| Heat Category | WBGT Index (F) | Activity Guidelines |
|---|---|---|
| No Flag | Under 80 | Unlimited activity with primary cautions for new or unconditioned athletes or extreme exertion; schedule mandatory rest/water breaks. (5 min rest/water break every 30 min) |
| Low (Green Flag) | 80-84.9 | Normal practice for athletes; closely monitor new or unconditioned athletes and all athletes during extreme exertion. Schedule mandatory rest/water breaks. (5 min water/rest break every 25 min) |
| Moderate (Yellow Flag) | 85-87.9 | New or unconditioned athletes should have reduced intensity practice and modifications in clothing. Well-conditioned athletes should have more frequent rest breaks and hydration as well as cautious monitoring for symptoms of heat illness. Schedule frequent mandatory rest/water breaks. (5 min rest/water break every 20 min) Have cold or ice immersion pool on site for practice. |
| High (Red Flag) | 88-89.9 | All athletes must be under constant observation and supervision. Remove pads and equipment. Schedule frequent mandatory rest/water breaks. (5 min rest/water break every 15 min) Have cold or ice immersion pool on site for practice. |
| Extreme (Black Flag) | Over 90 | SUSPEND PRACTICE |
Source: North Carolina High School Athletics Association
| Heat Category | WBGT Index (F) | Easy Work
|
Moderate Work
|
Hard Work
|
|||
|---|---|---|---|---|---|---|---|
| Work/Rest (min) | Water Intake (qt/hr) | Work/Rest (min) | Water Intake (qt/hr) | Work/Rest (min) | Water Intake (qt/hr) | ||
| 1 | Under 82 | NL | 1/2 | NL | 3/4 | 40/20 min | 3/4 |
| 2 (green) | 82-84.9 | NL | 1/2 | 50/10 min | 3/4 | 30/30 | 1 |
| 3 (yellow) | 85-87.9 | NL | 3/4 | 20/40 min | 3/4 | 30/30 | 1 |
| 4 (red) | 88-89.9 | NL | 3/4 | 30/30 min | 3/4 | 20/40 min | 1 |
| 5 (black) | Over 90 | 50/10 min | 1 | 20/40 min | 1 | 10/50 min | 1 |
Source: U.S. Army Public Health Command