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Personal Comfort Systems (PCS) hold the promise of simultaneously improving energy conservation and occupants' thermal comfort. Locally applied thermal radiation is one of the most common PCS strategies for cool ambient environments. This study examines the subjective impacts of different infrared wavelengths applied to distal body segments of human subjects sitting quietly in cool and neutral environments. Experiment participants were exposed to three different wavelengths (near-infrared, mid-to far-infrared, and far-infrared), each of approximately equal flux density, on the backs of hands, lower arms, and lower legs, in both neutral (26.0 °C operative temperature) and cool (21.5 °C operative temperature) ambient environments within the chamber. Skin temperature, along with subjective thermal sensation and thermal pleasure votes were recorded throughout each exposure experiment. In the cool environment, similar to the neutral environment, far-infrared radiation increased skin temperature more than near-infrared and elicited warmer subjective thermal sensations and thermal pleasure responses. Of the three distal body segments examined, the back of the hands was most sensitive to the different wavelengths and was associated with the strongest and fastest pleasure response at the onset of radiant heating during the cool ambient environmental exposures. These findings have implications for PCS design, suggesting that irradiating the back of the hand with far-infrared wavelengths at the onset of PCS use may maximize thermal comfort of sedentary occupants in cool ambient conditions for a given power input. • Reveals that wavelength dependence of thermal perception in cool environments. • Back of the hand is more thermally sensitive than lower legs and arms. • Far-infrared radiation heating induces warmer and more pleasant responses. • Far-infrared radiation heating can elicit spatial alliesthesia. • Most pronounced pleasure response occurs at the onset of far-infrared irradiation. [ABSTRACT FROM AUTHOR]

It has recently become clear that using adaptive thermal comfort models to determine setpoint temperatures is a successful energy-saving method. Global models like ASHRAE 55 and EN16798-1 have been used in recent experiments using adaptive setpoint temperatures. This work, however, has taken a different route by concentrating on a region-specific Australian adaptive comfort model. The goal is to compare the energy implications of the use of setpoint temperatures based on the Australian local comfort model compared to the worldwide adaptive ASHRAE 55 model to highlight the significance of choosing the most fitting comfort model for making accurate predictions. All of Australia's climate zones are taken into account, as well as mixed-mode building operation scenarios, current and future scenarios, namely the years 2050 and 2100 for Representative Concentration Pathways (RCP) 2.6, 4.5, and 8.5. It has been found that the Australian-model-based adaptive setpoint temperatures taking into account mixed-mode significantly lowers energy demand when compared to the ASHRAE 55 adaptive model (average energy-saving value of 63 %). Considering climate change, the Australian model has an average energy demand of 13–26 kW h/m2·year, and an average increase of 1–13 kW h/m2·year. In the case of ASHRAE 55 model, energy demand decreases in future scenarios and average values range between 3 and 11 kW h/m2·year. Therefore, setting setpoint temperatures in accordance with the Australian regional adaptive comfort model is a very efficient method for energy conservation. These differences raise awareness on the importance of the selection of the appropriate adaptive thermal comfort model. • ASHRAE 55 is more suitable than the Australian adaptive model in warm zones. • Setpoints based on an Australian adaptive model can reduce energy demand by 63 %. • ASHRAE 55 is more resilient to climate change with 6 % energy demand reduction. [ABSTRACT FROM AUTHOR]

Overheating is widespread across diverse building typologies. In the context of global warming, it is becoming increasingly problematic in naturally-ventilated dwellings in which air-conditioning is not an available option. Whilst CIBSE TM59 offers the most widely used overheating assessment criteria for naturally-ventilated homes, the criteria have not been rigorously tested against real-world observations made beyond temperate regions of the UK. With an aim to examine the applicability of the CIBSE TM59 overheating criteria to subtropical residential contexts, statistical analysis was performed on thermal comfort field data collected from 162 dwellings in Australia. Our dataset consisted of indoor temperature observations recorded in living and sleeping spaces across the two-year monitoring period, accompanied by householders' subjective evaluation of thermal comfort (both daytime and nocturnal) and sleep quality. The results of our analysis identified a significant gap between the overheating assessment criteria and actual householders' experience of thermal conditions in their homes. Whilst most of our sample dwellings were deemed 'overheated' according to CIBSE TM59, approx. 80 % of daytime and nocturnal thermal sensations collected from the householders indicated they were comfortable. Especially in bedrooms, CIBSE's static 26 °C upper temperature threshold was found to be too stringent to be applicable to naturally-ventilated homes in subtropical regions of Australia. Our analysis demonstrated that sleep thermal comfort and sleep quality remained unaffected well beyond CIBSE's 26 °C limit. This study calls for further research in diverse climatic, housing, demographic and cultural contexts. • Field testing of CIBSE TM59 overheating criteria in subtropical residential context. • Performed overheating assessment of living and sleeping spaces in 162 dwellings. • Identified gap between CIBSE criteria and actual householders' thermal experience. • CIBSE 26 °C fixed limit for bedrooms found to be too stringent for Australian homes. • Sleep thermal comfort and sleep quality unaffected beyond 26 °C. [ABSTRACT FROM AUTHOR]

Aging populations pose significant social challenges for many countries including China. The elderly spends most of their time inside built environments, so a better understanding of their thermal comfort indoors is important. This study investigated the perceptual and physiological responses of elderly subjects to different operative temperatures (21 °C, 25 °C, 28 °C and 31 °C). Their indoor thermal requirements were investigated, and results compared with those of young people. Sixteen healthy subjects aged 70+, including both males and females, participated in this experiment. In addition to thermal comfort perceptions, two physiological parameters, including skin temperature (local and mean) and electrocardiograph (ECG) were also monitored. Results showed that skin temperature and the ratio of LFnorm to HFnorm of ECG were sensitive to the ambient temperature. For comparative purposes, we refer to the previously published climate chamber experimental results of young college-age subjects also in Shanghai [1]. Neutral operative temperature (26 °C for a mean thermal sensation of " neutral ") and neutral skin temperature (32.2 °C for a mean thermal sensation of " neutral ") of the elderly sample in the present study was not different from that of young people. However, the elderly subjects were not as sensitive as the young college-age counterparts when it came to changes in operative temperature. • Perceptual and physiological responses of elderly were investigated. • No difference was found between the elderly and young people on neutral temperature. • The elderly subjects were not as sensitive as the young on temperature changes. [ABSTRACT FROM AUTHOR]

Highlights • Literature in thermal effects on performance from various disciplines is reviewed. • This synthesis converges on the inverted-U model and the extended-U model. • Strong theoretical and experimental research evidences favors the extended-U model. • The influential intervening factors and methodological discrepancies are discussed. • Extended-U model justifies indoor temperatures spanning the entire comfort zone. Abstract The effect of the thermal environment on performance and productivity has been a focus of interest among indoor environmental researchers for nearly a century, but most of that work has been conducted in relative isolation from the cognate disciplines of human performance evaluation. The present review examines thermal environmental effects on cognitive performance research conducted across multiple disciplines. After differentiating performance from productivity, we compare the two dominant conceptual models linking thermal stress to performance; (1) the inverted-U concept and (2) the extended-U relationship. The inverted-U specifies a single optimum temperature (or its corresponding subjective thermal sensation) at which performance is maximised. In contrast, the extended-U model posits a broad central plateau across which there is no discernible thermal effect on cognitive performance. This performance plateau is bounded by regions of progressive performance decrements in more extreme thermal conditions. The contradictions between these opposing conceptual models might derive from various confounding factors at play in their underlying research bases. These include, inter alia , environment-related, task-related, and performer-related factors, as well as their associated two-way and three-way interaction effects. Methodological discrepancies that might also contribute to the divergence of these conceptual models are evaluated, along with the proposed causal mechanisms underlying the two models. The weight of research evidence reviewed in this paper suggests that the extended-U hypothesis fits the relationship between moderate thermal environments and cognitive performance. In contrast to the inverted-U relationship, implemention of the extended-U in indoor climate control implies substantial reductions in building energy demand, since it permits the heating and cooling setpoint deadband to expand across the full width of the thermal comfort zone, or even slightly further during emergencies such as peak demand events on the electricity grid. Use of personal comfort systems can further extend the thermostat setpoint range beyond the comfort zone. [ABSTRACT FROM AUTHOR]

Abstract The quality of buildings can be assessed in terms of the indoor air quality, thermal comfort, lighting quality, acoustic comfort afforded the occupants, collectively referred to as Indoor Environmental Quality (IEQ). A major barrier to a more thoroughly representative audit of actual IEQ performance are the expense and complexity of the measurement instrumentation required. Rapid developments in sensor technology in recent years present the opportunity for continuous and pervasive IEQ monitoring to deliver truly representative characterisations of building performance at a modest cost. The last remaining obstacle to realising these developments seems to be a concern about instrument accuracy. In this paper we test the performance of a low-cost IEQ monitoring system (SAMBA) introduced in an earlier paper. Calibration data from 100 devices was analysed to calculate the standard error of the estimate as a measure of equipment accuracy. Those performance specifications were used in a Monte Carlo simulation based on measurements of thermal comfort parameters from 24 office buildings. Performance measures suggests the low-cost system, whilst not as accurate as laboratory equipment, is more than sufficient for building IEQ diagnostics and compliance assessments. Furthermore, the results of the Monte Carlo simulation show that continuous monitoring systems are better at characterising long-term performance than ad hoc measurement strategies using precision equipment. Low-cost pervasive monitoring technologies therefore offer a unique opportunity to improve our quantitative understanding of, and response to, indoor environmental quality issues. Highlights • Reviews standards for instrument specifications and IEQ measurement protocols. • Evaluates the performance of 100 low-cost continuous IEQ monitoring systems. • Monte Carlo methods test the performance of different sensors for continuous monitoring. • Show continuous monitoring is better than spot measurements for long-term comfort assessments. [ABSTRACT FROM AUTHOR]

Abstract Addressing two common challenges for building performance – reducing the carbon footprint attached to the provision of comfortable indoor environments, and improving the health and wellbeing of occupants – requires a more comprehensive understanding of how the indoor environments of buildings are operated. This paper introduces SAMBA, a state-of-the-art monitoring station for continuous, real-time measurements of indoor environmental quality (IEQ) parameters from occupants' work desks. It combines a hardware solution that integrates a low-cost suite of sensors with a software platform designed to automatically analyse and visualize data for quick interpretation of IEQ performance by non-scientist. In addition to feeding a massive IEQ database for research, the resulting data may be used to better inform the metrological requirements for popular international IEQ rating schemes. This new era of indoor environmental monitoring based upon systems such as SAMBA affords a fundamentally new approach to built environmental field research that holds significant promise to improve building performance and indoor environmental quality and occupant satisfaction, health, wellbeing and performance. Highlights • Discusses the technological innovations that have led to activity in IEQ monitoring systems. • Outlines the market drivers for low-cost continuous IEQ monitoring in offices. • Introduces a low-cost IEQ monitoring system for use in office buildings. • Details the sensor hardware and cloud software platform for data analysis and visualisation. [ABSTRACT FROM AUTHOR]

Thermal experiences in outdoor and semi-outdoor environments contribute significantly to the holistic experience of nature and its restorative benefits. Culture may be a significant factor influencing the large variations of human thermal perception in semi-outdoor and outdoor environments. This research aims to compare the differences in thermal pleasure, adaptive behaviours, and restorative benefits between two cultural groups, Chinese and Australian, undergoing identical exposures in semi-outdoor environments. Pretest-posttest experiments were conducted in climate chambers with 19 Chinese and 19 Australian participants. A multisensory immersive Virtual Reality method was adopted for the simulation of two semi-outdoor environmental scenarios, one providing only direct sunlight exposure and the other including the adaptive opportunity for subjects to select between direct sunlight or shade. When exposed to the sunlight-only scenario, most of the Chinese participants felt thermally unpleasant and engaged in sunlight avoidance behaviours, while majority of the Australian participants felt thermally pleasant and engaged in sunlight maximising behaviours. There were also significant differences in restorative benefits. Moreover, access to shade as an adaptive opportunity can potentially reduce cultural differences in thermal pleasure and restorative benefits resulting from outdoor exposures. Different notions of skin beauty between Chinese and Australian cultural groups (fair vs suntanned skin tone) may have contributed to divergent environmental attitudes regarding sunlight exposure, resulting in different thermal pleasure responses and adaptive behavioural patterns. The importance of culture-specific and inclusive design should be promoted by implementing adaptive design strategies to satisfy the diverse thermal preferences of semi-outdoor and outdoor users. • Cultural differences in thermal perception and adaptive behaviours are compared. • Sunlight approaching behaviours of Australians and avoidance behaviours of Chinese. • Adaptive opportunity alleviate cultural discrepancies in thermal pleasure. • Cultural backgrounds account for individual differences in restorative benefits. • Culture-specific and inclusive biophilic design strategies suggested. [ABSTRACT FROM AUTHOR]

Our aim was to compare the ambient temperature thresholds for warm thermal discomfort, thermal unacceptability, and preference for cooler environment between post- and pre-menopausal women at different metabolic rates. A total of 38 women (15 pre-menopausal (46 ± 5 years); 23 post-menopausal (55 ± 3 years)), completed up to 3 experimental trials at different metabolic rates (1.2 MET, 1.8 MET, 2.5 MET) generated by intermittent stepping throughout an air temperature ramp protocol. Ambient air temperature thresholds for warm thermal discomfort (thermal sensation rating of +1.5), warm thermal unacceptability, and a preference for a cooler environment, were determined. Skin temperature at 12 points was measured throughout. While a higher metabolic rate yielded a lower air temperature threshold for warm thermal discomfort (P < 0.001), there was no difference (P = 0.61) between pre-menopausal (28.7 ± 2.3 °C) and post-menopausal (28.5 ± 2.4 °C) women, irrespective of metabolic rate. The threshold of thermal unacceptability and the temperature at which a preference to be cooler was expressed were decreased by 1 °C, regardless of metabolic rate in post-menopausal women (P = 0.021; P = 0.049). Mean body T sk at the thresholds for warm thermal discomfort, thermal unacceptability, and preference for cooler temperature (all P > 0.05) did not differ between pre-menopausal and post-menopausal women. However, the forehead T sk thresholds for thermal unacceptability (pre-menopausal: 34.5 ± 1.1 °C; post-menopausal: 33.9 ± 1.2 °C; P = 0.005) and preference for cooler temperature (pre-menopausal: 34.2 ± 1.2 °C; post-menopausal: 33.7 ± 1.3 °C; P = 0.025) were lower in post-menopausal women. These data indicate that while the temperature threshold for warm thermal discomfort is unaltered by menopause status, post-menopausal women report an environment to be unacceptably warm, and express a preference for a cooler temperature, at a lower ambient and forehead skin temperature. • Menopause decreased the air temperature threshold for thermal unacceptability and preference. • Menopause decreased the forehead skin temperature for thermal unacceptability and preference. • Mean skin temperature did not influence thermal comfort, unacceptability, or preference. • Increased work decreased the thermal comfort, unacceptability, and preference thresholds. [ABSTRACT FROM AUTHOR]

Recognizing the value of open-source research databases in advancing the art and science of HVAC, in 2014 the ASHRAE Global Thermal Comfort Database II project was launched under the leadership of University of California at Berkeley's Center for the Built Environment and The University of Sydney's Indoor Environmental Quality (IEQ) Laboratory. The exercise began with a systematic collection and harmonization of raw data from the last two decades of thermal comfort field studies around the world. The ASHRAE Global Thermal Comfort Database II (Comfort Database), now an online, open-source database, includes approximately 81,846 complete sets of objective indoor climatic observations with accompanying “ right-here-right-now ” subjective evaluations by the building occupants who were exposed to them. The database is intended to support diverse inquiries about thermal comfort in field settings. A simple web-based interface to the database enables filtering on multiple criteria, including building typology, occupancy type, subjects' demographic variables, subjective thermal comfort states, indoor thermal environmental criteria, calculated comfort indices, environmental control criteria and outdoor meteorological information. Furthermore, a web-based interactive thermal comfort visualization tool has been developed that allows end-users to quickly and interactively explore the data. [ABSTRACT FROM AUTHOR]

Human individual differences widely and markedly affect thermal comfort and should be carefully considered in the design and operation of the built environment. This paper aims to list and examine the magnitude and significance of individual difference in the preferred/neutral/comfort temperature through reviewing previous climate chamber and field studies. Causal factors for individual differences are investigated, including sex, age and etc. There is no clear and consistent conclusions as to the significance and size of inter-group differences in thermal comfort (between females and males, or the young and the old). To address the issue of individual difference, a paradigm shift from centralized to personalized air condition is on the way with the following three steps: first, collecting individual physiological and psychological response; second, predict individual comfort with machine learning algorithms; and third, accommodating individual difference with Personalized Comfort Systems. [ABSTRACT FROM AUTHOR]

Building occupants' perception of thermal comfort can be influenced by a number of contextual factors, such as their demographic and anthropometric characteristics, behavioural patterns and cultural aspects. The objective of this work is to investigate the relationship between various contextual factors and the perception of thermal comfort in workplaces, by examining the gap between the current thermal comfort criteria and the actual requirements observed for different groups of occupants. The classic thermal comfort field research design i.e. simultaneous measurements of physical environmental parameters and questionnaire surveys, was implemented for two years in both centralised HVAC and mixed-mode office buildings located in Southern Brazil. Over 7500 questionnaires were completed by occupants of the buildings. Key variables including the participants' gender, age, body mass index, prior exposure to air-conditioning and building ventilation type were investigated in order to identify their association with thermal discomfort in the office workplace. Our results suggest that males, overweight occupants and those who are more frequently exposed to air-conditioning are more likely to express thermal discomfort due to feeling ‘warm’, compared to females, non-overweight occupants and those who were exposed to air-conditioning less frequently. In comparison, females, non-overweight occupants, air-conditioning light users, and occupants of centralised HVAC buildings were more likely to declare ‘cold’ discomfort. We also investigated how those variables were related to the width of thermal comfort zone. The analysis indicates that different groups of occupants require different comfort zones, suggesting that group differences should be considered when designing/operating spaces for diverse groups of occupants. [ABSTRACT FROM AUTHOR]

This study aims to better understand thermal comfort perception and related behavioural characteristics of school children. Statistical analyses were performed on the thermal comfort survey database consisting of 4866 responses collected from primary- and secondary school classrooms in Australia across two summer seasons. The students generally preferred ‘cooler-than-neutral’ sensations, with the preferred temperature being estimated to be 2–3 K below the neutrality predicted for adults under the same thermal environmental exposures. The students' 80% acceptability zone empirically derived from group mean thermal sensations, was significantly wider than the band of ±0.85 thermal sensation votes assumed in the PMV-PPD model. The school children indicated air-conditioning as their favoured thermoregulatory method, among many other adaptive options including windows, fans, blinds or clothing adjustments. The results indicated that those students already placed in air-conditioning classrooms were more likely to prefer air-conditioning for the maintenance of their comfort, compared to those accommodated in classrooms without air-conditioning. [ABSTRACT FROM AUTHOR]

This paper investigates air-conditioning (AC) usage patterns and adaptive comfort behaviors in a Chinese residential context. Field measurements were conducted in 43 homes in Tianjin from May 14 th to November 20 th in 2016. Indoor temperatures and AC on/off events were recorded. Occupants’ “right-here-right-now” thermal perception and adaptive behaviors were collected. 4,743 AC events and 1,697 online comfort questionnaires were collected. Average duration for AC cooling events in summer was 3.24 hrs per house and the average duration for AC heating events in winter was 0.96 hrs per house. Tianjin residents were less sensitive to indoor air temperature, compared to those in offices. The indoor temperatures corresponding to 80% thermal acceptability ranged from 21.0℃ to 27.3℃. We also derived statistical models to predict the likelihood of adaptive behaviors (i.e. turning on AC, turning on fans and opening windows or doors) with regard to outdoor air temperatures. [ABSTRACT FROM AUTHOR]

Typical commercial lease agreements in Australia stipulate 22.5 ± 1.5 °C in summer as the acceptable thermal condition that buildings have to meet, even though the overcooling incurs excessive and unnecessary energy use, gas emissions and financial expense. An argument that backs up this practice asserts that office workers' productivity and comfort will be jeopardised outside this temperature range. This paper investigated whether the office environments with a practical higher temperature setpoint can still be cognitively efficient and comfortable for office workers. In a controlled climate chamber, 26 office workers experienced the typical summer indoor temperature condition in Australia (22 °C) followed by the condition with a higher temperature setpoint (25 °C). In both conditions, subjects were required to fulfil Cambridge Brain Science (CBS) cognitive performance tests, NASA Task Load Index (NASA-TLX), and thermal comfort and air quality questionnaires. Meanwhile, participants' electroencephalogram (EEG) and heart rate (HR) were recorded under three different difficulty levels of Paced Auditory Serial Addition Tests (PASAT). Results showed that CBS test scores were not significantly affected by temperature; a higher temperature of 25 °C incurred a significantly reduced cognitive load for subjects, as has been observed by NASA-TLX, but probably due to the learning effect; the comparison between EEG and HR features during different temperatures did not show any significant difference. Participants' thermal comfort was not significantly jeopardized by the 3 °C temperature setback either. Results from this study favourably support a practical setback of temperature setpoints in Australian office buildings during summer. [ABSTRACT FROM AUTHOR]

Wind tunnel testing and thermal comfort simulations were conducted to explore the performance of a wind-tower in a typical, medium-density apartment building located in subtropical Sydney. The research design consisted of three phases; first, wind tunnel experiments measured pressure distributions over the surface of a four-storey apartment building model scaled at 1:100. Secondly, hourly indoor air velocities were predicted for the six warmest months in Sydney using the Typical Meteorological Year 2013. Finally, thermal comfort simulations evaluated the comfort cooling potential of the wind towers. Results indicate that, during Sydney's warm hours (≥23 °C), elevated air speeds resulting from the wind-tower improved in indoor comfort by 1725.8 degree hours (SET*) compared to the default design relying on through-window cross ventilation under the same conditions. [ABSTRACT FROM AUTHOR]

Direct load control (DLC) is a demand response strategy that allows a utility or an aggregator to cycle specific appliances of their customers on and off or implement thermostat setback during peak demand periods. In the present research, a methodology is proposed to optimise DLC air-conditioning algorithms in order to achieve optimum and robust thermal comfort and cognitive performance outcome for commercial building occupants using Taguchi method. Human subject experiments were carried out simulating DLC events with four control factors in a university lecture theatre. Results reveal that off cycle fraction and adapting temperature are the two most important control factors that affect both the variability and mean response of building occupants' thermal sensation; off cycle fraction is the only significant control factor that affects the robustness of occupants' cognitive performance while none of the four control factors has any significant impact on the mean performance scores. DLC algorithms with off cycle fraction not higher than 50% and adapting temperature lower than occupants' neutral temperature are recommended to achieve optimum and robust thermal comfort and cognitive performance outcome. Cycling period and building envelope thermal performance do not have any significant impact. DLC air-conditioning strategies can be widely implemented in commercial buildings with various thermal performance conditions as long as the off cycle fraction and adapting temperature are optimised. [ABSTRACT FROM AUTHOR]

• Pedestrians' thermal discomfort in daily commute is analogized to a capacitor. • The capacitor is fully charged when mean body temperature increment reaches 0.4°C. • A 0.7°C-minute decrement in mean skin temperature is needed for thermal respite. • A stretch of less severe heat exposure is more concerning than the hottest spots. Superimposition of global warming on urban heat islands is making outdoor cooling infrastructure critical to the maintenance of walkability of many cities. How to better arrange thermal respite (cooling infrastructure) to maximise pedestrians' thermal comfort is still unclear. In this study, the thermal discomfort accumulating during episodic exercise in outdoor heat was compared to the charging of a capacitor. Skin temperature and core temperature responses were collected from a sample of human participants (n=24) who were exposed to bouts of simulated urban heat stress, while exercising on an ergometer at an intensity corresponding to a brisk walk. Thermal respite (wind and/or shade) was provided to the participants to discharge accumulated heat load after they reached a specific threshold of thermal discomfort. We found that the thermal discomfort capacitor of most participants (75%) became fully charged ('pleasant' → 'intolerable') after a 0.4 °C increment in mean body temperature, and its discharge required a 0.7 °C degree-minute decrement in mean skin temperature. The comfort capacitor analogy provides an estimate of the intensity and duration of cooling respite required by pedestrians during brief exposures to overheated urban climates. This provides guidance on engineering interventions to ameliorate overheated urban microclimates. [ABSTRACT FROM AUTHOR]

The concept of non-territorial workplace has been adopted by a growing number of organisations. It is clear that the main driver for desk sharing practices is the tangible economic benefits guaranteed by reducing the amount of office space per person. However, the question of whether or not occupant comfort or productivity are compromised in the pursuit of space efficiency has never been investigated. This paper draws on a database from Australian building occupant survey to investigate how desk arrangements (whether or not one has a pre-allocated desk) can affect occupant satisfaction, self-reported productivity or health at workplaces. Our statistical model indicates a fall in occupant self-assessed productivity as spatial factors (such as the office layout allowing easiness of interaction with colleagues, the ability to adjust/personalise workspace, and the amount of storage space provided) perform below occupant expectations. Analysis of the results also show that the association of spatial factors with occupants' self-assessed productivity (quantified by odds ratios) was more pronounced among those in non-territorial workplaces, compared to those who are assigned with a pre-allocated desk. With respect to self-assessed health, the comfort of furnishing was identified as the strongest predictor for shared-desk users. Our findings suggest that these spatial factors, rather than the desk ownership itself, play a more significant role in the non-territorial work arrangement, affecting occupant attitude towards their building. [ABSTRACT FROM AUTHOR]

Direct load control (DLC) is a utility-sponsored demand response program which allows a utility to cycle specific appliances on and off during peak demand periods. Direct load control of air conditioners induces temperature cycles that might potentially compromise occupants' thermal comfort. In two separate experiments, 56 subjects' thermal comfort was closely examined during 6 DLC conditions and 2 control conditions simulated in a climate chamber, representing typical DLC-induced thermal environments in university lecture theatres. Results show that half of the DLC conditions were clearly accepted by subjects. Multilevel linear modelling of thermal sensation demonstrates that operative temperature, vapour pressure and the rate of temperature change are the three most important predictors during DLC events. Multilevel logistic regression indicates that in DLC conditions with lower adapting temperatures, thermal acceptability is significantly predicted by air speed and its interaction with operative temperature whereas in DLC conditions with higher adapting temperatures, by air speed, operative temperature and the rate of temperature change. Subjects' thermal comfort zone during DLC events is wider than predicted by Fanger's PMV/PPD model in that the former is more tolerant of cooler temperatures. Results from this study suggest that ASHRAE 55-2013 is overly conservative in defining the limits for temperature cycles, ramps and drifts. [ABSTRACT FROM AUTHOR]

India is witnessing unprecedented growth trends in building construction, particularly office spaces. Indian offices are designed to operate at 22.5 ± 1 °C all year round to meet the stringent “Class A” specifications outlined by international standards in the absence of an India-specific comfort standard. This paper proposes an India Model for Adaptive Comfort – IMAC – based on the field surveys administered in 16 buildings in three seasons and five cities, representative of five Indian climate zones. A total of 6330 responses were gathered from naturally ventilated, mixed mode and air-conditioned office buildings using instantaneous thermal comfort surveys. Occupants in naturally ventilated Indian offices were found to be more adaptive than the prevailing ASHRAE and EN models would suggest. According to the IMAC model, neutral temperature in naturally ventilated buildings varies from 19.6 to 28.5 °C for 30-day outdoor running mean air temperatures ranging from 12.5 to 31 °C. This is the first instance where a study proposes a single adaptive model for mixed mode buildings asserting its validity for both naturally ventilated and air-conditioned modes of operation in the building, with neutral temperature varying from 21.5 to 28.7 °C for 13–38.5 °C range of outdoor temperatures. For air-conditioned buildings, Fanger's static PMV model was found to consistently over-predict the sensation on the warmer side of the 7-point sensation scale. [ABSTRACT FROM AUTHOR]

In this paper we explore the notion of comfort expectations and ask the question whether they change as a result of long-term exposure to mild indoor climates. A comparative questionnaire survey was conducted in China where indoor thermal environments during winter in the northern region (with pervasive district heating) are much warmer than in the southern region (without district heating). Four subject groups were surveyed 1) subjects who had lived in the northern region of china with district heating all their life, 2) subjects who grew up in the southern region without district heating but as adults had moved to the north where district heating was pervasive, 3) subjects who had lived in the southern region of china without district heating all their life, and 4) subjects who grew up in the northern region with district heating but as adults had moved to the north where district heating was non-existent. Subjects who had lived their entire lives in the northern region with neutral-to-warm indoor climates had quite similar comfort perceptions and expressed the same levels of thermal acceptability as did those subjects whose life had been spent in the southern region, devoid of any district heating. Statistical analysis of the two sub-groups who migrated, north or south, indicated that it building occupants get accustomed to the thermally neutral lifestyle more easily and faster than do their counterparts who went from thermally neutral indoor climates of the north to the cold and uncomfortable indoor climates of the southern regions of China. [ABSTRACT FROM AUTHOR]

Domestic heating in the ‘Hot Summer–Cold Winter’ climatic region of China attracts research attention for it is predicted to dramatically increase building energy consumption and associated greenhouse gas emissions. Determining the optimum heating temperature set point is an essential prerequisite for research, technology and policy development in this topic. This paper reviews instrumental and subjective research about occupants' thermal comfort and behavior in this climatic region, and advances a hypothesis as to why residents in the ‘Hot Summer–Cold Winter’ region are able to accept a lower temperature (16.5 °C) in winter than are predicted by the heat balance model (PMV/PPD) and ASHRAE's adaptive comfort model. The paper concludes by recommending heating temperature set point (17–18 °C) based on a lumped-parameter four-node steady-state model and a prediction about the heating mode that will be utilized in this region. [ABSTRACT FROM AUTHOR]

While it is evident that thermal environment plays a significant role in human sleep quality, currently there remains a paucity of literature on the assessment of sleeping thermal environment. In this study, the two-node model has been adapted to evaluate sleeping thermal environments through two phases of work - modifications to the model's inputs and coefficients, and the conversion to a transient model. A calculation method for the model's key input intrinsic bedding insulation, I cl,bed , was proposed. The default heat transfer coefficients in the two-node model were replaced with the values corresponding to a supine human body. The two-node model's algorithm was adapted from its default, steady-state solution to a transient, time-series approach, to accommodate transients in both thermal environmental and physiological parameters through the course of the night. The modified two-node model was used to identify the optimum summer SET* sleep in a Sydney sleep survey database. Nocturnal mean skin temperatures predicted by the modified two-node model agree with the published physiological data in the literature. The upper limit of the Sydney summer bedroom SET* sleep for sleeping persons was 31 °C. In addition, the upper limit of summer operative temperatures was also determined for typical bedding systems. For instance, for the combination of short-sleeved sleepwear and Quilt1 (Warmth level 1), the upper limit of bedroom temperature was recommended to be 26.5 °C. Finally, the bedroom temperature control strategy for optimal sleep thermal comfort was predicted. • Two-node model was adapted to evaluate sleeping thermal environments. • An estimation method for the intrinsic bedding insulation (I cl,bed) was proposed. • The upper limit of summer SET*sleep was identified based on a sleep quality survey database. • Upper limits of summer bedroom operative temperatures for nine common bedding systems were obtained. [ABSTRACT FROM AUTHOR]

The experience of nature can bring various psychological benefits, including attention restoration, stress recovery, and mood improvement. Application of biophilic design principles to incorporate various forms of natural elements in workplaces can improve their occupants' productivity and psychological well-being. However, most of the research regarding restorative environments to date has been focused exclusively on their visual contents. The role of thermal perception in psychological restorative processes has largely been overlooked. This paper examines the restorative benefits of thermal pleasure experiences in the context workplace semi-outdoor environments. A pre-and-post-test experiment was conducted to compare the restorative effects of a workplace semi-outdoor space presenting two distinct thermal scenarios, one devoid of thermally adaptive opportunities, just direct sunlight exposure, and the other condition including the adaptive opportunity for subjects to select between direct sunlight or shade. The experiment used a multisensory virtual reality method to simulate the dynamic environmental conditions of an actual semi-outdoor space located in Melbourne Australia. Forty-two university students participated the experiment. The results showed a statistically significant association between thermal pleasure/thermal adaptive opportunity and restorative benefits. These findings suggest that thermal pleasure contributes to the restorative properties of workplace semi-outdoor environments, specifically in relation to attention restoration, stress recovery, and mood improvement. The study bridges the research fields of thermal comfort, virtual reality, and psychological restoration. The implementation of adaptive thermal comfort and alliesthesia concepts in semi-outdoor environmental design may add more than comfort improvements, but also broader psychological benefits that are relevant to an increasingly urbanised population. [Display omitted] • Thermal pleasure plays a critical role in the psychological restorative process. • Provision of shade as adaptive opportunity can improve restorative benefits. • Adaptive design strategies can be integrated into biophilic design framework. • Multisensory VR method was used for simulating semi-outdoor environments. [ABSTRACT FROM AUTHOR]

The seven-point thermal sensation scale provides a consistent measurement protocol widely applied in both field studies and lab experiments. Whilst thermal comfort studies have been carried out in diverse languages and cultures across the globe, there are suspicions among the research community whether the scale carries the same meaning when translated into different languages. This paper explores the question of semantics on the 7-point thermal sensation scale, focusing on identifying and quantifying linguistic bias introduced to the translation. Empirical data from multiple thermal comfort field survey campaigns administered in the Korean language are analysed and compared against reference data collected using the original English version of the ASHRAE scale (a subset of ASHRAE Global Thermal Comfort Database II from English-speaking countries). The analysis is focused on the question of whether survey respondents' interpretation of the scale systematically diverge from the assumptions underlying the original English version: i.e. (1) central three categories of the 7-point sensation scale being regarded as expressions of acceptable thermal comfort; (2) comfort being symmetrical around the optimum 'neutral' point; and (3) the widths of scale categories being consistent. Our analysis indicates that when translated into Korean the scale's semantics diverge significantly from the original English version. The implications of this discovery for previously published findings based on translated scales are also discussed. The paper calls for a more systematic investigation into linguistic dimensions of the scale to support a consistent and standardised guideline for the translation of thermal sensation scales from which compatible multilingual databases of thermal comfort can be developed. • Investigated semantic effects of thermal sensation descriptors. • Linguistic bias exists, affecting the interpretation of subjective warmth and associated analysis. • When translated, the internal dynamic and behaviour diverged from the original scale. • Previous findings based a meta-analysis may well be confounded with the language. • A standardised guideline for the translation of the scale is needed. [ABSTRACT FROM AUTHOR]

Indian residences are vulnerable to heat-driven discomfort amid the mounting prevalence of weather extremes, residential design and construction practices, and densifying urbanscapes. Therefore, it is vital to understand the thermal comfort characteristics of nationwide residences. This study proposes an adaptive thermal comfort model based on yearlong field surveys in eight cities located across five climate zones of India – the India Model for Adaptive Comfort - Residential (IMAC-R). The model prescribes the operative temperature bands for 80% and 90% thermal acceptability in correlation with the outdoor reference temperature, applicable to mixed-mode (MM) and naturally ventilated (NV) residences. More than 80% of the Indian residential occupants experienced a neutral thermal sensation in the indoor operative range of 16.3–35 °C in response to a 5.5–33 °C variation in the 30-day outdoor running mean temperature. Comparing the proposed model with the PMV model revealed that the latter underpredicts the thermal adaptivity of Indian occupants. The model was also compared against its predecessor – India Model for Adaptive Comfort for Commercial Buildings (IMAC MM and NV), along with relevant global and regional thermal comfort models. On average, the neutral temperature prescribed by IMAC-R was warmer than the temperatures prescribed by IMAC MM and NV by 2.9 °C and 2.1 °C, respectively; it was also warmer than the temperature prescribed by the recent ASHRAE-55 and EN 16798-1 models by 2 °C and 0.3 °C, respectively. IMAC-R reserves the prospect of addressing the thermal comfort needs of the national population while paving the way for long-term energy savings and climate action. • An adaptive model is proposed for mixed-mode and naturally ventilated residences across the Indian climates. • Indian residential occupants are more adaptive than as predicted by ASHRAE-55, EN 15251, and PMV models. • Fan/window operation and change in clothing insulation were the key adaptive responses. • Comfort modelling is explored in correlation with Universal Thermal Climate Index. [ABSTRACT FROM AUTHOR]

There have been much research focus on modelling various types of occupant thermal adaptive behaviour with an aim to improve the reliability of building energy performance simulation (BEPS) tools. However, most existing studies exploring occupant interaction with residential building systems limit their scope to a single, isolated behaviour (e.g. window opening only), which fails to consider that occupant reactions are determined by the interconnected effects of series of adaptive actions. This study aimed to develop a stochastic window operation model to address the interdependency between occupant's window and A/C operation. Longitudinal field observations were conducted in a sample of 41 Brisbane region households over a one-year period. The sample households' occupancy status, indoor environmental conditions, use of windows and air-conditioning (A/C) were continuously recorded. The cut-off temperature beyond which the probability of windows being open begins to decrease with an increase of the outdoor temperature, was found to be approx. 27 °C in both living and sleeping areas within the monitored households. This paper proposes a window operation model that captures diverse window opening patterns observed amongst the sample households, with a particular focus on the effect of A/C operation state on window opening and closing actions. The proposed model was tested by running 1000 simulations on a validation dataset. A good agreement observed between 1000 simulations and actual window use patterns indicates that the model can be applied to dynamic building energy performance and indoor environment simulations. • Cut-off temperature was found to be approx. 27 °C in both living and sleeping areas. • Effect of A/C operation state on window opening and closing actions was quantified. • The model creates diverse window patterns observed amongst the 41 sample households. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the gender differences in the occupants' perception on various aspects of indoor environmental quality (IEQ) by two lines of inquiry; Firstly, a comprehensive literature survey spanning the research areas of indoor air quality (IAQ), sick building syndrome (SBS), thermal comfort, lighting, and acoustics was conducted. Secondly, statistical analyses were performed on a large, predominantly North American Post-Occupancy Evaluation (POE) database (N = 38,257). Statistical analyses indicated that female occupants' satisfaction levels were consistently lower than male occupants for all fifteen IEQ factors (including thermal comfort, air quality, lighting, acoustics, office layout & furnishings, and cleanliness & maintenance) addressed in POE questionnaire, and the differences were statistically significant. Logistic regression analysis identified a significant association between female gender and dissatisfaction with individual IEQ factors. Those gender differences quantified by odds ratios (OR) were most pronounced for dissatisfaction with thermal environment, IAQ, and workspace cleanliness. The analyses produced consistent results, even after potential confounding factors such as age and work characteristics were controlled. [Copyright &y& Elsevier]

Office workers spend much of their working day sitting or standing still, which can have dramatic impacts on their health. The physical environment has long been regarded as influencing people's behaviour, including how much and how often they move. Developing a deeper understanding of relationships between specific spatial and environmental attributes and office workers' movement behaviour may inform the development of effective interventions to help people to move more whilst at work. In this study, the daily movement behaviour of 22 office workers was analysed using high resolution location data collected over 4 weeks and compared to their individual exposure to objectively measured spatial and IEQ attributes of their workplace. The results showed that increased visibility of colleagues had significant negative associations with several measures of daily movement behaviour, including the total area utilised each day (ß = −0.73, 95% CI: 1.29, −0.14, p < 0.05). The distance to office destinations such as kitchens and meeting rooms was found to be positively associated with the median duration of moving bouts (ß = 0.29, 95% CI: 0.11, 0.50, p < 0.01). Associations with IEQ exposures were primarily related to stationary behaviours, such as those between operative temperature and maximum stationary bout duration (ß = 149.15, 95% CI: 43.8, 260.0, p < 0.01). Although in most cases, the material impacts of the associations were small, the results suggest several promising avenues to pursue in the development of new design and policy-based interventions to help reduce stationary time and increase movement in the workplace. • High resolution location data collected over 4 weeks in 1,220m2 office workplace • Worker specific, objective daily measures of spatial attribute and IEQ exposures. • Visibility of co-workers was negatively associated with spatial utilisation • Operative temperature positively associated with duration of stationary bouts • New opportunities for developing design and policy-based workplace interventions [ABSTRACT FROM AUTHOR]

Assessment criteria for thermal comfort in residential buildings are often defined on the basis of the adaptive comfort model due to their typical operational characteristics – i.e. mixed-mode or naturally ventilation. However, recent field studies demonstrate that the current adaptive comfort model prescribed in the international standard does not necessarily provide appropriate comfort criteria for residential buildings, since its occupants may be less thermally sensitive due to enhanced adaptability and greater tolerance of temperature variation. This paper examined perception of thermal comfort and behavioural adaptation of residents in two cities on the east coast of Australia – Sydney and Brisbane. With an aim to develop a method of deriving acceptable temperature ranges for different climate characteristics, statistical analyses were performed on two sets of longitudinal field study data collected in the two study regions. The statistical analysis estimates the acceptable temperature range for the two cities at around 11 K, which is 4 K wider than that prescribed by the ASHRAE's adaptive comfort model. The results also indicate that the 80% acceptability range can shift according to the climate, with 1.5 K difference being observed between the two study regions. The findings of this study can help climate-responsive design of houses, hence allowing the design to more closely meet occupants' comfort needs. • Residential thermal comfort and behavioural adaptation in two cities are presented. • Acceptable temperature range was 4 K wider than the ASHRAE's adaptive comfort model. • Acceptable temperatures can shift according to the climate characteristics. • Findings of this study can help designing houses to meet occupants' comfort needs. [ABSTRACT FROM AUTHOR]

Green infrastructure has the potential to cool urban environments and reduce the health burden due to heatwaves. This study develops a new method to quantify the benefits of urban heat mitigation technologies on human heat balance and population mortality. The Heat Health Impact (HHI) method is based on the state-of-the-art, multi-parameter model, Universal Thermal Climate Index (UTCI). A proof-of-concept exercise applied the HHI method to Sydney, Australia (population = 5.7 million). All available weather stations (10) were selected for full spatial coverage of the Sydney region (12,367 km2), and average hourly UTCI was calculated from meteorological observations spanning the entire year 2017. In the baseline analysis, average daily UTCI values were calculated for each of the 10 observation sites, and then spatially interpolated across the entire Sydney region for Feb 9, 2017, a representative heatwave day for Sydney. Three different greening intervention scenarios were investigated, and daily average change in UTCI (ΔUTCI) was calculated under each by comparison with the baseline scenario; this ΔUTCI was named Urban Cooling Effect (UCE). We implemented a health impact assessment methodology to estimate the change in attributable mortality due to each greening scenario for the Sydney GMR population for the representative heatwave day. Urban greening infrastructure scenarios reduced daily average UTCI between −0.2 and −1.7 °C on the heatwave day, with the health impact assessment indicating heat attributable deaths reducing up to 11.7 per day across the Sydney GMR compared to the baseline scenario. Our results highlight the health benefits of greening infrastructure to cool urban environments. • A new method developed to quantify the benefits of urban greening on mortality. • Urban greening infrastructure reduced daily average UTCI between −0.2 and −1.7 °C. • Adaptation strategies reduced deaths up to 11.7 per day in Sydney during heatwave. [ABSTRACT FROM AUTHOR]

Occupants' thermal sensitivity influences comfort temperature, thermal comfort models, and building energy simulation. To date, a universal thermal sensitivity estimate (i.e. 0.5/°C), the so-called Griffiths Constant, has been widely used to estimate comfort temperatures. However, recent field evidence indicates that the constant is actually a variable that changes according to context. The objective of this study is to explore the impact of different thermal sensitivity values on adaptive comfort models using the ASHRAE Global Thermal Comfort Database II. The method followed five main steps: i) subset Database II to include entries with the requisite parameters; ii) estimate neutral temperature using the standard Griffiths method; iii) iterate step "ii" using different thermal sensitivity values; iv) derive adaptive comfort models for air-conditioned and naturally ventilated office buildings considering global and European datasets; v) compare resulting models. The results highlight that occupants' thermal sensitivity varies according to building ventilation type. Occupants in naturally ventilated offices were about half as sensitive to temperature changes as occupants in air-conditioned buildings. The most important outcome of this study is that thermal sensitivity and geographic region significantly affect the adaptive model relationship between outdoor temperature and indoor neutral temperature for occupants of naturally ventilated buildings; Occupants of European buildings are more sensitive to temperature changes than counterparts in other regions. The significance of this finding is that the adaptive model relationship forms the basis of the adaptive comfort standards, and so it has implications for both the design and operation of naturally ventilated and mixed-mode buildings. • Occupant's thermal sensitivity varies according to building ventilation type. • Thermal sensitivity affects the adaptive relationship between outdoor and indoor temperature. • Adaptive models are dependent on local contextual and cultural characteristics. [ABSTRACT FROM AUTHOR]