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This gait biomechanics study investigated stride length (SL), stride duration (SDN), the peak values of ground reaction forces (GRFspeak), required coefficient of friction (RCOFpeak), leg joints’ angles (anglepeak), angular velocity (angvelx.peak), angular acceleration (angaccx.peak), minimum angle (anglemin.) of the foot, and muscles’ electromyography (EMG) during the stance phase (SP) of the dominant leg following an exhaustive stair ascent on a stair machine. Data were collected by a three-dimensional motion capture system synchronized with EMG and force plate while walking down a 10° inclined stationary walkway. Although the leg muscles’ EMG showed no significant local muscle fatigue (LMF) during post-exhaustive walking downwards, the SL was significantly (p peak. was significantly (p ≤ .01) reduced during late stance (LS) phase, however, the antero-posterior GRFypeak. was found to be significantly (p ≤ 0.01) higher. The RCOFpeak. was significantly (p ≤ .05) higher during the post-exhaustive walking downwards, LS phase. The available coefficient of friction value of ~ 0.350 seems to be the RCOF to reduce slips and falls on an inclined dry surface. None of the post-exhaustive lower limb joints’ anglepeak, anglemin., ang.velx.peak, and ang.accx.peak were significantly changed in post-exhaustion walking, except the knee ang.accx.peak., which was significantly (p

To provide a primer specifically for the field of maternal perinatal health on heat stress and heat indices. An updated review of maternal health studies (n=374) and heat indices (n=25) was carried out using Scopus, in addition to the PubMed review carried out in Cherisch et al., 2020. Here, the methodology is outlined for the scoping review.

This paper describes the functional development of the ClimApp tool (available for free on iOS and Android devices), which combines current and 24 h weather forecasting with individual information to offer personalised guidance related to thermal exposure. Heat and cold stress assessments are based on ISO standards and thermal models where environmental settings and personal factors are integrated into the ClimApp index ranging from −4 (extremely cold) to +4 (extremely hot), while a range of −1 and +1 signifies low thermal stress. Advice for individuals or for groups is available, and the user can customise the model input according to their personal situation, including activity level, clothing, body characteristics, heat acclimatisation, indoor or outdoor situation, and geographical location. ClimApp output consists of a weather summary, a brief assessment of the thermal situation, and a thermal stress warning. Advice is provided via infographics and text depending on the user profile. ClimApp is available in 10 languages: English, Danish, Dutch, Swedish, Norwegian, Hellenic (Greek), Italian, German, Spanish and French. The tool also includes a research functionality providing a platform for worker and citizen science projects to collect individual data on physical thermal strain and the experienced thermal strain. The application may therefore improve the translation of heat and cold risk assessments and guidance for subpopulations. ClimApp provides the framework for personalising and downscaling weather reports, alerts and advice at the personal level, based on GPS location and adjustable input of individual factors.

In recent years, air ventilation garments (AVG) have been reported effective to improve thermal comfort. In this study, an AVG incorporated with small fans was investigated on torso thermal comfort in moderate environment (Ta=25 °C, RH=50 %). Eight female subjects walked on the treadmill at a speed of 4 km·h−1 for 30 min and then rested for another 30 min. During the whole test protocol, the AVG was worn in three conditions of flow rates to examine which flow rate was the best choice to keep thermal comfort: fans off with no air ventilation (a controlled condition, CON), low flow rate (12 l/s, LOW) and high flow rate (20 l/s, HIGH). Results showed that HIGH made significantly lowered local skin temperature of the abdomen, scapula and the lower back (p

Stair-ascending at maximum ability is required during emergency evacuations to reach a safe refuge from deep underground structures. We hypothesized that an ascent can last maximum 5 min at the individual’s maximum step rate (SR), and oxygen uptake $$ ( {\dot{V}}{\text{O}}_{2} ) $$ ( V ˙ O 2 ) would not reach a stable state. This study explored stair-ascending endurance and some physiological constraints of performance. Eighteen healthy volunteers with mean (standard deviation, SD) age 26.7 (4.0) years, height 172.2 (10.7) cm, weight 68.0 (11.3) kg, BSA 1.8 (0.2) m−2, $$ {\dot{V}}{\text{O}}_{\rm 2max} $$ V ˙ O 2 max 48.5 (5.4) mL min−1 kg−1, and HRmax 192 (9) b min−1 ascended on a stair machine at a SR equivalent to their 100% $$ {\dot{V}}{\text{O}}_{\rm 2max} $$ V ˙ O 2 max . The mean (SD) ascending duration was 3.47 (1.18) min, supporting the hypothesis. The calculated vertical height covered was 85.5 (32.1) m. The $$ {\dot{V}}{\text{O}}_{\rm 2highest} $$ V ˙ O 2 highest reached 44.8 (7.3) mL min−1 kg−1, which was 92.3 (9.7)% of $$ {\dot{V}}{\text{O}}_{\rm 2max} $$ V ˙ O 2 max when the HRhighest peaked at 174 (11) b min−1. However, the mean $$ ( {\dot{V}}{\text{O}}_{2} ) $$ ( V ˙ O 2 ) reached a relatively steady state after the sharp rise. The post-ascent blood lactate, respiratory exchange ratio, and perceived exertion values recorded were high, 14.4 (4.0) mmol l−1, 1.20 (0.09), and 18.2 (0.7), respectively, indicated that exhaustion was reached. The ascending SR rate was above the lactate threshold; therefore, the attainment of $$ {\dot{V}}{\text{O}}_{\rm 2} $$ V ˙ O 2 steady state was slowly reached. EMG amplitudes of four major leg muscles increased and the median frequencies of two muscles decreased significantly (p −1) is possible to sustain 2–6 min. These overall results offer useful and vital information to consider when designing underground emergency evacuation facilities.

Climate change is adversely impacting the burden of diarrheal diseases. Despite significant reduction in global prevalence, diarrheal disease remains a leading cause of morbidity and mortality among young children in low- and middle-income countries. Previous studies have shown that diarrheal disease is associated with meteorological conditions but the role of large-scale climate phenomena such as El Niño-Southern Oscillation (ENSO) and monsoon anomaly is less understood. We obtained 13 years (2002–2014) of diarrheal disease data from Nepal and investigated how the disease rate is associated with phases of ENSO (El Niño, La Niña, vs. ENSO neutral) monsoon rainfall anomaly (below normal, above normal, vs. normal), and changes in timing of monsoon onset, and withdrawal (early, late, vs. normal). Monsoon season was associated with a 21% increase in diarrheal disease rates (Incident Rate Ratios [IRR]: 1.21; 95% CI: 1.16–1.27). El Niño was associated with an 8% reduction in risk while the La Niña was associated with a 32% increase in under-5 diarrheal disease rates. Likewise, higher-than-normal monsoon rainfall was associated with increased rates of diarrheal disease, with considerably higher rates observed in the mountain region (IRR 1.51, 95% CI: 1.19–1.92). Our findings suggest that under-5 diarrheal disease burden in Nepal is significantly influenced by ENSO and changes in seasonal monsoon dynamics. Since both ENSO phases and monsoon can be predicted with considerably longer lead time compared to weather, our findings will pave the way for the development of more effective early warning systems for climate sensitive infectious diseases.

The increase in average seasonal temperatures has an impact in the occupational field, especially for those sectors whose work activities are performed outdoors (agricultural, road and construction sectors). Among the adaptation measures and solutions developed to counteract occupational heat strain, personal cooling garments represent a wearable technology designed to remove heat from the human body, enhancing human performance. This study aims to investigate the effectiveness and the cooling power of a specific cooling garment, i.e. a ventilation jacket, by quantifying the evaporative heat losses and the total evaporative resistance both when worn alone and in combination with a work ensemble, at three adjustments of air ventilation speed. Standardised "wet" tests in a climatic chamber were performed on a sweating manikin in isothermal conditions considering three clothing ensembles (single jacket, work ensemble and a combination of both) and three adjustments of fan velocity. Results showed a significant increase (p 0.001) in evaporative heat loss values when the fan velocity increased, particularly within the trunk zones for all the considered clothing ensembles, showing that fans enhanced the dissipation by evaporation. The cooling power, quantified in terms of percent changes of evaporative heat loss, showed values exceeding 100% when fans were on, in respect to the condition of fans-off, for the trunk zones except for the Chest. A significant (p 0.01) decrease (up to 42.3%) in the total evaporative resistance values of the jacket, coupled with the work ensemble, was found compared to the fans-off condition. Results confirmed and quantified the cooling effect of the ventilation jacket which enhanced the evaporative heat losses of the trunk zones, helping the body to dissipate heat and showing the potential for a heat adaptation measure to be developed.

The ongoing climate change will elevate the incidence of diarrheal in 2030-2050 in Asia, including Taiwan. This study investigated associations between meteorological factors (temperature, precipitation) and burden of age-cause-specific diarrheal diseases in six regions of Taiwan using 13 years of (2004-2016) population-based data.Weekly cause-specific diarrheal and meteorological data were obtained from 2004 to 2016. We used distributed lag non-linear model to assess age (under five, all age) and cause-specific (viral, bacterial) diarrheal disease burden associated with extreme high (99th percentile) and low (5th percentile) of climate variables up to lag 8 weeks in six regions of Taiwan. Random-effects meta-analysis was used to pool these region-specific estimates.Extreme low temperature (15.30 °C) was associated with risks of all-infectious and viral diarrhea, with the highest risk for all-infectious diarrheal found at lag 8 weeks among all age [Relative Risk (RR): 1.44; 95 % Confidence Interval (95 % CI): 1.24-1.67]. The highest risk of viral diarrheal infection was observed at lag 2 weeks regardless the age. Extreme high temperature (30.18 °C) was associated with risk of bacterial diarrheal among all age (RR: 1.07; 95 % CI: 1.02-1.13) at lag 8 weeks. Likewise, extreme high precipitation (290 mm) was associated with all infectious diarrheal, with the highest risk observed for bacterial diarrheal among population under five years (RR: 2.77; 95 % CI: 1.60-4.79) at lag 8 weeks. Extreme low precipitation (0 mm) was associated with viral diarrheal in all age at lag 1 week (RR: 1.08; 95 % CI: 1.01-1.15)].In Taiwan, extreme low temperature is associated with an increased burden of viral diarrheal, while extreme high temperature and precipitation elevated burden of bacterial diarrheal. This distinction in cause-specific and climate-hazard specific diarrheal disease burden underscore the importance of incorporating differences in public health preparedness measures designed to enhance community resilience against climate change.

This guide presents a joint effort of projects funded under the European Research Area for Climate Services (ERA4CS) (http://www.jpi-climate.eu/ERA4CS), a co- funded action initiated by JPI Climate with co-funding by the European Union (Grant 690462), 15 national public Research Funding Organisations (RFOs), and 30 Research Performing Organisations (RPOs) from 18 European countries. This guide sets out to increase the understanding of different pathways, methods, and approaches to improve knowledge co-production of climate services with users as a value-added activity of the ERA4CS Programme. Reflecting on the experiences of 16 of the 26 projects funded under ERA4CS, this guide aims to define and recommend good practices for transdisciplinary knowledge co-production of climate services to researchers, users, funding agencies, and private sector service providers. Drawing on responses from ERA4CS project teams to a questionnaire and interviews, this guide maps the diversity of methods for stakeholder identification, involvement, and engagement. It also conducts an analysis of methods, tools, and mechanisms for engagement as well as evaluation of co-production processes. This guide presents and discusses good practice examples based on the review of the ERA4CS projects, identifying enablers and barriers for key elements in climate service co-production processes. These were: namely (i) Forms of Engagement; (ii) Entry Points for Engagement; and, (iii) Intensity of Involvement. It further outlines key ingredients to enhance the quality of co-producing climate services with users and stakeholders. Based on the analysis of the lessons learned from ERA4CS projects, as well as a review of key concepts in the recent literature on climate service co-production, we provide a set of recommendations for researchers, users, funders and private sector providers of climate services. This report is not externally peer-reviewedRevisions:2022-02-11 The report PDF was published.2022-05-06 An incorrect spelled author name was updated in the author list, and the published PDF has been exchanged. Before this date the PDF was downloaded 193 times.

Background: Occupational heat exposure can provoke health problems that increase the risk of certain diseases and affect workers’ ability to maintain healthy and productive lives. This study investigates the effects of occupational heat stress on workers’ physiological strain and labor productivity, as well as examining multiple interventions to mitigate the problem. Methods: We monitored 518 full work-shifts obtained from 238 experienced and acclimatized individuals who work in key industrial sectors located in Cyprus, Greece, Qatar, and Spain. Continuous core body temperature, mean skin temperature, heart rate, and labor productivity were collected from the beginning to the end of all work-shifts. Results: In workplaces where self-pacing is not feasible or very limited, we found that occupational heat stress is associated with the heat strain experienced by workers. Strategies focusing on hydration, work-rest cycles, and ventilated clothing were able to mitigate the physiological heat strain experienced by workers. Increasing mechanization enhanced labor productivity without increasing workers’ physiological strain. Conclusions: Empowering laborers to self-pace is the basis of heat mitigation, while tailored strategies focusing on hydration, work-rest cycles, ventilated garments, and mechanization can further reduce the physiological heat strain experienced by workers under certain conditions.

Thermal models and indices integrated into a mobile application could provide relevant information regarding thermal stress and strain to the general public. The aim of the current paper is to validate such a mobile application, ClimApp, to the users needs in the heat. ClimApp combines weather data with personal user data, thermal models and indices to estimate the thermal strain of the user. The output of ClimApp ranges from −4 to +4, where values below 0 indicate cold strain and values above 0 indicate heat strain. 134 Participants filled in the required personal settings into the app, and indicated if the estimated thermal strain by ClimApp matched their thermal perception. 45 of the participants filled in a user satisfaction questionnaire. Results show that ClimApp is able to predict the heat strain of the user, but may underestimate perceived heat strain when ambient temperature increases. Furthermore, participants were positive about the user-friendliness of ClimApp, but did not think they would use ClimApp frequently and believed the information was irrelevant for them. This is quite remarkable as the number of heat illness cases are increasing and the negative effects of heat occur in all populations exposing themselves to the heat. There needs to be more focus on making people aware of the negative health risks of the heat. ClimApp could play a role as a tool to make heat warnings more accessible for everyone and make people aware of appropriate behavior during periods with high ambient temperatures.

Background Despite increasing concerns about the health effects of climate change, the extent to which workers are affected by hot weather is not well documented. This study aims to investigate the association between high temperatures and work-related injuries using data from a large subtropical city in China. Methods We used workers’ compensation claims to identify work-related injuries in Guangzhou, China during 2011–2012. To feature the heat effect, the study period was restricted to the warm seasons in Guangzhou (1 May-31 October). We conducted a time-stratified case-crossover study to examine the association between ambient outdoor temperatures, including daily maximum and minimum temperatures, and cases of work-related injury. The relationships were assessed using conditional Poisson regression models. Results Overall, a total of 5418 workers’ compensation claims were included over the study period. Both maximum and minimum temperatures were significantly associated with work-related injuries, but associations varied by subgroup. One °C increase in maximum temperature was associated with a 1.4% (RR = 1.014, 95%CIs 1.012–1.017) increase in daily injury claims. Significant associations were seen for male and middle-aged workers, workers in small and medium-sized enterprises, and those working in manufacturing sector. And 1 °C increase in minimum temperature was associated with 1.7% (RR = 1.017, 95%CIs 1.012–1.021) increase in daily injury claims. Significant associations were observed for female and middle-aged workers, workers in large-sized enterprises, and those working in transport and construction sectors. Conclusions We found a higher risk of work-related injuries due to hot weather in Guangzhou, China. This study provides important epidemiological evidence for policy-makers and industry that may assist in the formulation of occupational safety and climate adaptation strategies.

Working and walking environments often involve standing positions on different surfaces with inclination and different friction. In this study, standing balance of thirteen participants during sudden and irregular external perturbation to calf muscles was investigated. The aim of the study was to evaluate the combined effect of surface inclination and friction on standing balance. The main findings when eyes closed revealed that the standing utilised coefficient of friction (mu(SUCOF)) increased when the surface was inclined for both high and low friction materials. The anteriorposterior torque increased more anteriorly when the surface was inclined toes down and when the surface friction was low. The results indicate that the anterior posterior torque is a sensitive parameter when evaluating standing balance ability and slip risk. On inclined surface, particularly on the surface with lower friction, the potential slip and fall risk is higher due to the increase of standing utilised coefficient of friction and increased forward turning torque. Validerad;2018;Nivå 2;2018-08-09 (andbra)

It is common practice in India to consume the dairy drink buttermilk as a way of mitigating occupational heat strain. This paper explores the thermoregulatory and hydration benefits of drinking buttermilk but also the impacts of work in a hot environment on the gut microbiota, renal and cognitive function. Twelve healthy participants were subjected to a 3-h period of medium load physical intermittent work in a climatic chamber (34°C, 60% RH). The subjects were given water, buttermilk (700 ml) or no rehydration at random. Mean body temperatures when no rehydration was given were significantly higher (p≤0.001). When subjects drank water or buttermilk they had a lower sweat rate than with no rehydration (p≤0.05) and the perception of feeling hot, uncomfortable, thirsty and physically exerted was significantly reduced (p≤0.05). A hormonal stress response at the end of the exposure was seen when not drinking (p≤0.05). No differences in cognitive abilities and gut microbiota were found. The exposure lowered the renal blood flow suggesting an acute impact of short term heat exposure. It was also found that buttermilk has a protective effect on this impact. Our results demonstrated that keeping hydrated by water/buttermilk consumption mitigates heat strain in well-nourished subjects.

Personal cooling garments (PCGs) can represent an adaptation solution to counteract heat strain and to improve worker's health and productivity (especially for some outdoor work activities as in agriculture and in the construction industry). The cooling effect of a ventilation jacket was preliminarily investigated carrying out “dry” tests in a climatic chamber on a thermal manikin. A standardized condition with air temperature, ta = 22.4 °C, three different adjustments of the fan velocity ( v f = 0, v f = 2 and v f = 4), and three different ensembles (the single jacket, a work ensemble and a combination of both) were considered. Results showed significant increases in dry heat losses (through convection) for the trunk thermal zones, higher when the fans were on, for all the ensembles considered. Percent changes greatly exceeded 100 % for the thermal zones close to the fans. The air ventilation determined significant decreases of the total thermal insulation ( I T ) values (up to 35 %) compared to the fans-off condition, confirming and quantifying the cooling effect of the ventilation jacket.

Global warming will unquestionably increase the impact of heat on individuals who work in already hot workplaces in hot climate areas. The increasing prevalence of this environmental health risk requires the improvement of assessment methods linked to meteorological data. Such new methods will help to reveal the size of the problem and design appropriate interventions at individual, workplace and societal level. The evaluation of occupational heat stress requires measurement of four thermal climate factors (air temperature, humidity, air velocity and heat radiation); available weather station data may serve this purpose. However, the use of meteorological data for occupational heat stress assessment is limited because weather stations do not traditionally and directly measure some important climate factors, e.g. solar radiation. In addition, local workplace environmental conditions such as local heat sources, metabolic heat production within the human body, and clothing properties, all affect the exchange of heat between the body and the environment. A robust occupational heat stress index should properly address all these factors. This article reviews and highlights a number of selected heat stress indices, indicating their advantages and disadvantages in relation to meteorological data, local workplace environments, body heat production and the use of protective clothing. These heat stress and heat strain indices include Wet Bulb Globe Temperature, Discomfort Index, Predicted Heat Strain index, and Universal Thermal Climate Index. In some cases, individuals may be monitored for heat strain through physiological measurements and medical supervision prior to and during exposure. Relevant protective and preventive strategies for alleviating heat strain are also reviewed and proposed.

Additional file 1: Appendix 1. search terms by category based on PICO table used for searching the databases. Appendix 2. Physiological effect size comparisons. Appendix 3. Physical performance effect size comparisons. Appendix 4. Cognitive performance effect size comparisons. Appendix 5. Perceptual response effect size comparisons.

This biomechanics study explored stride length (SL), stride duration (SDN), the peak of gait ground reaction forces (GRFspeak), required coefficient of friction (RCOFpeak), joints’ angle (anglepeak), angular velocity (angvelx peak), angular acceleration (angaccx peak), minimum angle (anglemin) of foot, and muscle electromyography (EMG) during the dominant leg stance phase (SP) following an exhaustive stair ascent for evacuation. Data were collected by a three-dimensional motion capture system synchronized with EMG and force plate when walking upwards on a 10° inclined walkway. The significantly (p ≤ .05) decreased EMG median frequencies of tibialis anterior during early (ES) and late stance (LS) phases, and vastus lateralis muscles during LS are the evidence of leg local muscle fatigue (LMF). The perpendicular and longitudinal shear GRFspeaks were significantly reduced during ES (p ≤ .05) and LS (p ≤ .01), respectively. The post-fatigue SP, SL, and SDN were significantly (p

Much of the 1950–1970s building stock in Sweden and other European countries is being renovated to reduce energy use and for general upgrading. To realize the UN Sustainable Development Goals, the renovations should also improve indoor environmental quality (IEQ). The PEIRE (People-Environment-Indoor-Renovation-Energy) study followed the renovation of a multifamily housing area in Sweden comprising 14 buildings with 323 dwellings in total. We aimed to investigate tenant perception of IEQ changes after the renovation with focus on perceived control of IEQ, recalling of being informed how to control IEQ, and if tenants with self-reported symptoms perceive the changes differently. A post-renovation survey (n = 104, response rate 36%) showed that the renovation increased the proportion of residents experiencing satisfactory thermal comfort and air quality in the winter, as well as improved noise conditions. Perceiving reduced draught in the thermal environment was associated with experiencing being informed and being able to control heat and ventilation. Respondents reporting skin irritation symptoms were less likely than others to perceive any improvements of IEQ factors such as air quality, daylight, noise from installations and neighbours, and periods of excessive heat. Renovations targeting housing sustainability – here, decreasing energy use and mitigating wear and tear while keeping the rents low – could increase tenant perceptions of improved IEQ, especially if factors concerning information and tenants’ ability to control the regulating systems are addressed. Interestingly, results of this study point out that tenants experiencing IEQ-related symptoms may require enhanced IEQ improvements to experience the renovation as satisfactory.

Climate change increases the risks of heat stress, especially in urban areas where urban heat islands can develop. This literature review aims to describe how severe heat can occur and be identified in urban indoor environments, and what actions can be taken on the local scale. There is a connection between the outdoor and the indoor climate in buildings without air conditioning, but the pathways leading to the development of severe heat levels indoors are complex. These depend, for example, on the type of building, window placement, the residential area’s thermal outdoor conditions, and the residents’ influence and behavior. This review shows that only few studies have focused on the thermal environment indoors during heat waves, despite the fact that people commonly spend most of their time indoors and are likely to experience increased heat stress indoors in the future. Among reviewed studies, it was found that the indoor temperature can reach levels 50% higher in °C than the outdoor temperature, which highlights the importance of assessment and remediation of heat indoors. Further, most Heat-Health Warning Systems (HHWS) are based on the outdoor climate only, which can lead to a misleading interpretation of the health effects and associated solutions. In order to identify severe heat, six factors need to be taken into account, including air temperature, heat radiation, humidity, and air movement as well as the physical activity and the clothes worn by the individual. Heat stress can be identified using a heat index that includes these six factors. This paper presents some examples of practical and easy to use heat indices that are relevant for indoor environments as well as models that can be applied in indoor environments at the city level. However, existing indexes are developed for healthy workers and do not account for vulnerable groups, different uses, and daily variations. As a result, this paper highlights the need for the development of a heat index or the adjustment of current thresholds to apply specifically to indoor environments, its different uses, and vulnerable groups. There are several actions that can be taken to reduce heat indoors and thus improve the health and well-being of the population in urban areas. Examples of effective measures to reduce heat stress indoors include the use of shading devices such as blinds and vegetation as well as personal cooling techniques such as the use of fans and cooling vests. Additionally, the integration of innovative Phase Change Materials (PCM) into facades, roofs, floors, and windows can be a promising alternative once no negative health and environmental effects of PCM can be ensured.

Energy efficiency measures in residential buildings typically include changes in ventilation and heating systems, and increased thermal insulation of the building envelope. The expected energy efficiency is not always reached, despite large knowledge and professional implementation of each separate measure. There is a lack in understanding of how technical systems interact, and how the occupants are influenced by and in turn influence the systems by their behaviour. A holistic view and a transdisciplinary research approach are needed to understand relevant interactions and propose integrated energy efficiency measures. The aim of this paper is to reveal challenges in transdisciplinary research projects that include real world studies on both humans and technical systems with measurements before and after renovation of multifamily housing. It is based on experiences from the PEIRE-project (People, Environment, Indoor, Renovation, Energy) carried out by a research team with expertise on environmental psychology, human behaviour, interaction design, universal design, building physics, building services, thermal comfort, aerosol technology, exposure assessment, acoustics, daylight, and complex thinking. Differences in theoretical bases and methodology needed to be dealt with. Metatheory building could help with the transition from a multi- to a transdisciplinary understanding.

This laboratory study examined human stair ascending capacity and constraining factors including legs’ local muscle fatigue (LMF) and cardiorespiratory capacity. Twenty-five healthy volunteers, with mean age 35.3 years, maximal oxygen uptake (VO2max) of 46.7 mL·min−1·kg−1 and maximal heart rate (HR) of 190 bpm, ascended on a stair machine at 60 and 75% (3 min each) and 90% of VO2max (5 min or until exhaustion). The VO2, maximal heart rate (HRmax) and electromyography (EMG) of the leg muscles were measured. The average VO2highest reached 43.9 mL·min−1·kg−1, and HRhighest peaked at 185 bpm at 90% of VO2max step rate (SR). EMG amplitudes significantly increased at all three levels, p

Indoor environments have a large impact on health and well-being, so it is important to understand what makes them healthy and sustainable. There is substantial knowledge on individual factors and their effects, though understanding how factors interact and what role occupants play in these interactions (both causative and receptive) is lacking. We aimed to: (i) explore interactions between factors and potential risks if these are not considered from holistic perspective, and (ii) identify components needed to advance research on indoor environments. The paper is based on collaboration between researchers from disciplines covering technical, behavioural, and medical perspectives. Outcomes were identified through literature reviews, discussions and workshops with invited experts and representatives from various stakeholder groups. Four themes emerged and were discussed with an emphasis on occupant health: (a) the bio-psycho-social aspects of health, (b) interaction between occupants, buildings and indoor environment, (c) climate change and its impact on indoor environment quality, thermal comfort and health, and (d) energy efficiency measures and indoor environment. To advance the relevant research, the indoor environment must be considered a dynamic and complex system with multiple interactions. This calls for a transdisciplinary and holistic approach and effective collaboration with various stakeholders.

The aim of the study was to identify whether a ventilation cooling shirt was effective in reducing heat strain in a hot climate. Eight female volunteers were exposed to heat (38 °C, 45% relative humidity) for 2 h with simulated office work. In the first hour they were in normal summer clothes (total thermal insulation 0.8 clo); in the second hour a ventilation cooling shirt was worn on top. After the shirt was introduced for 1 h, the skin temperatures at the scapula and the chest were significantly reduced (p

The purpose of the study was to investigate and compare the effect of two cooling garments with phase change material (PCM) and ventilation on thermal comfort. Eight female university students (age 24±1 years; height 162±4 cm; body weight 54±4 kg) exercised on a treadmill in an environment of 32 ℃ with 50 % relative humidity. Tests in three conditions were carried out after moderate exercise with t-shirt and shorts: cooling with a PCM vest (PCM); cooling with a ventilation jacket (VEN) and without cooling clothing (natural cooling, a control condition, CON). Results showed that no significant differences were observed in the mean skin temperature and heart rate among the two cooling garment conditions and the control condition (p>0.05). The local torso skin temperature was observed with significant difference among the three conditions (p

American standard ASTM F2732 estimates the lowest environmental temperature for thermal comfort for cold weather protective clothing. International standard ISO 11079 serves the same purpose but expresses cold stress in terms of required clothing insulation for a given cold climate. The objective of this study was to validate and compare the temperature ratings using human subject tests at two levels of metabolic rates (2 and 4 MET corresponding to 116.4 and 232.8 W/m(2)). Nine young and healthy male subjects participated in the cold exposure at 3.4 and -30.6 °C. The results showed that both standards predict similar temperature ratings for an intrinsic clothing insulation of 1.89 clo and for 2 MET activity. The predicted temperature rating for 2 MET activity is consistent with test subjects' thermophysiological responses, perceived thermal sensation and thermal comfort. For 4 MET activity, however, the whole body responses were on the cold side, particularly the responses of the extremities. ASTM F2732 is also limited due to its omission and simplification of three climatic variables (air velocity, radiant temperature and relative humidity) and exposure time in the cold which are of practical importance.

Global warming will unquestionably increase the impact of heat on individuals. The increasing prevalence of this environmental health risk requires the improvement of exposure assessment linked to meteorological data. Reliable assessments of heat stress and heat strain will help to reveal the size of the problem and design appropriate interventions at individual, workplace and societal level. However, it is common that air temperature is widely used as a single parameter in epidemiological studies on the effect of health. The evaluation of occupational heat stress requires measurement of four thermal climate factors (air temperature, humidity, air velocity and heat radiation); available weather station data may serve this purpose. However, the use of meteorological data for such assessment is limited because weather stations do not traditionally and directly measure some important climate factors, e.g. solar radiation. In addition, local workplace environmental conditions such as local heat sources, physical workload related metabolic heat production within the human body, and clothing properties, all affect the exchange of heat between the body and the environment. A robust occupational heat stress and heat strain index should properly address all these factors. This article reviews and highlights a number of selected indices, indicating their strengths and weaknesses in relation to meteorological data, local workplace environments, body heat production and the use of protective clothing. These heat stress and heat strain indices include Wet Bulb Globe Temperature, Discomfort Index, Predicted Heat Strain index, and Universal Thermal Climate Index. Relevant preventive strategies for alleviating heat strain are proposed.

More and more people will experience thermal stress in the future as the global temperature is increasing at an alarming rate and the risk for extreme weather events is growing. The increased exposure to extreme weather events poses a challenge for societies around the world. This literature review investigates the feasibility of making advanced human thermal models in connection with meteorological data publicly available for more versatile practices and a wider population. By providing society and individuals with personalized heat and cold stress warnings, coping advice and educational purposes, the risks of thermal stress can effectively be reduced. One interesting approach is to use weather station data as input for the wet bulb globe temperature heat stress index, human heat balance models, and wind chill index to assess heat and cold stress. This review explores the advantages and challenges of this approach for the ongoing EU project ClimApp where more advanced models may provide society with warnings on an individual basis for different thermal environments such as tropical heat or polar cold. The biggest challenges identified are properly assessing mean radiant temperature, microclimate weather data availability, integration and continuity of different thermal models, and further model validation for vulnerable groups.

The aim of the study was to examine the various design features of ventilated garments on cooling performance. Five jackets with small ventilation units and closable openings were designed. The ventilation units with a flow rate of 12 l/s were placed at five different torso sites. They were examined on a sweating thermal manikin in four clothing opening conditions in a warm environment ( T a = T manikin = 34 °C, RH = 60%, V a = 0.4 m/s). Total torso cooling was increased by 137–251%, and clothing total dynamic evaporative resistance was decreased by 43–69%. Neither the ventilation location nor the opening design had a significant difference on total torso cooling. The ventilation location had a significant difference on localized intra-torso cooling, but not the opening design. When the ventilation units were placed at the local zone where it was ventilated, that zone underwent the highest cooling than other local zones. The study indicated that the ventilation units should be placed at the region where it required the most evaporative cooling, e.g. along the spine area and the lower back. The openings could be adjusted (closed or opened) to make comfortable air pressure for the wearers but without making significant difference on the whole torso cooling under this flow rate. Relevance to industry Heat strain is frequently reported in hot environments, especially for those industries, such as construction, mining and steel. Clothing equipped with the small ventilation units could circulate the ambient air around the body and thus decrease heat strain and improve productivity.

In this study, we validated comfort and limit temperatures of four sleeping bags with different levels of insulation defined according to EN 13537. Six male subjects and four female subjects underwent totally 20 two-hour exposures in four sleeping bags at four intended testing temperatures: 11.2, 3.8, 2.1 and -9.0 degrees C. The subjective perceptions and physiological responses of these subjects were reported and analyzed. It was found that the EN 13537 defined comfort temperature and limit temperature were underestimated for sleeping bags MA3, HAG and MAM. The predictions are so conservative that further revision may be required to meet the requirements of both manufacturers and consumers. In contrast, for the sleeping bag MAO with a low level of insulation, the limit temperature defined by EN 13537 was slightly overestimated. In addition, two individual case studies (-28.0 and -32.0 degrees C) demonstrated that low toe temperatures were widely observed among the male and female subjects, although the mean skin temperatures were almost within the thermoneutrality range (32.0-34.0 degrees C). It seems that the IREQ model (ISO 11079) overestimated both the comfort and limit temperatures of the sleeping bags. Finally, traditional sleeping bags may be required to be re-designed to provide consumers both whole body comfort as well as local thermal comfort at feet/toes or users need to be made aware of the higher need for their insulation. (C) 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved. (Less)

Stair ascending performance is critical during evacuation from buildings and underground infrastructures. Healthy subjects performed self-paced ascent in three settings: 13 floor building, 31 floor building, 33 m stationary subway escalator. To investigate leg muscle and cardiorespiratory capacities and how they constrain performance, oxygen uptake (VO 2 ), heart rate (HR) and ascending speed were measured in all three; electromyography (EMG) in the first two. The VO 2 and HR ranged from 89 to 96% of the maximum capacity reported in the literature. The average highest VO 2 and HR ranged from 39 to 41 mL·kg −1 ·min −1 and 162 to 174 b·min −1 , respectively. The subjects were able to sustain their initial preferred maximum pace for a short duration, while the average step rate was 92–95 steps·min −1 . In average, VO 2 reached relatively stable values at ≈37 mL·kg −1 ·min −1 . EMG amplitudes decreased significantly and frequencies were unchanged. Speed reductions indicate that climbing capacity declined in the process of fatigue development. In the two buildings, the reduction of muscle power allowed the subjects to extend their tolerance and complete ascents in the 48 m and 109 m high stairways in 2.9 and 7.8 min, respectively. Muscle activity interpretation squares were developed and proved advantageous to observe fatigue and recovery over time.

Owing to giving more stable and repeatable test results than human tests, thermal manikin is widely used in fields like clothing, automobile, building, aerospace, etc. Thermal manikin is promising and reliable to characterize both static and dynamic heat and moisture exchange in human body-clothing-environment system, particularly in extremely hot or cold environments. Nowadays, there are hundreds of thermal manikins with different functions in the world and their functions become more and more humanlike, e.g., can better simulate human thermoregulations. In this chapter, we reviewed and concluded the types of manikin in terms of anthropometric data, number of the body segment, construction, function, feedback system, working principle, control mode, etc. The state of the art and future trends of the advanced tool were summarized. With the development of manufacture technology, computer science and signal processing capacity, a more humanlike simulator can predict physiological and psychological responses of human body in various conditions. It can make significant contribution in realistic performance evaluation for protective clothing in hazardous environments, as an alternative for human beings.

Five protective garments (light summer clothing L, high visibility clothing HV, military clothing MIL, climber coverall CLM and firefighting clothing FIRE) were assessed on eight unac- climated male subjects at two environments: moderate warm environment with high humidity (MWH, 20.0°C, 86% relative humidity) and warm environment with moderate humidity (WMH, 30.0°C, 47% relative humidity). The thermophysiological responses and subjective sensations were reported. The PHS model (ISO7933) was used for predicting thermophysiological responses for each testing scenario. It was found that there were significant differences between clothing FIRE and other clothing on thermal sensation (p

Cooling vests incorporated with phase change materials (PCMs) add extra insulation and restrict sweat evaporation. It is still unclear how much cooling benefit they can provide. The aim of this study was to investigate the torso cooling of the PCM vests in two hot environments: hot humid (HH, 34°C, 75% relative humidity (RH)) and hot dry (HD, 34°C, 37% RH). A pre-wetted torso fabric skin was used to simulate torso sweating on a thermal manikin. Three cooling vests incorporated with three melting temperatures ( Tm) of PCMs were tested ( Tm = 21°C, Tm = 24°C and Tm = 28°C). They were worn under a military ensemble (total thermal insulation 1.60 clo; evaporative resistance 0.0516 kPaċm2/W), respectively. In a HH environment all the three cooling vests provided effective torso cooling; in a HD environment the cooling benefit was negative. In both environmental conditions, the evaporative cooling was greatly restricted by the cooling vests. The study indicated that when wearing the protective clothing with the relatively low evaporative resistance and when sweat production was high, the cooling vests were effective in a HH environment, but not in a HD environment.