Table 5. .
Example of Wet-Bulb Globe Temperature (WBGT) Guidelinesa
| WBGT Reading |
Activity Guidelines and Rest-Break Guidelines |
| Under 82.0°F (27.8°C) | Normal activities: provide ≥3 separate rest breaks/h of minimum duration 3 min each during workout. |
| 82.0–86.9°F (27.8°C–30.5°C) | Use discretion for intense or prolonged exercise. Watch at-risk players carefully. Provide ≥3 separate rest breaks/h of minimum duration 4 min each. |
| 87.0°F–89.9°F (30.5°C–32.2°C) | Maximum practice time = 2 h. For football: players restricted to helmet, shoulder pads, and shorts during practice. All protective equipment must be removed for conditioning activities. For all sports: provide ≥4 separate rest breaks/h of minimum duration 4 min each. |
| 90.0–92.0°F (32.2°C–33.3°C) | Maximum length of practice = 1 h. No protective equipment may be worn during practice and there may be no conditioning activities. There must be 20 min of rest breaks provided during the hour of practice. |
| Over 92.1°F (33.4°C) | No outdoor workouts, cancel exercise, delay practices until a cooler WBGT reading occurs. |
Guidelines for hydration and rest breaks
1. Rest time should involve both unlimited hydration intake (water or electrolyte drinks) and rest without any activity involved.
2. For football, helmets should be removed during rest time.
3. The site of the rest time should be a “cooling zone” and not in direct sunlight.
4. When the WBGT reading is greater than 86°F (30°C):
a. Ice towels and spray bottles filled with ice water should be available at the “cooling zone” to aid the cooling process.
b. Cold-immersion tubs must be available for practices for the benefit of any player showing early signs of heat illness.
Definitions
1. Practice: The period of time that a participant engages in a coach-supervised, school-approved sport or conditioning-related activity. Practices are timed from the time the players report to the field until they leave the field.
2. Walk-through: This period of time shall last no more than 1 h, is not considered to be a part of the practice-time regulation, and may not involve conditioning or weight-room activities. Players may not wear protective equipment.
Example originates from Georgia High School Athletics Association wet-bulb globe temperature guidelines and is only applicable to those who practice, condition, train, or compete under similar environmental conditions. Guidelines should be region specific and based on the following criteria: (1) environmental conditions, (2) intensity of activity, (3) heat-acclimatization status, (4) equipment and clothing, (5) fitness of individual, and (6) age of participants.