13
12
Figure 4: Work/Rest ratios and Water Consumption Guidelines. (Source: U.S. Army Center for Health
Promotion and Preventive Medicine Health Information Operations Division.
URL: http://safety.ucanr.org/files/2091.pdf)
• The work/rest times and fluid
replacement volumes will sustain
performance and hydration for
at least 4 hrs of work in the
specified heat category. Fluid
needs can vary based on
individual differences (± ¼ qt/hr)
and exposure to full sun or full
shade (± ¼ qt/hr).
•
NL
= no limit to work time per hr.
•
Rest
= minimal physical activity
(sitting or standing) accomplished
in shade if possible.
•
CAUTION: Hourly fluid intake
should not exceed 1½ qts.
Daily fluid intake should not
exceed 12 qts.
• If wearing body armor, add
5°F
to
WBGT index in humid climates.
• If doing Easy Work and wearing
NBC (MOPP 4) clothing, add
10°F
to WBGT index.
• If doing Moderate or Hard Work
and wearing NBC (MOPP 4)
clothing, add
20°F
to WBGT
index.
Work/Rest and Water Consumption Table
Applies to average sized, heat-acclimated soldier wearing BDU, hot weather. (See TB MED 507 for further guidance.)
Heat
Category
WBGT
Index, Fº
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
78º - 81.9º
NL
½
NL
¾
40/20 min
¾
2
(
GREEN
)
82º - 84.9º
NL
½
50/10 min
¾
30/30 min
1
3
(
YELLOW
)
85º - 87.9º
NL
¾
40/20 min
¾
30/30 min
1
4
(
RED
)
88º - 89.9º
NL
¾
30/30 min
¾
20/40 min
1
5
(
BLACK
)
> 90º
50/10 min
1
20/40 min
1
10/50 min
1
Easy Work
Moderate Work
Hard Work
• Weapon Maintenance
• Walking Hard Surface at 2.5 mph,
< 30 lb Load
• Marksmanship Training
• Drill and Ceremony
• Manual of Arms
• Walking Loose Sand at 2.5 mph,
No Load
• Walking Hard Surface at 3.5 mph,
< 40 lb Load
• Calisthenics
• Patrolling
• Individual Movement Techniques,
i.e., Low Crawl or High Crawl
• Defensive Position Construction
• Walking Hard Surface at 3.5 mph,
≥ 40 lb Load
• Walking Loose Sand at 2.5 mph
with Load
• Field Assaults
For additional copies, contact: U.S. Army Center for Health Promotion and Preventive Medicine Health Information Operations Division
at (800) 222-9698 or CHPPM - Health Information Operations@apg.amedd.army. mil.
For electronic versions, see http://chppm-www.apgea.army.mil/heat. Local reproduction is authorized.
June 2004
CP-033-0404
For additional copies, contact: U.S. Army Center for Health Promotion and Preventive Medicine Health Information Operations Division at (800)
222-9698 or CHPPM - Health Information Operations@apg.amedd.army. mil. For electronic versions, see http://chppm-www.apgea.army.mil/heat.
Local reproduction is authorized. June 2004
GUIDANCE FOR HIGH SCHOOL ATHLETICS
WBGT READING
ACTIVITY GUIDELINES & REST BREAK GUIDELINES
UNDER 82.0
82.0 - 86.9
87.0 - 89.9
90.0 - 92.0
OVER 92
Normal activities - Provide at least three separate rest breaks
each hour of minimum duration of 3 minutes each during workout.
Use discretion for intense or prolonged exercise; watch at-risk players
carefully; Provide at least three separate rest breaks each hour of a
minimum of four minutes duration each.
Maximum practice time is two hours! 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 at least four separate rest breaks each hour of a minimum of
four minutes each.
Maximum length of practice is one hour, no protective equipment may
be worn during practice and there may be no conditioning activities.
There must be 20 minutes of rest breaks provided during the
hour of practice.
NO OUTDOOR WORKOUTS! Cancel exercise; delay practice until
a cooler WBGT reading occurs.
GHSA Heat Index Record Sheet. Georgia High School Athletic Association Heat Index Measurement and Record. 2012:1.
Figure 4
Figure 5
GUIDANCE FOR ATHLETIC TRAINERS
Green
Risk low but still exists on the basis
of risk factors.
WBGT
FLAG
COLOR
LEVEL OF
RISK
COMMENTS
Yellow
Red
Black
Low
Moderate
High
Extreme or
Hazardous
Risk level increases as event
progresses through the day.
Everyone should be aware of injury
potential; individuals at risk should
not compete.
Consider rescheduling or delaying the
event until safer conditions prevail; if the
event must take place, be on high alert.
Roberts WO. Medical management and administration manual for long distance road racing. In: Brown CH, Gudjonsson B, eds.
IAAF
Medical Manual for Athletics and Road Racing Competitions: A Practical Guide.
Monaco: International Amateur Athletic Federation
Publications; 1998:39–75.
<18 C (<65 F)
o
o
18-23 C (65-73 F)
o
o
23-28 C (73-82 F)
o
o
>28 C (82 F)
o
o
Guidance for heat-acclimated soldiers
LIGHT
ISO 7243 THRESHOLD LIMIT VALUES FOR WORK ENVIROMENTS
WORK-REST
REGIMEN
WORK LOAD
o
C F
o
o
C F
o
o
C F
o
MODERATE
HEAVY
30.0
30.6
31.4
32.2
86.0
87.1
88.5
90.0
26.7
28.0
29.4
31.1
80.1
82.4
84.9
88.0
25.0
25.9
27.9
30.0
77.0
78.6
82.2
86.0
Continuous work
75% work + 25% rest; each hour
50% work + 50% rest; each hour
25% work + 75% rest; each hour
Parsons, Ken. Heat Stress Standard ISO 7243 and its Global Application.
Industrial Health
2006(44):368-379.
WBGT
GUIDANCE FOR CHILDREN’S SPORTS PRACTICE
MODIFYING PRACTICE SESSIONS FOR EXERCISING CHILDREN
All activities allowed, but be alert for the prodromes of heat-related
illness in prolonged events.
RESTRAINTS ON ACTIVITIES
Longer rest periods in the shade; enforce drinking every 15 min.
Stop activity of unacclimatized persons and high-risk persons; limit
activities of all others (disallow long-distance races, cut the duration
of other activities.
Cancel all athletic activities.
Notes:
1. Source: reference (7).
2. These guidelines do not account for clothing. Although the effects of the uniform clothing and protective equipment
(i.e., American football) on sweating and body temperature in younger athletes are unknown, uniforms should be considered
when determining playing/practice limitations based on the WBGT.
3. Eight to 10 practices are recommended for heat acclimatization (30–45 min each; one per day or one every other day).
4. Differences of local climate and individual heat acclimatization status may allow activity at higher levels than outlined in the
table, but athletes and coaches should consult with sports medicine staff and should be cautious when exceeding these limits.
o
F C
o
<75.0 <24.0
75.0-78.6 24.0-25.9
79.0-84.0 26.0-29.0
>85.0 >29.0
American Academy of Pediatrics. Climatic heat stress and the exercising child and adolescent.
Pediatrics
106(1):158–159, 2000.
In addition to utilizing the guidance that is applicable to your environment
and/or event, please refer to YOUR SPECIFIC STATE’S REQUIREMENTS for
measuring WBGT and heat acclimatization guidelines.
Figure 6
Figure 7
Figure 8
