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| Two methods to depict the thermoneutral zone. a , The classical method indicating the dependence of metabolic rate versus operative temperature. b , The method used in this paper describing the relation between skin temperature versus operative temperature. The range to the left of the thermoneutral zone depicted with ‘shivering’ indicates that more heat production is required to maintain thermal balance, and the range to the right depicted by ‘sweating’ indicates that more heat loss is required to maintain thermal balance. Within the open bounds it is possible for the body to maintain core temperature. 

| Two methods to depict the thermoneutral zone. a , The classical method indicating the dependence of metabolic rate versus operative temperature. b , The method used in this paper describing the relation between skin temperature versus operative temperature. The range to the left of the thermoneutral zone depicted with ‘shivering’ indicates that more heat production is required to maintain thermal balance, and the range to the right depicted by ‘sweating’ indicates that more heat loss is required to maintain thermal balance. Within the open bounds it is possible for the body to maintain core temperature. 

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... the built environment is focusing more on design of energy- efficient buildings (for example, near-zero-energy buildings), we argue that indoor climate standards should accurately represent the thermal demand of all occupants. Otherwise there is a great risk that occupants will adapt their behaviour to optimize personal comfort, which may in turn nullify the effects of supposed energy-efficient designs. Furthermore, various fields in commerce, science and policymaking depend on accurate predictions of building energy consumption. For instance, commercial incentives for building renovations premised on energy-saving predictions; scientific climate change simulations require building energy consumption predictions to account for warming effects in winter 4 ; and policymaking for resource management requires integrated resource assessments including energy consumption by buildings 5 . The total variation in building energy consumption that is explained by occupant behaviour includes operating the thermostat, windows or air conditioning system 1 . In general, females prefer a higher room temperature than males in home and office situations, and mean values may differ as much as 3 K (males: 22 ◦ C versus females: 25 ◦ C; refs 6,7). Despite this discrepancy in preferred room temperature, no significant gender effect is found with respect to the mean skin temperature range that is associated with thermal comfort (males: 32.8–33.8 ◦ C versus females: 32.4–33.6 ◦ C; ref. 8). Indoor thermal environment design is primarily based on PMV/PPD (predicted mean vote/percentage people dissatisfied) criteria. The PMV is expressed on the ASHRAE 7-point Thermal Sensation Scale ranging from cold ( − 3) to hot ( + 3). This vote is linked to thermal discomfort through the PPD (ref. 9). Two main input variables for the model are metabolic rate and clothing insulation; however, the accuracy of these variables is in general poorly defined 10,11 . Nevertheless, standard reference values for the metabolic rate and clothing are tabulated and used worldwide 2,12,13 . With respect to the metabolic rate, the metabolic equivalent (MET) is used to express the metabolic cost of an activity relative to the resting metabolic rate, and its value (1 MET = 4.186 kJ kg − 1 h − 1 ≈ 58 W m − 2 ) is set by convention based on the resting metabolic rate of only one 70 kg, 40-year-old male 3 . This may have significant consequences because 58 W m − 2 may overestimate resting heat production of women up to 35% (ref. 3). Similarly, with increasing age, basal metabolic rate decreases 14 . Thus, current indoor climate standards may intrinsically misrepresent thermal demand of the female and senior subpopulations 10,15 . The PMV/PPD model uses the metabolic rate to calculate the environmental conditions that satisfy thermal balance between the body and the environment (see Fig. 1, right part: skin to environment). However, from a biophysical perspective, thermal balance within the body has to be satisfied as well (see Fig. 1). Thermal balance within the body is dictated by both metabolism and the composite thermal insulation provided by tissues (that is, body composition and skin blood flow). The influence of thermal insulation is especially relevant in the case of lean versus obese. The larger insulation provided by adipose tissue results in greater core-to-skin temperature gradient and a lower mean skin temperature for obese compared with lean 16 . Consequently, these physiological characteristics co-determine the thermal demand from the environment. The PMV/PPD model was published in the 1970s and at that time biophysical models that incorporate the influence of tissue insulation were not widely used. However, since that time several biophysical models of human thermal balance have been developed 17–19 . Therefore, the knowledge gained from these models could be used to enhance the PMV/PPD model. It has been suggested that thermal balance within the thermoneutral zone is a prerequisite of steady-state thermal comfort 20 . The thermoneutral zone is defined in physiological terms as the range of operative temperatures where an organism can maintain its body temperature without regulatory changes in metabolic rate (for example, shivering or non-shivering thermogenesis) or sweating 21 (see Fig. 2). In relation to thermal comfort this means that operative temperatures that are thermally comfortable (thermal comfort zone) coincide with, or at least form a subset of, the temperatures where the body requires no regulatory metabolic heat production or sweating to maintain thermal balance (thermoneutral zone) 20,22 . The exact positioning of the thermoneutral zone may thus change with activity, body composition (tissue insulation) and clothing level. In this study we investigate the thermal state of young adult females performing light office work and we use a biophysical modelling approach to test whether these thermal states fall within their thermoneutral zone (see Methods and Supplementary Table). With this analysis we aim to point out the importance of using the actual metabolic rate, instead of a standard one based only on a male. Therefore, the biophysical model may provide a constructive way forward from the empirical thermal comfort standard. The measured group average metabolic rate for young adult females while performing light office work is 48 ± 2 W m − 2 , which is significantly lower ( p < 0.01) than the ASHRAE standard values for metabolic heat production associated with this activity (from resting seated: 60 W m − 2 or 20% overestimation, to seated filing: 70 W m − 2 or 32% overestimation). The biophysical analyses using both the measured and range of reference values for metabolic rate is shown in Fig. 3 (see Methods for details on how this Figure is constructed). The grey areas in Fig. 3 indicate the thermoneutral zones; that is, they depict the area where heat loss equals measured metabolic heat production. Open circles indicate actually measured mean skin temperature and operative temperature baseline recordings. When using the measured metabolic rate (Fig. 3, right area), measurements are located inside the thermoneutral zone. This is in great contrast to where all model parameters are kept equal except for the metabolic rate for which the standard reference values for light office work are used (Fig. 3, left area). This biophysical analysis shows that mean skin temperature and thermal environment of young adult females performing light office work falls within their thermoneutral zone, but only if the correct (actual) metabolic rate is used. Furthermore, we confirm that the metabolic rate of young adult females performing light office work is significantly lower than the standard values for the same type of activity. With these results we argue that the current metabolic standards should be adjusted by including the actual values for females to reduce gender-discriminating bias in thermal comfort predictions, and consequently, to reduce prediction bias in building energy consumption. The body senses its thermal state through temperature-sensitive receptors in core and skin tissues 20 . Various studies have examined skin temperatures that are associated with thermal comfort, and estimates range from wide (31.5 ≤ T s ≤ 35.5 ◦ C) to more conservative (32.4 ≤ T s ≤ 33.6 ◦ C) values 8,23 . The former seems to coincide with the entire thermoneutral zone of young adult females performing light office work (see 31.5 ≤ T s ≤ 35.5 ◦ C, Fig. 3), whereas the latter comprises only a subset of the thermoneutral zone (see 32.4 ≤ T s ≤ 33.6 ◦ C, Fig. 3). This discrepancy between studies may in part have been caused by differing number of skin sites that have been measured. In general, more skin sites yields more reliable results. Using a standard that consists of less than 10 skin sites leads to significantly lower reliability 24 . On top of that, within limits imposed by physics and physiology, human psychological factors (for example, thermal adaptation due to geography) may also play a role in what skin temperatures are considered comfortable 25 . Constraining the model results further to skin temperatures that are associated with thermal comfort it is possible to identify a biophysical thermal comfort zone 22 . For the given conditions, the biophysical thermal comfort zone for females ranges from 23.2 to 26.1 ◦ C (for mean skin temperature ranging 32.4 ≤ T s ≤ 33.6 ◦ C). As introduced, we make a case to use more reliable values for female metabolic rate in thermal comfort prediction. Future technological advances may yield devices that accurately measure individual metabolic rate (for example, via smart watches and so on). Until that time, one way to go forward may be by using resting metabolic rate equations that take into account the effects of age, sex and body size (for example, revised Harris and Benedict equations for resting metabolic rate 26 ). The resting metabolic rate can be converted from watt to watt per square metre by using the appropriate equation for body surface area (for example, ref. 27). Furthermore, the resting metabolic rate can also be scaled to the activity type using the MET scaling factors. The use of more accurate metabolic rates implies that the PMV/PPD ...

Citations

... Often, people need to put on an additional layer of clothes if sitting at their desk for extended periods. This is especially common for women, as described in [4] and [5]. These studies find that females prefer higher room temperatures than males, based on large scale field surveys and actual metabolic rate through biophysical analysis. ...
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The smart control informed by IoT sensors and enabled by remotely controlled devices can optimize the building operation to minimize unnecessary energy consumption and improve indoor thermal comfort. This paper quantifies the potential for electricity savings in small office buildings from smart thermostat control and occupancy-informed smart plug control. This is done by simulating the effect of adaptive setpoint temperature, occupancy-based HVAC control, and night-purge free cooling on small office buildings across all major climate zones in the United States. Adopting these smart control measures can achieve 8.9% to 20.4% of savings in total electricity consumption of small office buildings, or equivalent to annual reductions between 12.2 kWh/m2 and 30.4 kWh/m2 in electricity usage intensity. Among all climate zones, the hot and dry climates benefit the most from proposed smart controls and achieve the highest percentages of electricity savings
... In the highlevel temperature areas, the memory scores of females were higher than that of males, while in the low temperature areas, memory scores were not significantly different between the two genders. This is consistent with previous studies [16], which may be due to the fact that female generally prefer higher indoor temperatures than males [53,54]. ...
... In the high-level temperature areas, the memory scores of females were higher than that of males, while in the low temperature areas, memory scores were not significantly different between the two genders. This is consistent with previous studies [16], which may be due to the fact that female generally prefer higher indoor temperatures than males [53,54]. ...
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Individual, meteorological, and environmental factors are associated with cognitive function in older age. However, little is known about how meteorological and environmental factors interact with individual factors in affecting cognitive function in older adults. In the current study, we used mixed effects models to assess the association of individual, meteorological, and environmental factors with cognitive function among older adults in urban areas. Data from 2623 adults aged 60 to 91 years from 25 provinces (or autonomous regions/municipalities) from the China Family Panel Studies (CFPS) were used. We used the memory test in CFPS to measure memory function, while meteorological data from the daily climate data set of China’s surface international exchange stations, and the traffic and greening data compiled by the National Bureau of Statistics (NBS) of China, were used to assess meteorological and environmental factors. The ICC of the empty model indicated that 7.7% of the variation in memory test scores for the older adults was caused by provincial characteristics. Results showed that the temperature and relative humidity of provinces moderated the effect of gender on the memory function for the older urban adults. Specifically, in the high temperature areas, memory scores for females were higher than those of males, and in the middle humidity areas, memory scores were also higher for the females than those of males. This study explained how meteorological and environmental factors played roles in influencing demographic factors on memory function among older adults. Further research is needed to better define the role and potential mechanism of this moderation.
... However, achieving consistent thermal comfort for all individuals in a shared environment is challenging, due to the variability of individual thermal physiology and preferences (Richard & Gail Schiller, 1998). As few as 11% buildings have 80% or more participants expressing satisfactory thermal comfort , which affects motivation and performance (Cui et al., 2013) and gender equality (Irfan, 2015;Kingma & Van Marken Lichtenbelt, 2015). ...
Article
Thermal physiology and psychophysics are complex and nuanced, with significant variability between individuals. Wearable devices have the potential to offer customizable microclimate control. However, individual experiences with different supplemental heating strategies are likely to vary considerably in unconstrained environments. The physiological responses, psychophysical effects, and qualitative experiences of participants using five readily available heating strategies were collected in a quasi-field study environment ( n=17). Although all devices maintained or increased fingertip temperature, effects observed from controlled studies of thermal physiology are not clearly seen. Physiological, perceptual, and experiential data are presented, exploring heating technologies and thermal comfort in typical indoor environments.
... Although this has been recognised for some time, it continues to be a problem. Research shows that basing a building's environmental requirements only on the male metabolic rate may mean they could be 'intrinsically non-energy-efficient in providing comfort to females' [30]. Thus, even within the human species, the idea of 'quality' is contested and environments privilege certain stakeholders and disadvantage others. ...
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The article explores how the quality of life within a deprived urban environment might be improved through the ‘gamification’ of and interaction with, more-than-human elements within the environment. It argues that such quality may be achieved through the community’s multicentered value from the bottom up. This is shown through the case study of the Co-De|GT urban mobile application that was developed in the Synergetic Landscapes unit through real-life research by design experimental studio teaching. Complimentary experimentation took place during the Relating Systems Thinking and Design 10 symposium in the Co-De|BP workshop, where experts were able to be collocated for interactive real-time data gathering. This application addresses the need for collective action towards more-than-human synergy across an urban ecosystem through gamification, community collaboration and DIY culture. It intends to generate a sustainable, scalable token economy where humans and non-humans play equal roles, earning, trading and being paid for goods and services to test such potentials for future economies underpinned by blockchain. This work diverges from dominant economic models that do not recognise the performance of and the limits to, material extraction from the ecosystem. The current economic model has led to the global financial crisis (GFC). Furthermore, it is based on the unsustainable perpetual consumption of services and goods, which may lead to the untangling and critical failure of the market system globally. Therefore, this work investigates how gamification and tokenization may support a complementary and parallel economic market that sustains and grows urban ecosystems. While the research does not speculate on policy implications, it posits how such markets may ameliorate some of the brittleness apparent in the global economic model. It demonstrates a systemic approach to urban ecosystem performance for the future post-Anthropocene communities and economies.
... Previous research has consistently found that females are more sensitive to temperature change than males [6,7,96,97]. Females tend to feel cooler than males in cool/cold environments, but few gender differences were found in thermal comfort responses to neutral and slightly warm environments [96]. ...
Article
Personal comfort systems (PCSs) that are energy efficient have been widely used indoors to improve occupant thermal comfort and acceptability under a variety of thermo-hygrometric conditions. Although numerous studies have shown that the use of PCSs has beneficial effects, definitive conclusions on the effectiveness of PCSs on thermal comfort enhancement have yet to be drawn. Furthermore, detailed analyses of specific indoor conditions that may be the most promising are lacking. As a result, a comprehensive meta-analysis review was conducted to summarize, analyze, and compare findings from eligible documented studies on the effects of various PCSs on occupants’ perceptual responses. Besides, the energy performance of various PCSs was examined. The effects of total cooling or heating area as well as types of PCSs, on occupants’ perceptual responses were specifically addressed. This systematic review and meta-analysis serve as a foundational reference source for the selection of highly energy-efficient and effective personal comfort systems to improve thermal comfort of indoor occupants.
... Individual differences, such as personal factors like race, gender, age, weight, etc., can cause different metabolic rates as indicated in [50,51]. The experiments in this study were conducted with only Turkish subjects. ...
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Thermal comfort depends on four environmental parameters such as air temperature, mean radiant temperature, air velocity and relative humidity and two personal parameters, including clothing insulation and metabolic rate. Environmental parameters can be measured via objective sensors. However, personal parameters can be merely estimated in most of the studies. Metabolic rate is one of the problematic personal parameters that affect the accuracy of thermal comfort models. International thermal comfort standards still use a conventional metabolic rate table which is tabulated according to different activity tasks. On the other hand, ISO 8996 underestimates metabolic rates, especially when the time of activity level is short and rest time is long. To this aim, this paper aims to determine metabolic rates from physical measurements of heart rate, mean skin temperature and carbon dioxide variation by means of nineteen sample activities. 21 male and 17 female subjects with different body mass indices, sex and age are used in the study. The occupants are subjected to different activity tasks while heart rate, skin temperature and carbon dioxide variation are measured via objective sensors. The results show that the metabolic rate can be estimated with a multivariable non-linear regression equation with high accuracy of 0.97.
... Questões como: difi culdades com a temperatura ambiente (tipicamente banalizada nas organizações, como apontam Kingma & van Marken Lichtenbelt, 2015); trabalho de cuidado afetivo e de apoio operacional esperado das mulheres, invisibilizado nas organizações, mas que cria problemas na organização do trabalho, principalmente para o crescimento das mulheres (Dorna & Muniz, 2018); desenho de progressões funcionais e outras modalidades de reconhecimento que não considerem períodos como licença maternidade (Leal et al., 2017); cargos de chefi a cuja ocupação é inviável para uma mulher (Yannoulas, 2011); relações socioprofi ssionais marcadas por expectativas ambivalentes de docilidade e força, desde que não ameace o lugar da masculinidade (Molinier, 2004). Todas são exemplos de como há estruturas específi cas a serem contempladas nas clínicas, que são, geralmente, diluídas em outros aspectos mais "gerais" do contexto de trabalho. ...
... Las diferencias en el confort térmico entre hombres y mujeres se han atribuido a factores fisiológicos, como las características corporales y el sistema endocrino (Kaciuba-Uscilko y Grucza, 2001;Kingma et al., 2012). En Holanda, los estudios en cámara climática realizados por Kingma y Van Marken Lichtenbelt (2015), identificaron que las diferencias metabólicas (W/m 2 ) de las participantes (una población homogénea de 16 mujeres jóvenes con características físicas similares), con relación a los valores establecidos en la ASHRAE 55 -basados en hombres-fueron entre -20 % y -32 %, según la actividad física. De acuerdo con lo anterior, si el índice Voto Medio Estimado o PMV es usado para acondicionar un ambiente ocupado por hombres y mujeres, la gran insatisfacción térmica reportada por las mujeres podría ser explicada. ...
... De acuerdo con lo anterior, si el índice Voto Medio Estimado o PMV es usado para acondicionar un ambiente ocupado por hombres y mujeres, la gran insatisfacción térmica reportada por las mujeres podría ser explicada. Los autores sugieren recalibrar el modelo PMV con las tasas metabólicas de cada subpoblación (Kingma y van Marken Lichtenbelt, 2015). ...
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... Reasons for higher dissatisfaction in cold temperatures for women have been attributed to physiological and clothing differences. A biophysical analysis showed an underestimation of the metabolic rate of women in the heat-balance model codified by international thermal comfort standards 16 . The outcome of a systematic error like this would be the specification of cooler temperatures that align with the typical metabolic heat produced by men. ...
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Growth in energy use for indoor cooling tripled between 1990 and 2016 to outpace any other end use in buildings. Part of this energy demand is wasted on excessive cooling of offices, a practice known as overcooling. Overcooling has been attributed to poorly designed or managed air-conditioning systems with thermostats that are often set below recommended comfort temperatures. Prior research has reported lower thermal comfort for women in office buildings, but there is insufficient evidence to explain the reasons for this disparity. We use two large and independent datasets from US buildings to show that office temperatures are less comfortable for women largely due to overcooling. Survey responses show that uncomfortable temperatures are more likely to be cold than hot regardless of season. Crowdsourced data suggests that overcooling is a common problem in warm weather in offices across the US. The associated impacts of this pervasive overcooling on well-being and performance are borne predominantly by women. The problem is likely to increase in the future due to growing demand for cooling in increasingly extreme climates. There is a need to rethink the approach to air-conditioning office buildings in light of this gender inequity caused by overcooling.
... More research is needed to fully understand the gender differences in cooling demand for facial and neck cooling using wearable fans. Females are more sensitive to temperature change than males, according to documented research [43,44]. In thermal comfort responses to slightly warm environments, there were few gender differences [43]. ...
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Face and neck cooling has been found effective in improving thermal comfort during exercise in the heat despite the fact that the surface area of human face and neck regions accounts for only 5.5% of the entire body. Presently very little documented research has been conducted to investi-gate cooling the face and neck only to improve indoor thermal comfort. In this study, two highly energy efficient wearable face and neck cooling fans were used to improve occupant thermal comfort in two warm indoor conditions (30 & 32 °C). Local skin temperatures and perceptual re-sponses while using the two wearable cooling fans were examined and compared. Results showed that both cooling fans could significantly reduce local skin temperatures at the forehead, face and neck regions by up to 2.1 °C. Local thermal sensation votes at the face and neck were de-creased by 0.82-1.21 scale unit at the two studied temperatures. Overall TSVs decreased by 1.03-1.14 and 1.34-1.66 scale units at 30 and 32 °C temperatures, respectively. Both cooling fans could raise the acceptable HVAC temperature setpoint to 32.0 °C, resulting in a 45.7% energy saving over the baseline HVAC setpoint of 24.5 °C. Furthermore, occupants are advised to use the free-control cooling mode when using those two types of wearable cooling fans to improve ther-mal comfort. Finally, despite some issues on dry eyes and dry lips associated with those weara-ble cooling fans, it is concluded that those two highly energy-efficient wearable cooling fans could greatly improve thermal comfort and save HVAC energy.