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Figure 5. Durability – Felt wearing device for test method ITF TB 05/01.
All dimensions are given in centimetres.
Size (Durability) – Test Method ITF TB 06/01: A drop gauge measuring in
centimetres to at least three decimal places, to a capacity of 10 cm. The contact foot of
the drop gauge shall be a circular metal disc of diameter 1.2 ± 0.1 cm.
1.4 Test Procedure
From the 72 balls submitted for approval (36 balls for Stage 2 and Stage 3), the ITF
randomly selects 24 for testing (12 balls for Stage 2 and Stage 3). The ball containers
are opened and the balls are then stored on racks in the Controlled Environment for a
minimum of 24 hours prior to testing. Each ball should be individually marked
(preferably with a permanent marker) so that test results can be assigned to a
particular ball.
Following visual inspection, the test procedure should be carried out on each ball in
the following sequence:
i. Pre-compression. Apply to each of the three axes in succession, as described in
Section 1.3. All subsequent tests are to be completed within two hours of pre-
compression.
