Campbell BlackGlobe, Инструкция по эксплуатации

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Appendix A. The Theory of BlackGlobe
Temperature and Heat Stress
The Wet-Bulb Globe Temperature Index (WBGT) combines the effects of
temperature, humidity, radiant heat, and wind into one single index employed
to express environmental heat stress. Loss of physical and mental efficiency
occurs under definable degrees of heat stress. Severe heat stress can lead to
fatigue, exhaustion and possibly even disability or death. Personnel can
increase their resistance to heat stress by acclimatizing gradually to hot
environments and by maintaining a good water and salt balance.
Heat stress can be reduced by decreasing the lengths of exposure and
decreasing the workload of individuals under heat stress. Situational factors
such as the type of clothing worn, the type of work performed, the
psychological effects of stress, and the availability of fluids can also affect the
assessment of heat stress. These factors are not easily quantified, and so the
individual in a given situation must estimate their significance. Environmental
factors such as temperature, humidity, and wind are more easily measured to
assess heat stress. TABLE A-1 provides some guidelines for using the WBGT
index.
TABLE A-1. Sample use of WBGT Index
Readings Guidelines
WBGT Index
Reading 26 – 27.5 Precautions should be taken. Water intake should be a
minimum of 0.5 liters/hr. The work/rest cycle for an
acclimatized person should be 50/10 min/hr.
WBGT Index
Reading 27.5 – 29 Increased water intake should be emphasized. Water
intake should be 0.5 to 1 liters/hr. The work/rest cycle
for an acclimatized person should be 50/10 min/hr.
WBGT Index
Reading 29 – 31 Increased supervision of personnel performing physical
activity is required. Water intake should be 1 to 1.5
liters /hr. The work/rest cycle for an acclimatized person
should be 45/15 min/hr.
WBGT Index
Reading 31 – 32 Physical activity should be limited to a maximum of 6
hours per day for fully acclimatized personnel. Water
intake should be 1.5 to 2 liters/hr. The work/rest cycle
for an acclimatized person should be 30/30 min/hr.
WBGT Index
Reading >32 All strenuous activity should be suspended. Water
intake should be a minimum of 2 liters/hr. The
work/rest cycle for an acclimatized person (non-
strenuous activity) should be 20/40 min/hr.
A-1