Search

Skin temperature detection thresholds have been used to measure human cold and warm sensitivity across the temperature continuum. They exhibit a sensory zone within which neither warm nor cold sensations prevail. This zone has been widely assumed to coincide with steady-state local skin temperatures between 32 and 34°C, but its underlying neurophysiology has been rarely investigated. In this study we employ two approaches to characterize the properties of sensory thermoneutrality, testing for each whether neutrality shifts along the temperature continuum depending on adaptation to a preceding thermal state. The focus is on local spots of skin on the palm. Ten participants (age: 30.3 ± 4.8 yr) underwent two experiments. Experiment 1 established the cold-to-warm inter-detection threshold range for the palm’s glabrous skin and its shift as a function of 3 starting skin temperatures (26, 31, or 36°C). For the same conditions, experiment 2 determined a thermally neutral zone centered around a thermally neutral point in which thermoreceptors’ activity is balanced. The zone was found to be narrow (~0.98 to ~1.33°C), moving with the starting skin temperature over the temperature span 27.5–34.9°C (Pearson r = 0.94; P < 0.001). It falls within the cold-to-warm inter-threshold range (~2.25 to ~2.47°C) but is only half as wide. These findings provide the first quantitative analysis of the local sensory thermoneutral zone in humans, indicating that it does not occur only within a specific range of steady-state skin temperatures (i.e., it shifts across the temperature continuum) and that it differs from the inter-detection threshold range both quantitatively and qualitatively. These findings provide insight into thermoreception neurophysiology. [ABSTRACT FROM AUTHOR]

The assignments of basal metabolic rates (BMR), basal cardiac output (BCO), and basal blood perfusion rates (BBPR) were compared in nine multi-compartment, whole-body thermoregulation models. The data are presented at three levels of detail: total body, specific body regions, and regional body tissue layers. Differences in the assignment of these quantities among the compared models increased with the level of detail, in the above order. The ranges of variability in the total body BMR was 6.5 % relative to the lowest value, with a mean of 84.3 ± 2 W, and in the BCO, it was 8 % with a mean of 4.70 ± 0.13 l/min. The least variability among the body regions is seen in the combined torso (shoulders, thorax, and abdomen: ±7.8 % BMR and ±5.9 % BBPR) and in the combined head (head, face, and neck ±9.9 % BMR and ±10.9 % BBPR), determined by the ratio of the standard deviation to the mean. Much more variability is apparent in the extremities with the most showing in the BMR of the feet (±117 %), followed by the BBPR in the arms (±61.3 %). In the tissue layers, most of the bone layers were assigned zero BMR and BBPR, except in the shoulders and in the extremities that were assigned non-zero values in a number of models. The next lowest values were assigned to the fat layers, with occasional zero values. Skin basal values were invariably non-zero but involved very low values in certain models, e.g., BBPR in the feet and the hands. Muscle layers were invariably assigned high values with the highest found in the thorax, abdomen, and legs. The brain, lung, and viscera layers were assigned the highest of all values of both basal quantities with those of the brain layers showing rather tight ranges of variability in both basal quantities. Average basal values of the 'time-seasoned' models presented in this study could be useful as a first step in future modeling efforts subject to appropriate adjustment of values to conform to most recently available and reliable data. [ABSTRACT FROM AUTHOR]

An office equipped with personal footwarmers was maintained at cooler-than-normal indoor temperatures in the winter, producing great energy savings. The occupants’ thermal comfort was not affected. The footwarmers provide individual heating control over a segment of the body that most strongly influences comfort perception when one is cool overall. If cooler ambient indoor temperatures could be made comfortable, savings in central heating energy would be possible. During a six-month winter period in Berkeley California, knowledge workers with low-energy footwarmers experienced a lowering of room heating set point from 21.1 °C (70 °F) to 18.9 °C (66 °F). Surveys showed equal thermal comfort in the original ‘higher heating setpoint no-footwarmer’ condition and the ‘lower heating set point plus occupant-controllable footwarmer’ condition. Heating energy was closely monitored throughout. It dropped 38–75% depending on the setpoint reduction and outdoor conditions. The added plug load energy from the low-energy footwarmers was much less than the central heating energy saved by lowering the heating set point (3–21 W vs 500–700 W average power per occupant during occupied hours). A few subjects had ergonomic issues with the particular footwarmers used, so usage was not universal. Additional foot- and leg-warmer design options would help. [ABSTRACT FROM AUTHOR]

There is great energy-saving potential in reducing variable air volume box minimum airflow set-points to about 10% of maximum. Typical savings are on the order of 10%–30% of total HVAC energy, remarkable for an inexpensive controls set-point change that properly maintains outside air ventilation. However, there has long been concern whether comfort and room air mixing are maintained under low flows through diffusers, and this concern has prompted variable air volume minima to be typically set at 20%–50% of maximum. RP 1515 evaluated occupants’ thermal comfort and air quality satisfaction in operating buildings under both conventional and reduced minimum variable air volume flow set-points, and measured the air diffusion performance index and air change effectiveness for typical diffuser types in the laboratory. The hypotheses were that lowered flow operation would not significantly reduce comfort or air quality and that HVAC energy savings would be substantial. The hypotheses were almost entirely confirmed for both warm and cool seasons. But beyond this, the reduction of excess airflow during low-load periods caused occupants’ cold discomfort in the warm season to be halved, a surprising improvement. It appears that today's widespread overcooling of buildings can be corrected without risk of discomfort by lowering conventional variable air volume minimum flow set-points. [ABSTRACT FROM PUBLISHER]

Subjects exposed to uniform environments were polled for their local and overall (whole-body) thermal sensation and comfort. Sensation and comfort for local body parts vary greatly. In cool environments, hands and feet feel colder than other body parts. The head, insensitive to cold but sensitive to warm, feels warmer than the rest of the body in warm environments. Overall sensation and comfort follow the warmest local sensation (head) in warm environments and the coldest (hands and feet) in cool environments. Subjects evaluate neutral conditions as “comfortable”, never “very comfortable”, and overshoot of sensation and comfort during whole-body step-changes is small. [Copyright &y& Elsevier]

Abstract: Subjects were exposed to sequences of partial-body cooling and warming over a period of 3h. Skin temperatures, core temperature, thermal sensation, and comfort responses were collected for 19 local body parts, and for the whole body. This paper relates local thermal sensations and comfort to skin and core temperatures, and examines how the thermal sensation and comfort perceived for individual body parts affect thermal sensation and comfort perceived for the whole body. Overshoot in sensation and comfort is stronger when local body parts are cooled or warmed than when the whole body experiences a step-change. [Copyright &y& Elsevier]

Analyzes the effect of future development in Toronto's Central Area on street-level conditions of sun, wind, and thermal comfort. Shadowing produced by downtown buildings; Procedures and standards for preserving sunlight on Toronto's downtown sidewalks and open spaces; Effects of buildings on wind conditions at street level; Combined effects of sun and wind conditions on pedestrian comfort.

The ability to inexpensively monitor indoor air speed and direction on a continuous basis would transform the control of environmental quality and energy use in buildings. Air motion transports energy, ventilation air, and pollutants around building interiors and their occupants, and measured feedback about it could be used in numerous ways to improve building operation. However indoor air movement is rarely monitored because of the expense and fragility of sensors. This paper describes a unique anemometer developed by the authors, that measures 3-dimensional air velocity for indoor environmental applications, leveraging new microelectromechanical systems (MEMS) technology for ultrasonic range-finding. The anemometer uses a tetrahedral arrangement of four transceivers, the smallest number able to capture a 3-dimensional flow, that provides greater measurement redundancy than in existing anemometry. We describe the theory, hardware, and software of the anemometer, including algorithms that detect and eliminate shielding errors caused by the wakes from anemometer support struts. The anemometer has a resolution and starting threshold of 0.01 m/s, an absolute air speed error of 0.05 m/s at a given orientation with minimal filtering, 3.1° angle- and 0.11 m/s velocity errors over 360° azimuthal rotation, and 3.5° angle- and 0.07 m/s velocity errors over 135° vertical declination. It includes radio connection to internet and is able to operate standalone for multiple years on a standard battery. The anemometer also measures temperature and has a compass and tilt sensor so that flow direction is globally referenced regardless of anemometer orientation. The retail cost of parts is $100 USD, and all parts snap together for ease of assembly. Image, graphical abstract [ABSTRACT FROM AUTHOR]

[Display omitted] • Thermostatic air-conditioning control can discomfort occupants by overcooling spaces. • Machine vision + infrared thermography measures face, nose, and hand temperatures. • Human skin temperature distribution predicts cool/neutral/warm thermal sensation. • Infrared biometric sensor-controller targets neutral-to-slightly warm sensation. • Office-building trial demonstrated comfort improvement and 42% cooling-load reduction. To improve occupant comfort and save energy in buildings, we have developed a closed-loop air conditioning (AC) sensor-controller that predicts occupant thermal sensation from the thermographic measurement of skin temperature distribution, then uses this information to reduce overcooling (cooling-energy overuse that discomforts occupants) by regulating AC output. Taking measures to protect privacy, it combines thermal-infrared (TIR) and color (visible spectrum) cameras with machine vision to measure the skin-surface temperature profile. Since the human thermoregulation system uses skin blood flow to maintain thermoneutrality, the distribution of skin temperature can be used to predict warm, neutral, and cool thermal states. We conducted a series of human-subject thermal-sensation trials in cold-to-hot environments, measuring skin temperatures and recording thermal sensation votes. We then trained random-forest classification machine-learning models (classifiers) to estimate thermal sensation from skin temperatures or skin-temperature differences. The estimated thermal sensation was input to a proportional integral (PI) control algorithm for the AC, targeting a sensation level between neutral and warm. Our sensor-controller includes a sensor assembly, server software, and client software. The server software orients the cameras and transmits images to the client software, which in turn assesses occupant skin temperature distribution, estimates occupant thermal sensation, and controls AC operation. A demonstration conducted in a conference room in an office building near Houston, TX showed that our system reduced overcooling, decreasing AC load by 42% when the room was occupied while improving occupant comfort (fraction of "comfortable" votes) by 15 percentage points. [ABSTRACT FROM AUTHOR]

In a field study conducted in office settings in Sydney, Australia, background survey and right‐here‐right‐now thermal comfort questionnaires were collected from a sample of office workers. Indoor environmental observations, including air temperature, mean radiant temperature, air velocity, and relative humidity, were also recorded and matched with each questionnaire according to the time and location. During exploratory data analyses, we observed that female subjects aged over 40 and 50 or younger registered significantly warmer sensations than other subjects, male and female, from other age ranges. To further explore this phenomenon, the sample of building occupants was classified into two groups—women of perimenopausal age (over 40 and 50 or younger) while the remaining respondents served as a reference group for comparison. Women in the perimenopausal age range demonstrated an increased perception of warmth (p < 0.01) and expressed thermal dissatisfaction more frequently (p < 0.01) than the reference group respondents who were exposed to the same indoor environmental conditions. Furthermore, women of perimenopausal age also expressed preference for cooler thermal environments, that is, lower air temperature (p < 0.01) and greater air movement (p<0.01) than the reference group, and their thermal neutrality (ie, the room temperature corresponding to a neutral thermal sensation) was approximately 2°C cooler than that of the reference group (20.7°C vs 22.4°C). A potential physiological explanation for the distinct thermal perception of women aged over 40 and 50 or younger observed in this study could stem from menopausal symptoms—the presence of hot flushes and dysregulation of the thermoregulatory system. [ABSTRACT FROM AUTHOR]

Building occupants are a rich source of information about indoor environmental quality and its effect on comfort and productivity. The Center for the Built Environment has developed a Web-based survey and accompanying online reporting tools to quickly and inexpensively gather, process and present this information. The core questions assess occupant satisfaction with the following IEQ areas: office layout, office furnishings, thermal comfort, indoor air quality, lighting, acoustics, and building cleanliness and maintenance. The survey can be used to assess the performance of a building, identify areas needing improvement, and provide useful feedback to designers and operators about specific aspects of building design features and operating strategies. The survey has been extensively tested and refined and has been conducted in more than 70 buildings, creating a rapidly growing database of standardized survey data that is used for benchmarking. We present three case studies that demonstrate different applications of the survey: a pre/post analysis of occupants moving to a new building, a survey used in conjunction with physical measurements to determine how environmental factors affect occupants' perceived comfort and productivity levels, and a benchmarking example of using the survey to establish how new buildings are meeting a client's design objectives. In addition to its use in benchmarking a building's performance against other buildings, the CBE survey can be used as a diagnostic tool to identify specific problems and their sources. Whenever a respondent indicates dissatisfaction with an aspect of building performance, a branching page follows with more detailed questions about the nature of the problem. This systematically collected information provides a good resource for solving indoor environmental problems in the building. By repeating the survey after a problem has been corrected it is also possible to assess the effectiveness of the solution. [ABSTRACT FROM AUTHOR]

1. Human subjects were exposed to partial- and whole-body heating and cooling in a controlled environmental chamber to quantify physiological and subjective responses to thermal asymmetries and transients.2. Skin temperatures, core temperature, thermal sensation, and comfort responses were collected for 19 local body parts and for the whole body.3. Core temperature increased in response to skin cooling and decreased in response to skin heating.4. Hand and finger temperatures fluctuated significantly when the body was near a neutral thermal state.5. When using a computer mouse in a cool environment, the skin temperature of the hand using the mouse was observed to be 2–3°C lower than the unencumbered hand. [Copyright &y& Elsevier]

• Presented the variation in metabolic rate of Chinese subjects in different activities considering gender and age factors. • Women have lower metabolic rates than men in various activities and ages, emphasizing the importance of gender in studying metabolic rate and thermal comfort. • No age-related declines in metabolic heat production during lower activities, but an increase in production rates with age. • Differences compared to international standards suggest the need for potential modifications when applying them to the Chinese population. Metabolic rate is an essential factor in determining human thermal comfort. Existing metabolic rates for common activities in the current standards are based on mean adult values and do not include values for the middle-aged and the elderly. This study examines the metabolic rate of 151 Chinese male and female subjects aged 20 ∼ 69 during eighteen activities (reclining, 7 types of office work including seated and standing, 5 types of housework, and 5 walking speeds) using an indirect calorimeter in lab studies. The results show that women exhibited lower metabolic heat production rates (6–9% for sedentary and standing activities, 9–13% for household activities, and 4–9% for walking activities) than men across all activities, regardless of age. No age-related declines in metabolic heat production during lower activities (reclining, sedentary, standing, and household). Rather, metabolic heat production rates increased at a rate of 5–7 W/m2 per decade with age, which is contrary to popular beliefs. Women demonstrated a distinct pattern of changes compared to men, with significant declines observed in sitting and standing activities, at a rate of 2–3 W/m2 per decade. The ISO and ASHRAE standards tended to overestimate the metabolic rate for standing position activities and significantly underestimate the metabolic rate during walking. Some simple household activities, such as folding cloth, wiping windows, and vacuuming, had a moderate metabolic rate level, significantly higher than standing quiet. These findings could inform the development of interventions to promote healthy ageing and the design of more effective strategies for managing thermal comfort in different populations. It is suggested that the metabolic rate reference table or prediction method in international standards needs modification when applied to the Chinese population. [ABSTRACT FROM AUTHOR]

Ceiling-fan-integrated air-conditioning (CFIAC) is a concept in which terminal supply ducts and diffusers are replaced by vents/nozzles that jet supply air into the vicinity of ceiling fans to be mixed and distributed within the room. CFIAC distributes the supply air within the room and convectively cools the occupants. This could allow raised thermostat setpoints and reduced energy for the air-conditioning system's supply fan and compressor. Previous work on CFIAC shows that the air temperature in the occupied zone is spatially uniform, but the air speed is not. This paper evaluates the thermal comfort performance of a CFIAC system under various ambient temperatures and fan operation modes. Human subject experiments and thermal manikin tests were conducted to characterize how subjects evaluate the thermal comfort performance across the room's floorplate, and how CFIAC affects human body heat transfer. Despite the spatial variation in air speed across the floorplate, CFIAC created uniform thermal comfort perceptions. Comfort at 28°C was similar to that of 26°C for the overhead supply neutral reference condition. Human subjects preferred having the increased air movement over that of the reference condition. The paper evaluates thermal comfort indexes appropriate for evaluating and designing CFIAC. [ABSTRACT FROM AUTHOR]

• An upward-directed ceiling fan reduces air temperature in the occupied zone by 2–6 ℃. • The radiant surface temperature can be raised by 2 ℃ while maintain thermal comfort when using fan. • The radiation heat transfer coefficient decreases by 25% at an acoustical panel coverage rate of 63%. • An upward-directed ceiling fan doubles the total heat transfer coefficient of the system without the fan. We evaluate the heat transfer from radiant ceilings that have suspended acoustical panels present for noise reduction. An upward-directed ceiling fan is added to offset the reduction of heat exchange due to the acoustical panels. We systematically simulate the indoor thermal environment and the changes to heat transfer coefficients caused by the interaction between radiant ceiling panels, acoustical panels, and ceiling fan under four influencing factors: (1) coverage ratio of acoustical panels, (2) fan rotational speed, (3) radiation panel temperature and (4) room height. The simulation method is validated with experimental data. Numerical results show that the augmented air speed increases convective and total heat transfer for radiant panel. Simulated temperature non-uniformity, air and operative temperature in the occupied part of the room is reduced with increased fan speed, and with decreased acoustical panel coverage ratio. The PMV increased with increased acoustical panel coverage ratio and radiant surface temperature, and also with reduced fan speed. When using fans, the radiant surface temperature can be raised 2 ℃ while maintaining equivalent thermal comfort, allowing higher water supply temperatures. The radiation heat transfer coefficient of the bare ceiling is decreased 25% by adding 63% acoustical panel coverage. The total heat transfer coefficient of radiant ceiling increases with fan speed up to 106.2% over a no-fan base case, and decreases with increased acoustical panel coverage ratio. The study indicates that an upward-directed ceiling fan is a worthwhile method to enable raised radiant surface temperatures, save cooling energy, and reduce surface condensation risk. [ABSTRACT FROM AUTHOR]

Highlights • A framework to learn occupant interactions from ambient sensing technologies is proposed. • Several machine learning algorithms are tested and the one that outperforms others is selected. • The framework selects proper the technologies and averaging windows. • 221 employees of federal agencies participated in this study. • Using random forest algorithm an accuracy of 86.72% to predict interactions was obtained. Abstract Having access to real-time information on building occupants' state of interactions enables optimization of building systems for improved energy efficiency, well-being and productivity of the occupants. In this paper, we propose a framework to learn occupant interactions from ambient sensing technologies (e.g., sensing of variables such as sound (dB), CO2 (ppm), light intensity (lux), dry-bulb temperature (°C), relative humidity (RH%), pressure (mbar)) from both stationary and wearable devices and select the technologies and averaging windows which contain the required information for learning. In this framework, several supervised machine learning algorithms are tested on the labeled datasets and the algorithm which outperforms others is selected. Two types of sensing devices were utilized for analyses: wearable devices worn around the neck by the test subjects, and a network of stationary devices located in the test subjects' working indoor spaces. 221 employees of federal agencies housed in facilities managed by the US. General Services Administration in the mid-Atlantic and Southern states participated in this study, answering questions about their current task every hour. Overall accuracies were observed of 86.72% for wearable and stationary devices, 81.25% for only wearable-only, and 85.16% for stationary-only for prediction of the mixed multi-label classification via Random Forests algorithm. The high prediction allows for identifying subjects' tasks when training labels are not available. Predicting occupants' interactions as a main indicator of occupants' behavior have significant implications for the energy efficiency of building systems (up to 20% savings). [ABSTRACT FROM AUTHOR]

Human occupants are an important source of microbes in indoor environments. In this study, we used DNA sequencing of filter samples to assess the fungal and bacterial composition of air in an environmental chamber under different levels of occupancy, activity, and exposed or covered carpeting. In this office-like, mechanically ventilated environment, results showed a strong influence of outdoor-derived particles, with the indoor microbial composition tracking that of outdoor air for the 2-hour sampling periods. The number of occupants and their activity played a significant but smaller role influencing the composition of indoor bioaerosols. Human-associated taxa were observed but were not particularly abundant, except in the case of one fungus that appeared to be transported into the chamber on the clothing of a study participant. Overall, this study revealed a smaller signature of human body-associated taxa than had been expected based on recent studies of indoor microbiomes, suggesting that occupants may not exert a strong influence on bioaerosol microbial composition in a space that, like many offices, is well ventilated with air that is moderately filtered and moderately occupied. [ABSTRACT FROM AUTHOR]

Human metabolic rate is a fundamental and essential aspect of thermal comfort, and gender differences in metabolic rate may underlie gender differences in comfort. This study explores gender differences in physiological and subjective responses to a wide range of cold to hot temperatures. Forty healthy college students (20 females and 20 males) participated in the experiments. Subjects were sedentary, wearing 0.6 clo, staying at 26 °C for 30 min, then exposed to either at cool (14, 16, 18, 20 °C), neutral (24, 26 °C), or warm (28, 30, 32, and 34 °C) temperatures for 90 min. Both subjective questionnaires (thermal sensation, thermal comfort, thermal acceptability) and physiological measurements (metabolic rate, skin temperature, skin blood flow, and skin wettedness) were collected during the exposures. Females tend to have lower metabolic rates than males at all temperatures, although significant differences were only found at 14, 16, and 18 °C. Females tend to be cooler and less comfortable than males at cool temperatures, which could be explained by the lower metabolic rates and lower skin temperatures in females. Males tend to be warmer and less comfortable at warm temperatures, which could be explained by higher metabolic rates and higher skin wettedness in males. No significant gender differences in subjective or physiological responses were found at neutral conditions. [ABSTRACT FROM AUTHOR]

• 98 seated persons in a lab experiment with thermal stratification up to 8.4 °C/m. • Temperature gradient has small impact on whole-body acceptability at 8.4 °C/m. • We developed a model to estimate the predicted percentage dissatisfied (PPD ∇T). • Thermal sensation and vertical temperature gradient affect PPD ∇T. • 5 °C/m between head and feet is acceptable for whole-body thermal neutrality. A vertical thermally stratified environment provides opportunities for improved ventilation effectiveness and energy efficiency, but vertical temperature gradient can also cause local thermal discomfort. ASHRAE 55 and ISO 7730 prescribe a 3 °C/m limit between head and feet for seated persons. However, an increasing amount of evidence suggests that this limit is too restrictive. To revisit how vertical temperature gradient affects local thermal comfort, we conducted laboratory tests with four nominal vertical temperature gradients (0.4, 2.9, 5.9, and 8.4 °C/m). Ninety-eight seated college-age students participated in a blind within-subject experiment. Cold-feet discomfort is more frequently rated than warm-head discomfort with increasing temperature gradients. By using logistic regression modeling, we show that the whole-body dissatisfaction increases only slightly (<10%) with vertical temperature gradient, even up to 8.4 °C/m. Sex does not significantly affect the results except at 8.4 °C/m. Acceptable vertical temperature gradient changes with thermal sensation votes. The results suggest that the vertical temperature gradient could be increased to 5 °C/m between head and feet when the subject is thermally neutral. Image, graphical abstract [ABSTRACT FROM AUTHOR]

• Chamber study on preferred temperature with and without air movement during moderate exercise. • Preferred temperature decreases as activity level increases. • People prefer air movement over cold ambient temperatures during exercise. • PMV model is not suitable to predict thermal comfort for people during exercise. • Sports facilities shall consider providing personal controlled air movement with warmer setpoint temperature to save energy while maintaining thermal comfort. During exercise, comfort requirements are different because of the elevated metabolic heat production. It is essential to know the preferable thermal environment to give environmental design suggestions to sports facilities. Experimental studies on preferred temperature were conducted on 20 healthy human subjects walking on a treadmill at 4, 5, and 6 km/h, with and without self-controlled air movement. Physiological responses (metabolic rate, skin temperature, skin wettedness, and heart rate) were monitored, while their subjective responses were collected by questionnaires. Metabolic rates were 3.0, 3.5, and 4.5 met for 4, 5, and 6 km/h walking. Preferred temperatures were significantly lower without fan (23.3, 22.8, and 22.1°C without fan vs. 24.9, 24.1, and 23.6°C with fan), and all subjects were satisfied with their preferred thermal environment. PMV model was found to overestimate the cooling requirements for exercising people. Our results indicate that human in exercise does not necessarily want neutral temperature but want somewhat warm sensations, with lower temperature, higher skin wettedness, and higher core temperature. Overall, the results suggest that design temperature shall be 22–24°C without air movement, and 24–26°C with personally controlled air movement. [ABSTRACT FROM AUTHOR]

Naturally ventilated buildings have been found to be comfortable over a wider range of indoor temperatures than in air-conditioned buildings, while using less energy. The mechanisms underlying this are not well understood. Through a longitudinal field study of a naturally ventilated office in Alameda, CA, we obtained insights into how occupants exercise various adaptive control opportunities to meet their comfort needs in the absence of a mechanical HVAC system. Continuous measurements were made of adaptive behaviors such as window state, ceiling fan usage, heater usage, and indoor and outdoor climate (dry-bulb air temperature, relative humidity, CO 2 , outdoor temperature). Over 1400 thermal comfort survey responses were collected, which showed that the building provided acceptable thermal conditions for 98% of the survey period, covering an indoor temperature range of 16–28°C. Occupants wore clothing between 0.5 and 0.6 clo in summer, and 0.7–0.8 in winter. Occupants opened windows when the outdoor temperature was above 15°C, with window opening often occurring at the occupant's arrival and proportional to outdoor temperature. Fan use was best explained by indoor temperature, typically being turned on during summer at indoor temperatures above 25°C. Heaters were turned on in winter more than an hour after arrival and commencement of sedentary activity. With these adaptive control behaviors, occupants were thermally neutral and satisfied from 18 to 27°C. Their satisfaction exceeded that predicted by ASHRAE Standard 55 or PMV-based ISO standards. Overall, our findings provide empirical support for adopting adaptive comfort model in office buildings. [ABSTRACT FROM AUTHOR]