ITF

41 Classification Surfaces are categorised as follows: Category CPR Slow 29 Medium-slow 30-34 Medium 35-39 Medium-fast 40-44 Fast 45 Table 2. Court Pace Rating categories. As a guide, the tolerance in the mean CPR value for a court installed by experienced contractors using quality materials and conventional methods at a reasonable cost is ± 5 CPR points from the quoted value. This tolerance applies to a new court as/unless specified by the end-user. The variation in CPR between the test location means, excluding the court markings should not exceed 10 CPR points. Note: CPR may vary depending on the nature of the materials that support the uppermost playing surface of a court. The coefficients of friction and restitution of a surface are categorised as follows: Category COR COF High 0.85 0.71 Medium 0.79-0.84 0.56-0.70 Low 0.78 0.55 Table 3. Coefficient of restitution and friction categories. Surfaces with a COR of less than 0.70 are not recommended for use as tennis courts. The maximum variation 1 in COR between the test location means, excluding the court markings, should be ≤ 0.05. The maximum variation in COF between the test location means, excluding the court markings, should be ≤ 0.05. Figure 3 illustrates how friction (COF) and vertical restitution (COR) are combined to give CPR, using the equation on page 42. Surfaces are typically perceived to play 'faster' as CPR increases, which can result from a decrease in friction and/ or restitution. 1 Variation is expressed as a standard error, i.e. standard deviation of all tests divided by the square root of the number of tests.

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