Resting energy expenditure differs among individuals with different levels of perceived thermal sensitivity: A cross-sectional study.

Metabolic rate has been used in thermophysiological models for predicting the thermal response of humans. However, only a few studies have investigated the association between an individual's trait-like thermal sensitivity and resting energy expenditure (REE), which resulted in inconsistent results. This study aimed to explore the association between REE and perceived thermal sensitivity. The REE of healthy adults was measured using an indirect calorimeter, and perceived thermal intolerance and sensation in the body were evaluated using a self-administered questionnaire. In total, 1567 individuals were included in the analysis (women = 68.9%, age = 41.1 ±â€…13.2 years, body mass index = 23.3 ±â€…3.3 kg/m2, REE = 1532.1 ±â€…362.4 kcal/d). More women had high cold intolerance (31.8%) than men (12.7%), and more men had high heat intolerance (23.6%) than women (16.1%). In contrast, more women experienced both cold (53.8%) and heat (40.6%) sensations in the body than men (cold, 29.1%; heat, 27.9%). After adjusting for age, fat-free mass, and fat mass, lower cold intolerance, higher heat intolerance, and heat sensation were associated with increased REE only in men (cold intolerance, P for trend = .001; heat intolerance, P for trend = .037; heat sensation, P = .046), whereas cold sensation was associated with decreased REE only in women (P = .023). These findings suggest a link between the perceived thermal sensitivity and REE levels in healthy individuals.

The temperature sensor TWA1 is required for thermotolerance in Arabidopsis.

Plants exposed to incidences of excessive temperatures activate heat-stress responses to cope with the physiological challenge and stimulate long-term acclimation1,2. The mechanism that senses cellular temperature for inducing thermotolerance is still unclear3. Here we show that TWA1 is a temperature-sensing transcriptional co-regulator that is needed for basal and acquired thermotolerance in Arabidopsis thaliana. At elevated temperatures, TWA1 changes its conformation and allows physical interaction with JASMONATE-ASSOCIATED MYC-LIKE (JAM) transcription factors and TOPLESS (TPL) and TOPLESS-RELATED (TPR) proteins for repressor complex assembly. TWA1 is a predicted intrinsically disordered protein that has a key thermosensory role functioning through an amino-terminal highly variable region. At elevated temperatures, TWA1 accumulates in nuclear subdomains, and physical interactions with JAM2 and TPL appear to be restricted to these nuclear subdomains. The transcriptional upregulation of the heat shock transcription factor A2 (HSFA2) and heat shock proteins depended on TWA1, and TWA1 orthologues provided different temperature thresholds, consistent with the sensor function in early signalling of heat stress. The identification of the plant thermosensors offers a molecular tool for adjusting thermal acclimation responses of crops by breeding and biotechnology, and a sensitive temperature switch for thermogenetics.

The comprehensive impact of thermal-PM2.5 interaction on subjective evaluation of urban outdoor space: A pilot study in a cold region of China.

Urban outdoor space has a very important impact on the quality of people's outdoor activities, which has influenced people's health and moods. Its influence is the result of the combined action of various factors. Thermal and air quality environment are important factors affecting the overall comfort of the urban outdoor space. At present, there are few research on interaction with thermal and air quality environment. Therefore, a meteorological measurement and questionnaire survey have been conducted in a representative open space in a campus in Xi'an, China. The following are the research results:(1) Mean physiological equivalent temperature (MPET) is a significant factor affecting thermal sensation vote (TSV) and thermal comfort vote (TCV). PM2.5 has no significant effect on thermal comfort vote (TCV), but it is a considerable factor affecting thermal sensation vote (TSV) when 10.2°C ≤ MPET<21°C (P = 0.023 *). (2) PM2.5 is a significant factor affecting air quality vote (AQV) and breathing comfort vote (BCV).Mean physiological equivalent temperature (MPET) has no significant impact on air quality vote (AQV), but it is a considerable factor affecting breathing comfort vote (BCV) when 10.2°C ≤ MPET<21°C (P = 0.01 **). (3) Mean physiological equivalent temperature (MPET) is a significant factor affecting overall comfort vote (OCV), but PM2.5 is not. In general, When 10.2°C ≤ MPET<21°C (-0.5 < -0.37 ≤ TCV ≤ 0.12 <0.5), the interaction between thermal and PM2.5 environment is significant on thermal sensation vote (TSV) and breathing comfort vote (BCV). This study can provide experimental support for the field of multi-factor interaction, which has shown that improving the thermal environment can better breathing comfort, while reducing PM2.5 concentration can promote thermal comfort. And can also provide reference for the study of human subjective comfort in urban outdoor space in the same latitude of the world.

A study of acoustic-light-thermal effects on pedestrians' overall comfort in a Cfa-climate campus during the summer.

The environmental quality, in terms of acoustic, visual, and thermal environments, significantly affects people's comfort levels. Along these lines, in this work, their comprehensive impact on people's overall comfort was systematically explored. Pedestrians' outdoor neutral points on various environmental parameters were found by performing linear regressions. Similarly, people's thermal perceptions (indicated by neutral temperatures, NT) were found to vary for both acoustic and light environments. They would be increasingly heat sensitive (R2 increases) in a noisier environment while the NTs varied for either sound or light intensity levels. From our analysis, it was demonstrated that people's overall comforts were negatively correlated with these parameters in different degrees. This work provides valuable insights for future urban design and planning studies to create better outdoor environments.

Evidence of heat sensitivity in people with Parkinson's disease.

Examining how heat affects people with Parkinson's disease is essential for informing clinical decision-making, safety, well-being, and healthcare planning. While there is evidence that the neuropathology associated with Parkinson's disease affects thermoregulatory mechanisms, little attention has been given to the association of heat sensitivity to worsening symptoms and restricted daily activities in people with this progressive disease. Using a cross-sectional study design, we examined the experiences of people diagnosed with Parkinson's disease in the heat. Two-hundred and forty-seven people completed an online survey (age: 66.0 ± 9.2 years; sex: male = 102 (41.3%), female = 145 (58.7%)), of which 195 (78.9%) reported becoming more sensitive to heat with Parkinson's disease. Motor and nonmotor symptoms worsened with heat in 182 (73.7%) and 203 (82.2%) respondents, respectively. The most commonly reported symptoms to worsen included walking difficulties, balance impairment, stiffness, tremor, fatigue, sleep disturbances, excess sweating, difficulty concentrating, and light-headedness when standing. Concerningly, over half indicated an inability to work effectively in the heat, and nearly half reported that heat impacted their ability to perform household tasks and social activities. Overall, heat sensitivity was common in people with Parkinson's disease and had a significant impact on symptomology, day-to-day activities and quality of life.

Enhancing thermal comfort prediction in high-speed trains through machine learning and physiological signals integration.

Heating, Ventilation, and Air Conditioning (HVAC) systems in high-speed trains (HST) are responsible for consuming approximately 70% of non-operational energy sources, yet they frequently fail to ensure provide adequate thermal comfort for the majority of passengers. Recent advancements in portable wearable sensors have opened up new possibilities for real-time detection of occupant thermal comfort status and timely feedback to the HVAC system. However, since occupant thermal comfort is subjective and cannot be directly measured, it is generally inferred from thermal environment parameters or physiological signals of occupants within the HST compartment. This paper presents a field test conducted to assess the thermal comfort of occupants within HST compartments. Leveraging physiological signals, including skin temperature, galvanic skin reaction, heart rate, and ambient temperature, we propose a Predicted Thermal Comfort (PTC) model for HST cabin occupants and establish an intelligent regulation model for the HVAC system. Nine input factors, comprising physiological signals, individual physiological characteristics, compartment seating, and ambient temperature, were formulated for the PTS model. In order to obtain an efficient and accurate PTC prediction model for HST cabin occupants, we compared the accuracy of different subsets of features trained by Machine Learning (ML) models of Random Forest, Decision Tree, Vector Machine and K-neighbourhood. We divided all the predicted feature values into four subsets, and did hyperparameter optimisation for each ML model. The HST compartment occupant PTC prediction model trained by Random Forest model obtained 90.4% Accuracy (F1 macro = 0.889). Subsequent sensitivity analyses of the best predictive models were then performed using SHapley Additive explanation (SHAP) and data-based sensitivity analysis (DSA) methods. The development of a more accurate and operationally efficient thermal comfort prediction model for HST occupants allows for precise and detailed feedback to the HVAC system. Consequently, the HVAC system can make the most appropriate and effective air supply adjustments, leading to improved satisfaction rates for HST occupant thermal comfort and the avoidance of energy wastage caused by inaccurate and untimely predictive feedback.

Influences of Indoor Air Temperatures on Empathy and Positive Affect.

The consequences of climate change are already visible, and yet, its effect on psychosocial factors, including the expression of empathy, affect, and social disconnection, is widely unknown. Outdoor conditions are expected to influence indoor conditions. Therefore, the aim of this study was to investigate the effect of indoor air temperature during work hours on empathy, positive and negative affect, and social disconnection. Participants (N = 31) were exposed, in a cross-over design, to two thermal conditions in a simulated office environment. Questions on empathy and social disconnection were administered before and after the exposure to each condition, while affect was measured throughout the day. Subjective thermal sensation and objective measures of mean skin temperature were considered. The results indicated a significant difference in empathy (F(1, 24) = 5.37, p = 0.03, with an η2 = 0.126) between conditions. Participants reported increases in empathy after exposure to the warm condition compared to the cool condition, in which reductions in empathy were reported. Although the same pattern was observed for positive affect, the difference was smaller and the results were not significant. Thermal sensation had a significant effect on changes in empathy too (F(1, 54) = 7.015, p = 0.01, with an R2 = 0.115), while mean skin temperature had no effect on empathy (F(1, 6) = 0.53, p = 0.89, with an R2 = 0.81). No effects were observed for positive and negative affect and social disconnection. Longitudinal studies are needed to support these findings.

High-resolution projections of outdoor thermal stress in the twenty-first century: a Tasmanian case study.

To adapt to Earth's rapidly changing climate, detailed modelling of thermal stress is needed. Dangerous stress levels are becoming more frequent, longer, and more severe. While traditional measurements of thermal stress have focused on air temperature and humidity, modern measures including radiation and wind speed are becoming widespread. However, projecting such indices has presented a challenging problem, due to the need for appropriate bias correction of multiple variables that vary on hourly timescales. In this paper, we aim to provide a detailed understanding of changing thermal stress patterns incorporating modern measurements, bias correction techniques, and hourly projections to assess the impact of climate change on thermal stress at human scales. To achieve these aims, we conduct a case study of projected thermal stress in central Hobart, Australia for 2040-2059, compared to the historical period 1990-2005. We present the first hourly metre-scale projections of thermal stress driven by multivariate bias-corrected data. We bias correct four variables from six dynamically downscaled General Circulation Models. These outputs drive the Solar and LongWave Environmental Irradiance Geometry model at metre scale, calculating mean radiant temperature and the Universal Thermal Climate Index. We demonstrate that multivariate bias correction can correct means on multiple time scales while accurately preserving mean seasonal trends. Changes in mean air temperature and UTCI by hour of the day and month of the year reveal diurnal and annual patterns in both temporal trends and model agreement. We present plots of future median stress values in the context of historical percentiles, revealing trends and patterns not evident in mean data. Our modelling illustrates a future Hobart that experiences higher and more consistent numbers of hours of heat stress arriving earlier in the year and extending further throughout the day.

Improving the operational forecasts of outdoor Universal Thermal Climate Index with post-processing.

The Universal Thermal Climate Index (UTCI) is a thermal comfort index that describes how the human body experiences ambient conditions. It has units of temperature and considers physiological aspects of the human body. It takes into account the effect of air temperature, humidity, wind, radiation, and clothes. It is increasingly used in many countries as a measure of thermal comfort for outdoor conditions, and its value is calculated as part of the operational meteorological forecast. At the same time, forecasts of outdoor UTCI tend to have a relatively large error caused by the error of meteorological forecasts. In Slovenia, there is a relatively dense network of meteorological stations. Crucially, at these stations, global solar radiation measurements are performed continuously, which makes estimating the actual value of the UTCI more accurate compared to the situation where no radiation measurements are available. We used seven years of measurements in hourly resolution from 42 stations to first verify the operational UTCI forecast for the first forecast day and, secondly, to try to improve the forecast via post-processing. We used two machine-learning methods, linear regression, and neural networks. Both methods have successfully reduced the error in the operational UTCI forecasts. Both methods reduced the daily mean error from about 2.6 ∘ C to almost zero, while the daily mean absolute error decreased from 5 ∘ C to 3 ∘ C for the neural network and 3.5 ∘ C for linear regression. Both methods, especially the neural network, also substantially reduced the dependence of the error on the time of the day.

Dynamic temperature control in microfluidics for in vivo imaging of cold-sensing in C. elegans.

The ability to perceive temperature is crucial for most animals. It enables them to maintain their body temperature and swiftly react to noxiously cold or hot objects. Caenorhabditis elegans is a powerful genetic model for the study of thermosensation as its simple nervous system is well characterized and its transparent body is suited for in vivo functional imaging of neurons. The behavior triggered by experience-dependent thermosensation has been well studied in C. elegans under temperature-gradient environments. However, how C. elegans senses temperature via its nervous system is not well understood due to the limitations of currently available technologies. One major bottleneck is the difficulty in creating fast temperature changes, especially cold stimuli. Here, we developed a microfluidic-based platform that allowed the in vivo functional imaging of C. elegans responding to well-controlled temporally varying temperature stimulation by rapidly switching fluid streams at different temperatures. We used computational models to enable rational design and optimization of experimental conditions. We validated the design and utility of our system with studies of the functional role of thermosensory neurons. We showed that the responses of PVD polymodal nociceptor neurons observed in previous studies can be recapitulated. Further, we highlighted how this platform may be used to dissect neuronal circuits with an example of activity recording in PVC interneurons. Both of these neuron types show sensitization phenotypes. We envision that both the engineered system and the findings in this work will spur further studies of molecular and cellular mechanisms underlying cold-sensing through the nervous system.

Physiological and perceptual responses to temperature step changes between cold and hot environments.

Objectives. This study explores the effects of temperature steps on thermal responses to understand abrupt temperature shifts faced by heat-exposed workers during winter. Methods. Three temperature step changes with three phases (S20: 20-40-20 °C, S30: 10-40-10 °C, S40: 0-40-0 °C) were conducted. Phase 1 took 30 min, phase 2 took 60 min and phase 3 took 40 min. Eleven participants remained sedentary throughout the experiment, and physiological responses, thermal perception and self-reported health symptoms were recorded. Results. In temperature up steps, steady skin temperature and sweating onset were delayed, and heart rate dropped by 10 bpm from S20 to S40. In temperature down steps to cold conditions, individuals transitioned from thermal comfort to discomfort and eventually cold strain. Blood pressure increased in temperature down steps, correlating with temperature step magnitudes. Thermal responses to temperature steps of equal magnitude but opposite directions were asymmetries, which weakened as step magnitude increased. Thermal perceptions responded faster than physiological changes after temperature steps, while self-reported health symptoms lagged behind physiological responses. Conclusions. These findings contribute to expanding basic data to understand the effects of temperature step magnitude and direction.

A brainstem-hypothalamus neuronal circuit reduces feeding upon heat exposure.

Empirical evidence suggests that heat exposure reduces food intake. However, the neurocircuit architecture and the signalling mechanisms that form an associative interface between sensory and metabolic modalities remain unknown, despite primary thermoceptive neurons in the pontine parabrachial nucleus becoming well characterized1. Tanycytes are a specialized cell type along the wall of the third ventricle2 that bidirectionally transport hormones and signalling molecules between the brain's parenchyma and ventricular system3-8. Here we show that tanycytes are activated upon acute thermal challenge and are necessary to reduce food intake afterwards. Virus-mediated gene manipulation and circuit mapping showed that thermosensing glutamatergic neurons of the parabrachial nucleus innervate tanycytes either directly or through second-order hypothalamic neurons. Heat-dependent Fos expression in tanycytes suggested their ability to produce signalling molecules, including vascular endothelial growth factor A (VEGFA). Instead of discharging VEGFA into the cerebrospinal fluid for a systemic effect, VEGFA was released along the parenchymal processes of tanycytes in the arcuate nucleus. VEGFA then increased the spike threshold of Flt1-expressing dopamine and agouti-related peptide (Agrp)-containing neurons, thus priming net anorexigenic output. Indeed, both acute heat and the chemogenetic activation of glutamatergic parabrachial neurons at thermoneutrality reduced food intake for hours, in a manner that is sensitive to both Vegfa loss-of-function and blockage of vesicle-associated membrane protein 2 (VAMP2)-dependent exocytosis from tanycytes. Overall, we define a multimodal neurocircuit in which tanycytes link parabrachial sensory relay to the long-term enforcement of a metabolic code.

The effects of brightness and prominent colors on outdoor thermal perception in Chongqing, China.

Outdoor thermal comfort has become an important factor affecting human mental and physical health due to rapid urbanization. This study aimed to investigate the influence of brightness and prominent colors on thermal perception in hot summer and cold winter regions. Meteorological measurements were conducted accompanied by subjective thermal and visual questionnaires (n = 2020) during summer and winter. The physiological equivalent temperature (PET) was applied as thermal indices to evaluate the influence of visual conditions on thermal perception. The results showed that (1) the neutral PET is 20.2 °C with a range of 14.8 ~ 25.7 °C in Chongqing and neutral illumination range is 0 ~ 8663 lx. (2) Thermal sensitivity is most great in neutral brightness than bright and too bright groups. The influence of outdoor prominent colors in winter supports hue-heat hypothesis. However, in summer, result only supports the hypothesis under low thermal stress. Both cool and warm colors can reduce the thermal sensitivity of visitors compared to neutral colors (gray and white). (3) The interactions between colors and brightness are more obvious under low thermal stress levels. (4) Thermal perceptions of females are more greatly affected by brightness and prominent colors compared with males. These results could help landscape designers better understand the correlation between the thermal and visual environments and provide a reference for comprehensive designs of urban open spaces.

Burning Question: How Does Our Brain Process Positive and Negative Cues Associated with Thermosensation?

Whether it is the dramatic suffocating sensation from a heat wave in the summer or the positive reinforcement arising from a hot drink on a cold day; we can certainly agree that our thermal environment underlies our daily rhythms of sensation. Extensive research has focused on deciphering the central circuits responsible for conveying the impact of thermogenesis on mammalian behavior. Here, we revise the recent literature responsible for defining the behavioral correlates that arise from thermogenic fluctuations in mammals. We transition from the physiological significance of thermosensation to the circuitry responsible for the autonomic or behavioral responses associated with it. Subsequently, we delve into the positive and negative valence encoded by thermoregulatory processes. Importantly, we emphasize the crucial junctures where reward, pain, and thermoregulation intersect, unveiling a complex interplay within these neural circuits. Finally, we briefly outline fundamental questions that are pending to be addressed in the field. Fully deciphering the thermoregulatory circuitry in mammals will have far-reaching medical implications. For instance, it may lead to the identification of novel targets to overcome thermal pain or allow the maintenance of our core temperature in prolonged surgeries.

Plant thermosensors.

Plants dynamically regulate their genes expression and physiological outputs to adapt to changing temperatures. The underlying molecular mechanisms have been extensively studied in diverse plants and in multiple dimensions. However, the question of exactly how temperature is detected at molecular level to transform the physical information into recognizable intracellular signals remains continues to be one of the undetermined occurrences in plant science. Recent studies have provided the physical and biochemical mechanistic breakthrough of how temperature changes can influence molecular thermodynamically stability, thus changing molecular structures, activities, interaction and signaling transduction. In this review, we focus on the thermosensing mechanisms of recognized and potential plant thermosensors, to describe the multi-level thermal input system in plants. We also consider the attributes of a thermosensor on the basis of thermal-triggered changes in function, structure, and physical parameters. This study thus provides a reference for discovering more plant thermosensors and elucidating plant thermal adaptive mechanisms.

Separation of Oral Cooling and Warming Requires TRPM8.

Cooling sensations arise inside the mouth during ingestive and homeostasis behaviors. Oral presence of cooling temperature engages the cold and menthol receptor TRPM8 (transient receptor potential melastatin 8) on trigeminal afferents. Yet, how TRPM8 influences brain and behavioral responses to oral temperature is undefined. Here we used in vivo neurophysiology to record action potentials stimulated by cooling and warming of oral tissues from trigeminal nucleus caudalis neurons in female and male wild-type and TRPM8 gene deficient mice. Using these lines, we also measured orobehavioral licking responses to cool and warm water in a novel, temperature-controlled fluid choice test. Capture of antidromic electrophysiological responses to thalamic stimulation identified that wild-type central trigeminal neurons showed diverse responses to oral cooling. Some neurons displayed relatively strong excitation to cold <10°C (COLD neurons) while others responded to only a segment of mild cool temperatures below 30°C (COOL neurons). Notably, TRPM8 deficient mice retained COLD-type but lacked COOL cells. This deficit impaired population responses to mild cooling temperatures below 30°C and allowed warmth-like (≥35°C) neural activity to pervade the normally innocuous cool temperature range, predicting TRPM8 deficient mice would show anomalously similar orobehavioral responses to warm and cool temperatures. Accordingly, TRPM8 deficient mice avoided both warm (35°C) and mild cool (≤30°C) water and sought colder temperatures in fluid licking tests, whereas control mice avoided warm but were indifferent to mild cool and colder water. Results imply TRPM8 input separates cool from warm temperature sensing and suggest other thermoreceptors also participate in oral cooling sensation.

Analysis of the correlation mechanism between geometric parameters and the thermal environment of Xi'an's summer outdoor commercial pedestrian streets.

Intensive urban development has resulted in the degradation of the urban thermal environment in most regions. There is a growing consensus on the need to enhance urban thermal comfort through well-designed forms, especially in open spaces like urban canyons. To address this, our study focuses on Xi'an's commercial pedestrian streets, employing K-means clustering analysis to create 32 representative models based on actual scenes, capturing their textural characteristics. Simultaneously, 11 geometric indicators (2D/3D) were chosen to quantify the canyon's geometric form. We assessed the spatial and temporal distribution differences in the thermal environment across these models using Envi-met simulation. Finally, Spearman correlation analysis was employed to examine the correlation and significance of the two sets of indicators, culminating in formulating an ideal model. The findings reveal that (1) wind conditions are predominantly influenced by the canyon's geometric form, followed by solar radiation and temperature, with the lowest relative humidity change amplitude among the assessed thermal parameters. (2) Among the 11 geometric form indicators, 3D indicators correlate more significantly with thermal environment parameters than 2D indicators. Specifically, street orientation significantly impacts the thermal environment, Build-To-Line Rat holds greater significance than interface density, and both building shape coefficient and block surface ratio are significantly correlated with air temperature and wind speed, with a weaker correlation to solar radiation. (3) In the Xi'an region, courtyards oriented north-south demonstrate a more favorable trend in the thermal environment.

Thermal stress and comfort assessment in urban areas using Copernicus Climate Change Service Era 5 reanalysis and collected microclimatic data.

In this initial study of a research project, this paper seeks to understand the thermal conditions in the cities of Lisbon and Munich, specifically focusing on Urban Heat Island intensity and on thermal comfort using the Universal Thermal Climate Index modeling data at the Local Climate Zone scale. Based on these datasets, Munich has exhibited more unfavourable thermal conditions than Lisbon. In terms of UHII, both cities have shown that low, medium, and high rise compact urban areas and bare rock or paved areas have the highest values, while sparsely built areas have the lowest. These results differ from the UTCI, which indicates that in Lisbon and Munich, these sparsely built areas as well as areas with low plants and vegetation are the most uncomfortable. In Munich, the population was exposed to very strong heat stress, while Lisbon experienced strong heat stress conditions. Conversely, low, medium, and high rise compact urban areas and densely wooded areas in Munich, and scattered trees areas and large low-rise urban areas in Lisbon, have demonstrated the lowest monthly mean and average maximum values. These results will be further explored in future studies in the city of Lisbon and cross-checked with data obtained from roving missions. This will enable a more detailed temporal and local analysis.

A seasonal comparison of a 14-day swing on cognitive function and psycho-physiological responses in mine service workers.

This study assessed the effect of season on cognitive function and psycho-physiological responses during a 14-day swing in mine-service workers. Cognitive function, thermal sensation and comfort, rating of perceived exertion, fatigue, hydration, core temperature and heart rate were assessed throughout a shift, on three separate days over a swing. Working memory and processing efficiency did not differ between seasons (p > 0.05), however counting and recall latencies improved throughout the swing (p < 0.05). Participants reported greater fatigue post-shift compared to pre-shift (p < 0.05). Thermal sensation, thermal comfort, and hydration were significantly elevated in summer compared to winter (p < 0.05). Specifically, workers were significantly/minimally dehydrated in summer/winter (urinary specific gravity = 1.025 ± 0.007/1.018 ± 0.007). Although cognitive function and thermal strain were not impaired in summer compared to winter, it is essential to reinforce worker's knowledge regarding hydration requirements. Additional education and/or incorporating scheduled rest breaks for hydration should be considered to ensure the health and safety of mine workers.