ITF

38 For all tests, balls should be kept pressurised in their cans at 23 ± 2°C prior to testing, and pre-compressed before use. Pre-compression is intended to remove temporary 'set' in the ball, which may occur during prolonged storage. Pre-compression consists of compressing the ball by approximately 2.5 cm on each of three diameters at right angles to one another in succession; this routine is carried out three times (nine compressions in all) 1 . Balls should not be subjected to more than 12 impacts each, excluding any pre- compression impacts, to ensure that their original properties are retained throughout testing. Average ball temperature should be recorded to the nearest degree Celsius for each test location/sample. An infrared thermometer, calibrated to ± 1°C, is recommended for this purpose. Test reports Each test performed requires a report to document the results and conditions. The test report should contain all relevant information, including: Reference to the ITF test method and code. Identification, and detailed description, of the surface composition, including supporting layers, and its condition. Information on the test environment: temperature; humidity; atmospheric pressure; altitude; venue. Statement of the ball brand name and country of manufacture. All results. Overall result, typically the average and variation of the measurements (for comparison against the category or recommendation). 1 Firing the ball three times at an oblique angle onto a smooth, rigid surface using a ball projection device at 30 ± 2 m/s is an optional means of applying pre-compression.

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