Use of mean skin temperature in evaluation of individual thermal comfort for a person in a sleeping posture under steady thermal environment

Nude men were exposed to a range of ambient temperatures and were brought to a condition of thermal comfort by adjustment of the incident radiation. The mean skin temperature associated with comfort was found to be different for each combination of ambient temperature and incident radiation. It was evident that mean skin temperature, per se, was not a dependable criterion of thermal comfort.

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Evaluation of calculation methods of mean skin temperature for use in thermal comfort study

Building and Environment ◽

10.1016/j.buildenv.2010.08.011 ◽

2011 ◽

Vol 46 (2) ◽

pp. 478-488 ◽

Cited By ~ 100

Author(s):

Weiwei Liu ◽

Zhiwei Lian ◽

Qihong Deng ◽

Yuanmou Liu

Keyword(s):

Thermal Comfort ◽

Skin Temperature ◽

Mean Skin Temperature ◽

Calculation Methods

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The effects of firefighting boots and personal protective equipment load on foot thermal comfort

Textile Research Journal ◽

10.1177/00405175211026538 ◽

2021 ◽

pp. 004051752110265

Author(s):

Miao Tian ◽

Xianghui Zhang ◽

Xumei Tang

Keyword(s):

Thermal Comfort ◽

Skin Temperature ◽

Personal Protective Equipment ◽

Thermal Environment ◽

Thermal Sensation ◽

Whole Body ◽

Protective Equipment ◽

Human Foot ◽

Physiological Variables ◽

Psychological Scales

Maintaining foot comfort is important as it influences the overall comfort of the human body. Shoe microclimate and foot skin temperature have been suggested to contribute to the thermal sensation of the foot. Considering the thermal environment and personal protective equipment (PPE) used for structural and proximity firefighting, climatic chamber tests with 13 male participants were conducted during standing and walking. Four test conditions – unloaded with training shoes, loaded with training shoes, unloaded with firefighting boots, and loaded with firefighting boots – were designed to investigate the effects of firefighting boots and PPE load on the thermal comfort of the human foot. Physiological variables of in-shoe and foot skin temperature at the whole and local regions of the foot were measured and subjective responses were gathered using psychological scales. The results showed that wearing firefighting boots may elevate the thermal sensation of wearers. The PPE load increased the in-shoe and foot skin temperature as well as subjective ratings. Subjective sensations of the foot were strongly correlated with in-shoe and skin temperature in the plantar regions. Correlation analysis of thermal sensation at the whole and local foot regions indicated that the sensation at the forefoot was closest to the whole foot, followed by the midfoot and heel. The findings address the relationship of physiological and subjective variables as well as the thermal sensation of whole and local foot regions, which can be considered for footwear design and thermal comfort prediction of the foot and whole body.

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Effect of Glove Liners on Sweat Rate, Comfort, and Psychomotor Task Performance

Textile Research Journal ◽

10.1177/004051758805800307 ◽

1988 ◽

Vol 58 (3) ◽

pp. 166-173 ◽

Cited By ~ 9

Author(s):

Donna H. Branson ◽

Lynda Abusamra ◽

Carolyn Hoener ◽

Sandra Rice

Keyword(s):

Thermal Comfort ◽

Skin Temperature ◽

Task Performance ◽

Individual Variation ◽

Thermal Environment ◽

Sweat Rate ◽

Manual Dexterity ◽

Thermal Discomfort ◽

Protective Gloves ◽

Perceived Temperature

Military subjects participated in a study to evaluate four glove liners worn beneath chemical protective gloves, with regard to sweating of the hands, manual dexterity performance, and perceived comfort in a moderate thermal environment. Although there was a trend for subjects wearing the standard Army liner to experience the lowest sweat rate, the liner effect was not significant due to individual variation. No liner differences were found for manual dexterity performance, hand skin temperature, perceived temperature, and thermal comfort. Differences by liner were found for tactile descriptors used to assess liner comfort. Skin temperature, perceived temperature, and perceived thermal discomfort increased over the duration of the two-hour test, regardless of the liner worn.

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Exoskeletons and Exosuits Could Benefit from Mode-Switching Body Interfaces That Loosen/Tighten to Improve Thermal Comfort

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph182413115 ◽

2021 ◽

Vol 18 (24) ◽

pp. 13115

Author(s):

Laura J. Elstub ◽

Shimra J. Fine ◽

Karl E. Zelik

Keyword(s):

Physical Activity ◽

Thermal Comfort ◽

Skin Temperature ◽

Thermal Environment ◽

Case Series ◽

The Body ◽

Mode Switching ◽

Single Subject ◽

Single Subject Design ◽

Case Series Study

Exoskeletons and exosuits (exos) are wearable devices that physically assist movement. User comfort is critically important for societal adoption of exos. Thermal comfort (a person’s satisfaction with their thermal environment) represents a key design challenge. Exos must physically attach/interface to the body to apply forces, and these interfaces inevitably trap some heat. It is envisioned that thermal comfort could be improved by designing mode-switching exo interfaces that temporarily loosen around a body segment when assistive forces are not being applied. To inform exo design, a case series study (N = 4) based on single-subject design principles was performed. Our objective was to assess individual responses to skin temperature and thermal comfort during physical activity with a Loose leg-sleeve interface compared with a Form-Fitting one, and immediately after a Form-Fitting sleeve switched to Loose. Skin under the Loose sleeve was 2–3 °C (4–6 °F) cooler after 25 min of physical activity, and two of four participants reported the Loose sleeve improved their thermal comfort. After completion of the physical activity, the Form-Fitting sleeve was loosened, causing a 2–4 °C (3–8 °F) drop in skin temperature underneath for all participants, and two participants to report slightly improved thermal comfort. These findings confirmed that an exo that can quickly loosen its interface when assistance is not required—and re-tighten when it is— has the potential to enhance thermal comfort for some individuals and environments. More broadly, this study demonstrates that mode-switching mechanisms in exos can do more than adjust physical assistance: they can also exploit thermodynamics and facilitate thermoregulation in a way that enhances comfort for exo users.

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Evaluating the Connection between Thermal Comfort and Productivity in Buildings: A Systematic Literature Review

Buildings ◽

10.3390/buildings11060244 ◽

2021 ◽

Vol 11 (6) ◽

pp. 244

Author(s):

Ana Maria Bueno ◽

Antonio Augusto de Paula Xavier ◽

Evandro Eduardo Broday

Keyword(s):

Literature Review ◽

Thermal Comfort ◽

Systematic Literature Review ◽

Thermal Environment ◽

Final Analysis ◽

Personal Factors ◽

Exclusion Criteria ◽

Environment Variables ◽

Main Factors ◽

Combination Of Methods

The thermal environment is one of the main factors that influence thermal comfort and, consequently, the productivity of occupants inside buildings. Throughout the years, research has described the connection between thermal comfort and productivity. Mathematical models have been established in the attempt to predict changes in productivity according to thermal variations in the environment. Some of these models have failed for a number of reasons, including the understanding of the effect that several environment variables have had on performance. From this context, a systematic literature review was carried out with the aim of verifying the connection between thermal comfort and productivity and the combinations of different thermal and personal factors that can have an effect on productivity. A hundred and twenty-eight articles were found which show a connection between productivity and some thermal comfort variables. By means of specific inclusion and exclusion criteria, 60 articles were selected for a final analysis. The main conclusions found in this study were: (i) the vast majority of research uses subjective measures and/or a combination of methods to evaluate productivity; (ii) performance/productivity can be attained within an ampler temperature range; (iii) few studies present ways of calculating productivity.

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Development of a Deep Neural Network Model for Estimating Joint Location of Occupant Indoor Activities for Providing Thermal Comfort

Energies ◽

10.3390/en14030696 ◽

2021 ◽

Vol 14 (3) ◽

pp. 696

Author(s):

Eun Ji Choi ◽

Jin Woo Moon ◽

Ji-hoon Han ◽

Yongseok Yoo

Keyword(s):

Neural Network ◽

Thermal Comfort ◽

Deep Neural Network ◽

Mean Squared Error ◽

Thermal Environment ◽

The Body ◽

Estimation Accuracy ◽

Accurate Estimation ◽

Body Parts ◽

Joint Location

The type of occupant activities is a significantly important factor to determine indoor thermal comfort; thus, an accurate method to estimate occupant activity needs to be developed. The purpose of this study was to develop a deep neural network (DNN) model for estimating the joint location of diverse human activities, which will be used to provide a comfortable thermal environment. The DNN model was trained with images to estimate 14 joints of a person performing 10 common indoor activities. The DNN contained numerous shortcut connections for efficient training and had two stages of sequential and parallel layers for accurate joint localization. Estimation accuracy was quantified using the mean squared error (MSE) for the estimated joints and the percentage of correct parts (PCP) for the body parts. The results show that the joint MSEs for the head and neck were lowest, and the PCP was highest for the torso. The PCP for individual activities ranged from 0.71 to 0.92, while typing and standing in a relaxed manner were the activities with the highest PCP. Estimation accuracy was higher for relatively still activities and lower for activities involving wide-ranging arm or leg motion. This study thus highlights the potential for the accurate estimation of occupant indoor activities by proposing a novel DNN model. This approach holds significant promise for finding the actual type of occupant activities and for use in target indoor applications related to thermal comfort in buildings.

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How Can We Adapt Thermal Comfort for Disabled Patients? A Case Study of French Healthcare Buildings in Summer

Energies ◽

10.3390/en14154530 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4530

Author(s):

Youcef Bouzidi ◽

Zoubayre El Akili ◽

Antoine Gademer ◽

Nacef Tazi ◽

Adil Chahboun

Keyword(s):

Thermal Comfort ◽

Thermal Environment ◽

Residential Buildings ◽

Linear Regression Analysis ◽

Environmental Parameters ◽

Physical Parameters ◽

Mean Radiant Temperature ◽

Operative Temperature ◽

Neutral Temperature ◽

Radiant Temperature

This paper investigates adaptive thermal comfort during summer in medical residences that are located in the French city of Troyes and managed by the Association of Parents of Disabled Children (APEI). Thermal comfort in these buildings is evaluated using subjective measurements and objective physical parameters. The thermal sensations of respondents were determined by questionnaires, while thermal comfort was estimated using the predicted mean vote (PMV) model. Indoor environmental parameters (relative humidity, mean radiant temperature, air temperature, and air velocity) were measured using a thermal environment sensor during the summer period in July and August 2018. A good correlation was found between operative temperature, mean radiant temperature, and PMV. The neutral temperature was determined by linear regression analysis of the operative temperature and Fanger’s PMV model. The obtained neutral temperature is 23.7 °C. Based on the datasets and questionnaires, the adaptive coefficient α representing patients’ capacity to adapt to heat was found to be 1.261. A strong correlation was also observed between the sequential thermal index n(t) and the adaptive temperature. Finally, a new empirical model of adaptive temperature was developed using the data collected from a longitudinal survey in four residential buildings of APEI in summer, and the obtained adaptive temperature is 25.0 °C with upper and lower limits of 24.7 °C and 25.4 °C.

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INCREASING MEAN SKIN TEMPERATURE LINEARLY REDUCES THE VASOCONSTRICTION AND SHIVERING THRESHOLDS IN HUMANS

Anesthesiology ◽

10.1097/00000542-199409001-00251 ◽

1994 ◽

Vol 81 (SUPPLEMENT) ◽

pp. A252

Author(s):

C. Cheng ◽

T. Matsukawa ◽

A. Kurz ◽

D. I. Sessler ◽

B. Merrifield

Keyword(s):

Skin Temperature ◽

Mean Skin Temperature

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Thermoregulatory responses during competitive marathon running

Journal of Applied Physiology ◽

10.1152/jappl.1977.42.6.909 ◽

1977 ◽

Vol 42 (6) ◽

pp. 909-914 ◽

Cited By ~ 98

Author(s):

M. B. Maron ◽

J. A. Wagner ◽

S. M. Horvath

Keyword(s):

Skin Temperature ◽

Marathon Running ◽

Heat Illness ◽

Mean Skin Temperature ◽

Total Water ◽

Water Losses ◽

Thermoregulatory Responses ◽

Marked Disparity ◽

Skin Temperatures ◽

Cool Conditions

To assess thermoregulatory responses occuring under actual marathon racing conditions, rectal (Tre) and five skin temperatures were measured in two runners approximately every 9 min of a competitive marathon run under cool conditions. Race times and total water losses were: runner 1 = 162.7 min, 3.02 kg; runner 2 = 164.6 min, 2.43 kg. Mean skin temperature was similar throughout the race in the two runners, although they exhibited a marked disparity in temperature at individual skin sites. Tre plateaued after 35--45 min (runner 1 = 40.0--40.1, runner 2 = 38.9--39.2 degrees C). While runner 2 maintained a relatively constant level for the remainder of the race, runner 1 exhibited a secondary increase in Tre. Between 113 and 119 min there was a precipitous rise in Tre from 40.9 to 41.9 degrees C. Partitional calorimetric calculations suggested that a decrease in sweating was responsible for this increment. However, runner 1's ability to maintain his high Tre and running pace for the remaining 44 min of the race and exhibit no signs of heat illness indicated thermoregulation was intact.

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