ESTABLISHING PERFORMANCE GUIDELINES FOR SPORTS FIELDS IN AUSTRALIA

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1 ESTABLISHING PERFORMANCE GUIDELINES FOR SPORTS FIELDS IN AUSTRALIA Draft document prepared by the Sports Turf Institute Nov 2011 Brief This information sheet provides recommended playing surface quality and safety performance guidelines for various levels of outdoor sport. It is not intended to be a code of practice, but instead a tool for councils wanting an objective means of planning and monitoring the management and performance of their fields What are performance guidelines? Guidelines are measurable and define limits of performance. Guidelines for sports surfaces standards can be used to describe: - How the player s body responds to the surface (e.g. traction, hardness) - How the ball (if used) interacts with the surface (e.g. rebound height, smoothness and speed of roll) and; - Other aesthetic features of the surface, such as appearance Why should councils have guidelines and look to monitor surface performance? Having measurable/objective, rather than subjective, methods of measuring surface properties provides greater clarity with regard to what is being specified. For example, terms such as hard, slippery or uneven are open to variation based on the individual s personal assessment. In contrast, putting a measurable value on, say, surface hardness overcomes operator bias and also allows benchmarking over time and between sites. How performance guidelines could be used by a council Objective information on surface performance could have a number of possible uses, including: - Providing both the surface user and provider groups with a precise means of defining the quality and safety of the end product - Providing a basis for tendering out work - Enabling auditing of contractor activity or turf manager operations - Bench marking progress over time or against another system (e.g. improvement in performance), and: - Providing a basis for negotiating a contract or resolving disputes (including injury/insurance claims).

2 In Australia insurance companies are requiring councils to implement risk management strategies to prove duty of care. Strategies to include: - Documentation of surface performance assessment - Regular maintenance of grounds to agreed to standards - Factual evidence such as photos and objective data Example: Maroondah City Council Grounds management linked to audits (by A. Dowie in Turfcraft Aust Nov/Dec 2005) Recommended performance guidelines for Australian sports fields In compiling the following recommended guidelines consideration has been given to the key properties of the playing surface that impact on performance, namely; 1. Surface gradient 2. Surface levelness 3. Drainage performance 4. Grass cover/bare ground 5. Weed content 6. Hardness 7. Stability/traction 8. Smoothness of ball roll or bounce 9. Speed of ball roll Reference has also been made to the methodology used in the national sports field best use modeling system and to previous recommended standards compiled for PLA by Neil Power and David Vial. Regard has also been given to standards recommended by international sports bodies, such as IRB and fifa.

3 Recommended performance guidelines for sports fields in Australia Component Method of test Comments Limits Surface gradient Use of topographic survey information Consider requirements of specific sports; sport fields can be too sloped; slope can aid drainage Maximum gradient in any direction of 1:70 for most sports and levels of sport; Up to 1 in 50 could be used for lower grade Surface evenness (mm) Use of 3m straight edge and/or 5m string line Surface unevenness impacts on both player safety and smoothness of ball roll/bounce <100 mm variation under a 5m string line <20mm over 3 m straight edge (Premier/first grade) level <30mm over 3 m straight edge (lower club standard) Smoothness/Trip index Use of 1 m straight edge and ruler Related to the micro-levels, as they affect surface footing or trueness of ball bounce/roll No tufty grass plants >15mm above turf canopy No divots deeper than 20mm Ground cover assessment Use of a 0.25 sqm quadrate Relates to surface appearance, stability and uniformity; bare spots can become low spots Minimising bare areas also allows faster grass recovery from wear and limits opportunity for weeds to come in. In the high wear areas of the ground total turf cover to be > 98% start of season; >than 85% mid-season (end May) No bare patches > than 200mm diameter start of season; < 10 bare areas >200 mm diameter per field mid-season Weed content (%) assessment using a quadrate 1 Impacts on surface appearance and surface uniformity For premier grounds < 10% grass weeds; <2% broad leaf weeds For community/club level grounds < 20% grass weeds; <5% broad leaf weeds

4 Rooting depth(mm) observation after core sampling Relates to ability of turf to withstand stress and the frequency of watering Effective rooting depth greater than 125mm Sward height (mm) Use of a floating disk Grass height relates to performance in relation to ball bounce and roll, as well as impacting on surface hardness and traction. Sward height will be sport and species/cultivar specific. Hockey - 8mm to 20mm Cricket (excluding wicket) - 10mm to 35mm Soccer - 20mm to 40mm AFL - 20mm to 50mm Rugby Union / League - 40mm to 55mm Surface hardness (g) 2.25 kg Clegg Hammer for player/surface interaction An important safety index measure. Hardness relates to injury potential after impact with the ground Gmax readings above 150 indicate cause for concern, the absolute upper limit is 200 Gmax Clegg hammer readings should fall between 50 to 120 g (3 rd drop) Above 150 is considered at high risk Soil condition Going stick Hardness relates to the soil moisture content, level of compaction and in turn resistance to root penetration. Going stick index value of between Traction (Nm) Use of studded disk apparatus Relates to surface stability and risk injury to players due to insufficient or excessive traction. Low traction also relates to surface damage due to divotting. Test values to fall between Nm

5 Soil drainage status Duration of ponding after heavy (more than 50mm in 48 hours) rain; Presence of mottles or gleying in surface 100mm Drainage performance is critical for minimising ground closures and for minimising damage to turf 1 st class grounds Surface is not squelchy 1 hour after rainfall ceases Club level grounds Surface is not squelchy after 6 hours General sports field Surface is not squelchy after 24 hours Infiltration rate (mm/hr) Use of ring infiltrometer Critical for efficient irrigation and absorption of rain and also for good drainage > 100 mm/hr for 1 st class use grounds > 50 mm/hr for club level grounds > 25 mm/hr for general purpose grounds Earthworm surface casts Count number of surface cast in a quadrate Only likely to be a major consideration for sand carpet grounds in temporate regions < 10 surface casts per m 2