there are manufacturers currently designing and installing systems with initial safety values set as low as half the maximum threshold. The options for playground surfacing are broad, ranging from lower cost loose fill options such as rubber mulch, to more complex and costly systems including vulcanized interlocking tiles, and poured-in-place/loose fill hybrid systems. Each of these systems offers advantages unique to different needs and applications. Regardless of the type of surfacing chosen, sophisticated purchasers all understand that the decision to select a playground safety surface should always be rooted in the common objective of providing high performance safety ratings backed by extensive product warranties.