New England Blade – Arthur Eddy, ASLA, LEED AP
A synthetic turf field can be a great asset for an athletic facility limited by space and increased pressures from the demands of multiple teams and users. For a long time, there was the perception that synthetic turf fields are maintenance free, but that ideal is the farthest from the truth. The reality is that maintenance is critical to the performance, safety, and longevity of the turf.
Synthetic turf systems are made up of synthetic turf fibers and some type of infill whether that is a crumb rubber or a natural material. Regardless of the infill material, it will move and displace within the turf fibers during use. This movement will have an impact on the safety and performance on the field including the following: GMax: Any turf system that does not include a shock pad is relying on the infill for its impact attenuation. The higher the GMax, the harder the surface; the lower the GMax, the softer the surface. ASTM F1936 requires a maximum GMax of 200 g. Currently, the NFL and FIFA require 165 g.
HIC: Head Injury Criteria measures head impact on the field. HIC is measured by critical fall height. World Rugby requires a critical fall height of >1.3m.
Rotational Resistance: Rotational resistance simulates an athlete’s ability to alter direction. The level of infill and the amount of fiber revealed will have a direct impact on how an athlete’s foot will react in the field. FIFA requires 30Nm-50Nm.
Vertical Deformations: Vertical deformation is the energy restitution that moves into an athlete’s legs through the surface. Too soft, and athletes can get fatigued and too hard, athletes will feel soreness or stiffness. FIFA requires deformation that is between 4mm-10mm. Any of the above safety testing is impacted by changes in the turf system and more importantly changes in infill depths. Being charged with maintaining a synthetic turf field, it is critical that infill is being checked on a regular basis and that attention is given to high use areas, i.e. soccer penalty kick dots, corner kicks, lacrosse mounts, center field dot, and high use practice areas, etc. Adding infill when necessary will help to keep the surface safe, performing, and add longevity by deferring costly replacement. Simply grooming the field may not be enough.
In a year of a synthetic turf field, your high use areas are changing based on seasonal sports. Adapting to the changes will help to focus maintenance efforts. Unlike a natural grass field, without further investigation you are not going to see the areas that need attention without the appropriate infill depth equipment. Lastly, it is important to understand the frequency with which you need to attend to your field. Each manufacturer has guidelines as to how often you should be maintaining your field to ensure that you are meeting your manufacturer’s warranty and log all the work completed.
A synthetic turf surface can be a valuable asset that can have a wide range of benefits providing safe, performing facilities and proper maintenance goes hand and hand with the users’ enjoyment.
This article is based on a NESTMA webinar presented in January by Art Eddy, ASLA LEED AP. Art is CEO of RePlay Maintenance in East Greenwich, Rhode Island. Connect with Art via email at firstname.lastname@example.org, or phone (877) 641-1819.READ THE ISSUE