Australian Open introduces new extreme heat policy

HIGHLIGHTS: Roger Federer d. Cameron Norrie, 6-1, 6-1

The Australian Open is introducing a new heat policy called the AO Heat Stress Scale, which provides a broader assessment of weather conditions.

It measures air temperature along with humidity, reflected heat and wind conditions to provide a rating of 1 to 5. The tournament's prior Extreme Heat Policy had used a WBGT reading that took into account just air temperature and humidity.

When the HSS reaches a rating of 4, players will be allowed to take heat breaks. The referee will be allowed to suspend play when a rating of 5 is reached. During a suspension, matches in progress stopped following the next even game of the set or a tiebreak, the roof will be shut on the three stadium courts and no matches will be started on other courts.

The new rule also adds a 10-minute heat break for the men's competition between the third and fourth sets, to go along with the 10-minute break between the second and third sets in the women's competition.

The HSS rating will be visible to players, with the tournament recommending extra hydration and cooling as the index increases.

The tournament said the policy had been developed using new technology and "months of research and testing."

It comes following controversy around the extreme heat at the tournament a year ago, which had several hot days but none except the men's final produced a reading sufficient to allow a suspension. A second-round meeting between Novak Djokovic and Gael Monfils was played in 40C, with the on-court temperatures projected to be much higher, but the WBGT reading did not get to the level required for a suspension.

The tournament is also installing measuring devices at more locations.

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