Fort Detrick
Industrial Hygiene & Environmental Health Office
Heat Stress Index
Heat Stress Index is OFFLINE and will resume when hot weather arrives.
Work/Rest Cycles & Water Intake
Use heat condition information below to determine required water intake and work/rest cycles.
Heat Category |
WBGT INDEX (° F) |
Easy Work/Rest (Minutes) |
Water Intake/Hr (Qts) |
Moderate Work/Rest (Minutes) |
Water Intake/Hr (Qts) |
Hard Work/Rest (Minutes) |
Water Intake/Hr (Qts) |
---|---|---|---|---|---|---|---|
0 | < 78 | NL | N/A | NL | N/A | NL | N/A |
1 | 78-81.9 | NL | 1/2 | NL | 3/4 | 40/20 | 3/4 |
2 | 82-84.9 | NL | 1/2 | 50/10 | 3/4 | 30/30 | 1 |
3 | 85-87.9 | NL | 3/4 | 40/20 | 3/4 | 30/30 | 1 |
4 | 88-89.9 | NL | 3/4 | 30/30 | 3/4 | 20/40 | 1 |
5 | > 90 | 50/10 | 1 | 20/40 | 1 | 10/50 | 1 |
N/A - Not Applicable
NL - No Limit
Definitions
Easy Work | Moderate Work | Hard Work |
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- The work/rest time and fluid replacement volumes will sustain performance and hydration for at least 4 hours of work in the specified heat category. Individual water needs will vary ± ¼ qt/hr.
- NL= no limit to work time per hour.
- Rest means minimal physical activity (sitting or standing) and should be accomplish in shade if possible.
CAUTION
- Hourly fluid intake should not exceed 1 ½ quarts.
- Daily fluid intake should not exceed 12 quarts.
- Wearing body armor adds 5°F to WBGT index.
- Wearing MOPP over garment adds 10°F to WBGT Index