Operating standards for heat illness prevention at tournaments, based on the WBGT heat index.
At tournaments organized or co-hosted by Pickleball Japan (PJ), we’ve set operating standards for heat illness prevention based on the Wet-Bulb Globe Temperature (WBGT) index published by Japan’s Ministry of the Environment, so that players, staff, and spectators can all enjoy pickleball safely. On tournament day, decisions such as scheduling breaks or pausing play are made according to the standards below.
Tournaments are run according to the following standards, based on the WBGT value published by the Ministry of the Environment.
| WBGT | Guidance Level | Action Taken |
|---|---|---|
| 21–25°C | Caution | Players are actively encouraged to hydrate and replenish salt. |
| 25–28°C | Warning | Risk of heat illness is elevated; players are actively encouraged to rest. |
| 28–30.1°C | Severe Warning | In addition to frequent breaks, cooling measures such as ice and cooling towels are used. |
| 30.1°C+ | Special Measures | Depending on the match format, a 10-minute break may be taken before the final game. |
| 32.2°C+ | Suspension Under Review | Consideration of a Suspension of Play begins. |
When no doctor or trainer is present at a tournament, a referee will call a mandatory retirement, for the player’s safety, if the total score for the symptoms below reaches 3 points or more.
| Symptom (Suggestive of Heat Illness) | Severity | Points |
|---|---|---|
| Dizziness, brief fainting (quick recovery), partial muscle stiffness (not relieved by stretching) | Grade I | 1 point |
| Discomfort, nausea, vomiting, headache, or exhaustion (loss of strength, unable to explain the situation) | Grade II | 2 points |
| Impaired consciousness (unable to talk), whole-body convulsions, impaired limb movement (unable to walk unassisted) | Grade III | 3 points |
* If you notice any of the above symptoms, please don’t push through — notify tournament headquarters or staff right away.
During the tournament, players are encouraged to check their own hydration using the urine color chart (“Pee Chart”) below.
Aim to stay in the lighter range of 1–3. If your color is closer to 5 or higher, dehydration is likely, so hydrate and replenish salt frequently.
Additional Information
Please also see the Ministry of Health, Labour and Welfare’s dedicated page on preventing and treating heat illness.
Ministry of Health, Labour and Welfare: “Preventive Actions Against Heat Illness” (Japanese)
Pickleball Japan