Standards for the Playing Quality of Artificial Turf for Association Football

Abstract

In Britain, over 100 full-sized artificial playing surfaces have been installed for association football (soccer). Performance standards for the playing quality of artificial turf pitches (athletic fields) are required, and the development of different test methods is reviewed. For surfaces for soccer, it is necessary to consider both ball/surface and player/surface interaction. The principal techniques for testing surfaces used in Britain are ball rebound resilience, rolling resistance, traction/friction, sliding resistance, surface hardness (using Stuttgart and Berlin Artificial Athlete instrumentation), and the impact characteristics of a 5.5-kg head striking the turf. Playing quality standards for soccer on artificial turf surfaces published in 1985 gave performance requirements for three levels of play. Classification to a national standard required ball rebound resilience in the range of 25 to 46%, ball deceleration of 0.45 to 1.5 m/s2, and a traction coefficient of 1.5 to 2.2. These limits are compared with data obtained from six natural turf pitches used by professional clubs covering a wide range of weather and pitch conditions. For ball rebound resilience and traction there was a reasonable comparability of the specified performance limits and the data for natural turf: the interquartile ranges were 31.7 to 44.4% for ball rebound resilience and 1.38 to 1.96 for traction. Some slight modifications to these performance limits are, however, proposed. For natural turf pitches, almost 90% of deceleration values were in the range 0.45 to 1.5 m/s2, but it was evident that values on artificial pitches, after the pile had been compacted by play, were not satisfying the threshold of 0.45 m/s2. Peak deceleration of a 5.5 kg headform after it had been dropped from 1.5 m was lower on natural turf surfaces than on artificial pitches. However, the values on the artificial pitches were comparable with those of safety tiles used as a playground surfacing.