This is the 3rd in a series of posts focusing with the requirements of key standards for indoor sports flooring. Globally Area Deflection is the most controversial property of sport surfaces. That is the very reason why the EU decided not to include it in their indoor multi-use sport standard (EN 14904). Area deflection does not apply to point elastic (synthetic) playing surfaces. Within North America it primarily applies to wood playing surfaces, but may be used to describe a combination (wood/synthetic) system.
Area deflection is a measurement of how well the sport surface transmits vibrations generated from an impact through the surface. A higher value for area deflection means vibrations are transmitted stronger and further within the system. If you have ever dribbled a basketball and felt the floor vibrate beneath your feet, that essentially is what area deflection measures. Lower values means the vibrations are smaller and you don’t feel them as much. Higher values often feel uncomfortable to the athlete. While ASET does not consider it a safety standard, it does correlate to the preferences of basketball players with regard to vibration levels.
As owners and architects consider this property and how it will be used in their specifications, ASET urges them to consider the following:
- If we look at DIN 18032-2 (2001) and MFMA-PUR there are exactly 2 ways to fail force reduction, 2 ways to fail ball rebound. MFMA-PUR has 2 ways to fail vertical deformation while DIN has only 1. There are 5 ways to fail area deflection at every point. Effectively area deflection is more important than the other 3 properties combined.
- A 2% difference in area deflection represents as little as 0.046 mm, or 0.0018 inches. A human hair is between 0.0006 and 0.007 inches. Even a 5% difference represents only 0.004 inches. Systems routinely fail due to 1% difference.
- Can installation methods, system materials, and job-site conditions be controlled well enough that an actual installation can deliver the area deflection levels that were measured in the lab
