## 1 Introduction
Then, age, gender, body mass, and ethnicity are personal variables that modulate the metabolic heat dissipation process, which directly influences human thermal comfort [12]. Moreover, some of them are associated with differences in sensitivity to heat and cold, which are directly linked to a person's comfort zone. For instance, younger ages are more sensitive to cold [11] and heat. When considering different standards, guidelines, and handbooks, the metabolic rate also depends on physical activity and clothing [13]. Another critical parameter influencing human thermal comfort is environmental stimulation, notably represented by the vegetation, quantity and shape of buildings, and urban morphology. [PERSON] et al. [14] revealed that an analysis of vegetation elements showed a benefit in the Physiological Equivalent Temperature (PET) of 7-8 \({}^{\circ}\)C during the midday/afternoon period. They have also demonstrated that high-rise buildings' shadow can decrease by 12 \({}^{\circ}\)C. Finally, they stated that, during nighttime, sites in low-rise developments showed a lower temperature (1.2-1.5 \({}^{\circ}\)C) than high-rise areas, in agreement with a higher sky view factor and higher heat release. These results could be interpreted as the need to modify the PET indicator, as proposed by some authors [15]. The adaptation phenomenon is a complex but unneglected factor that influences human thermal comfort, and it has even led to the development of adaptive thermal comfort models [16]. Three different types of human adaptation could be distinguished: behavioral, physiological, and psychological [17]. The acceptable thermal range under outdoor conditions strongly differs from the one under indoor conditions in the same region and in the same context of climate and culture. Thus, two different studies in Tehran during the cold season demonstrate that the outdoor neutral temperature is around eight \({}^{\circ}\)C less than the indoor one [11]. This difference mainly arises from a different impact of climatic variables in these two types of spaces, psychological aspects, the discrepancy in clothing insulation values, activity level, and exposure time. Since outdoor thermal comfort is impacted by more factors, greater variability, and more interactions between them, its estimation requires different and much more complex models than those used for indoor thermal comfort. However, extreme heat waves have generated the emergence of the concept of thermal resilience [18]. This thermal resilience of people is the ability to withstand heat stress and be strengthened by it. [19]. This thermal resilience extends the band of acceptability, which relaxes the comfort requirements. [PERSON] et al. [20] demonstrate in their review the variability of results and how the perception of comfortable conditions of people differs from the standards proposed in the literature. These results motivate the work proposed in this article: to characterize the range of true acceptability of citizens accustomed to the thermal stress of the hot summers of this climatic region. A thermal comfort model aims to predict how comfortable a person is in a certain space taking into account its thermal, physiological, and psychological response to environmental stimulations. Then, a comfort index is often developed following the model. Different regulations and standards exist for addressing thermal comforts, such as ASHRAE 55 [10] and EN16798 [21]. However, they provide technical guidelines for indoor spaces only [22], and the development of some thermal models that could be applied in outdoor conditions used them as a basis. It's the case of the COMFA model, which was proposed by [PERSON] and [PERSON] [23]. This model is based on the energy balance equation and assigns a comfortable sensation to the value of the energy budget. It is a direct indicator since it can be obtained through an essential measurement of environmental conditions [24]. In addition, many authors, such as [PERSON] et al. ([PERSON] et al., 2009a, 2009b) and [PERSON] et al.