Evaluation and refinement of the environmental stress index for different climatic conditions.
The purpose of this study was to evaluate the recently constructed environmental stress index (ESI) for a large database comprising various climatic conditions. Data analysis of measurements from 19 locations revealed a high correlation between ESI and the wet bulb globe temperature (WBGT) index for each database. Validity from statistical analysis, including optimization procedures, slightly changed the ESI constants as follows: ESI = 0.62Ta - 0.007RH + 0.002SR + 0.0043(Ta x RH) - 0.078(0.1 + SR)(-1) where: Ta = ambient temperature (degrees C); RH = relative humidity (%); and SR = solar radiation (w x m(-2)). The refined ESI and the WBGT index were applied to databases of more than 125,000 measurements for each variable: Ta, RH, SR, black globe temperature (Tg), and wet bulb temperature (Tw). For each database, the ESI was then successfully correlated with the WBGT (P < 0.05, R2 > or = 0.899). We conclude that the refined ESI, which is constructed from fast response and commonly used weather sensors (Ta, RH, SR), is a potential index to serve as an alternative to the WBGT for heat category assessment.
Moran
D S
DS
Heller Institute of Medical Research, Sheba Medical Center Tel Hashomer 52621, Israel. dmoran@sheba.health.gov.il
Pandolf
K B
KB
Laor
A
A
Heled
Y
Y
Matthew
W T
WT
Gonzalez
R R
RR
D000064:Acclimatization; D000465:Algorithms; D001833:Body Temperature Regulation; D002980:Climate; D016208:Databases, Factual; D004777:Environment; D006358:Hot Temperature; D006801:Humans; D006813:Humidity; D011834:Radiation Monitoring; D013312:Stress, Physiological / Q000503:physiopathology*; D013696:Temperature; D013697:Thermosensing; D013997:Time Factors