Tennis heat rules change with the tournament, and that is indefensible

Four majors, four different thresholds, four different discretions, and a player who is protected in January and exposed in September.

Same sport. Same bodies. Four sets of numbers.

Each of the major tournaments operates its own extreme heat policy, with its own trigger, its own scale, and its own view about who decides. One uses a purpose-built stress scale with staged responses. Another allows a break between certain sets above a threshold. Another applies a policy to women's matches and a different one to men's, a distinction that survived far longer than it should have on the reasoning that a five set match is a different animal, which it is, in the direction of needing more protection rather than less.

The tours have their own rules again, and the referee at any given event retains discretion, so a player can be granted a ten minute break in one city and told to continue in another under conditions that measure the same. That is not a disagreement about science. There is broad agreement about what combined heat and humidity does to a working body. It is a disagreement about scheduling authority, and the party who wins it is usually the one holding the broadcast slot.

The discretionary element is where I would push hardest. A rule that says the referee may suspend play invites a judgement about a match already in progress, on a court with tickets sold and a slot to fill, and every incentive in that moment points toward one more set. Make it automatic. Publish the reading. Let the meter decide and let nobody be blamed.

The roof problem deserves a mention too, because it is the strangest inconsistency in the sport. Closing a roof changes the playing conditions substantially and it is generally done for rain rather than heat, which means a court with a roof and a court without it can be running two different tournaments on the same afternoon, and the players on the open court are the ones being cooked.

Uniformity would cost the majors something. They like their local character and they own their events. Fine. Keep the traditions, keep the surfaces, keep the scoring quirks. Agree one number for when it is too hot to play, because that is the one rule where the difference between venues is measured in hospital admissions.