Wet-bulb globe temperature index

Wet-bulb globe temperature Index a mathematical expression... 

Stafford Country Public Schools, Office of Safety Security (unknown year) Wet Bulb Globe Temperature Index (WBGT). Available at www.pen.kl2.va.us/Div/Stafford/Safety/wetbulb.html (accessed 13 April 2006). 

Wet-Bulb Globe Temperature Index Researchers developed the WBGT index as a simple-to-use method for determining if military troops were likely to suffer from heat illnesses in hot environments. The WBGT index requires only two or three measurements wet-bulb (static) temperature (WB), dry-bulb temperature (DB), and globe temperature (GT). One can compute WBGT values from one of two equations, depending on the presence of a solar load. 

The Wet Bulb Globe Temperature index (WBGT) can be calculated from the formula ... 

WBGT=Wet Bulb Globe Temperature Index NWB=Nature Wet-Bulb Temperature DB=Dry-Bulb Temperature GT=Globe Temperature... 

The ISO philosophy for the assessment of hot environments is to use a simple, fast method of monitoring the environment, based on the wet bulb globe temperature (WBGT) index (ISO 7243). If the WBGT value exceeds the provided reference value, or if a more detailed analysis is required, then ISO 7933 provides an analytical method of assessment. 

The most dismptive element of providing care for chemical casualties when wearing PPE is caused by heat stress and subsequent dehydration of the responder. To decrease heat stress, published tables provide work-rest cycles based on temperature being measured by the Wet Bulb Globe Temperamre Index (FM 3-11.4, June 2004). Careful adherence to these tables will decrease heat-related casualties among responders. This index considers the effects of temperature, humidity, radiant energy, and wind. It produces a temperature based on integration of the effects of the above four factors (Stafford County Public Schools, unknown year). 

A more complex and well-known climatic index is the Wet Bulb Globe Temperature (WBGT), used as a heat stress indicator. The WBGT is a composite temperature used to estimate the effect of temperature, humidity, and solar radiation on humans. It is used by industrial hygienists, athletes, and the military to determine appropriate exposure levels to high temperatures. It is derived from the following formula ... 

An index discussed later is the wet-bulb globe temperature (WBGT). When making wet-bulb readings for WBGT, the wet-bulb thermometer must be stationary and not involve moving air. 

Internahonal Standards Organization. (1982). International Standard 7243. Hot environments - Estimation of the heat stress on working man, based on the WBGT index (Wet bulb globe temperature). Geneva, ISO. Instrumentation and measurement see IS07726. 

WBGT = web-bulb globe temperature index NWBT = natural wet-bulb temperature DBT = dry-bulb temperature GT = globe temperature. 

Fig. 4.3 Unsafe Behavior Index (UBI) as a function of WB6T (Wet Bulb Globe Temperature) predicted second order regression for three different workloads (from Ramsey et al., 1983)...

Corrected effective temperature An empirical comfort index that uses the dry bulb, wet bulb, and globe temperatures and the relative air velocity in a space. 

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