EFFECTIVE TEMPERATURE SCALE AND ITS MODIFICATIONS.
Abstract
Although empirically derived from immediate thermal sensations, the Effective Temperature scale shows agreement with physiological responses to the thermal environment over a wider range of temperature conditions than scales whose application is limited to the thermoregulatory zone of evaporative cooling. Simplicity in its application is a further advantage. For practical purposes the Corrected Effective Temperature of Bedford using the globe temperature in place of the dry bulb temperature takes adequate account of the additional stress imposed by radiant heat loads. Although theoretically better founded, the Effective Temperature Including Radiation (ETR) of Yaglou which requires correction of the wet bulb for the observed dew point and correction of the globe temperature for absorptivity of clothing is not significantly different from the CET when derived from the same environmental data. The Wet Bulb-Globe Temperature (WBGT) Index of Yaglou is a simplified version of the Effective Temperature scale corrected for radiation. No direct measurement of wind velocity is required. Within the range of natural environmental heat stress conditions for which it was intended the WBGT index shows close agreement with the CET and ETR. Evaporative heat loss as a measure of physiological strain correlates equally well with all three of these indices of heat stress. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 12, 1964
- Accession Number
- AD0603186
Entities
People
- David Minard
Organizations
- Naval Medical Research Center