Abstract
Thermal sensation and heat stress potential were evaluated in summer in an outdoor arid environment. Such evaluation had never been made in arid regions. Various scales: the temperature humidity index (THI), physiological effective temperature (PET), universal thermal climatic index (UTCI) and standard effective temperature (SET*) were used for the evaluation. Ray Man software model was used to estimate the PET and SET* and the UTCI-calculator was used for UTCI. The required air dry and wet bulb temperatures (T-d, T-w), solar radiation flux (S-0) and wind speed (V) were measured in summer (April 29-July 15). The results showed that: Persons are exposed to strong heat stress and would feel very hot most of the day time; and they are safe from heat stress risk and would feel comfortable most of the night time. Heat stress levels can be determined using the PET or UTCI scales; both are valid for arid environment and their results are almost similar; however, the THI cannot be used. SET* index specifically describes the thermal sensations and discomfort conditions along with summer days at any activity under arid conditions.