3.8 Discus and Hammer Circles (Technical Rules 188–189)

Discus: Internal diameter 2.500 m ± 5 mm. Throwing sector 34.92°.; Hammer: Internal diameter 2.135 m ± 5 mm. Throwing sector 34.92°. A protective cage must surround the throwing area to protect officials, athletes, and spectators (Technical Rule 189.3). The cage must be capable of stopping a 7.26...

Source: Rule 189.3

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