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Water vapor trapped in the boundary layer between a person and the clothing creates discomfort and other unpleasant sensations. When that water vapor is prevented from leaving the clothing by external vapor barriers or impermeable layers, those psychophysical states are further exacerbated. One situation where that can be problematic is in office workplaces, and the seats that workers use for many hours every day. This study aims to evaluate the impact of different fabrics that are used for seat cover on water vapor retention.

The authors' method determines the behavior of contact surface humidity with a 50 kg sandbag on the seat to mimic the deformation of the seat materials due to the seated person's weight. Thus, the maximum increase in relative humidity (RH) after humidification of the seat surface (ΔRH-max), the time required to reach the maximum value of humidity (t-max) and the time constant (TC) after humidity starts to fall were derived.

Of the three different seat covers tested, the ΔRH-max of the wool were 7.3–8.8%, compared to 27.0–29.0% of the polyvinyl chloride (PVC), indicating more moisture absorption and transmission of the wool. The TC of the acrylic cover was 224–384 min compared to the 483–558 min of the PVC, which indicated a quick drying out feature of the acrylic.

The ΔRH-max, t-max and TC were all significantly correlated with the RH at the back thigh skin surface of the actual human participants.

The purpose of this paper is to provide the details of developments to researchers in test apparatus and evaluation methods to rate the thermal protective performance (TPP) of firefighters’ clothing under high-temperature and high-humidity condition.

This review paper describes the influence laws of moisture on thermal protection and the moisture distribution in actual fire environment. Different evaluation methods used for assessing the effect of moisture on the TPP were investigated, with an emphasis on test devices, evaluation indexes as well as their relationship and limitations.

The moisture from the ambient, clothing and human perspiration plays an important role in determining the TPP of firefighter protective clothing. It is obvious that research on moisture-driven heat transfer in firefighter’s clothing system are comparatively little, primarily focussing on pre-wetted methods of multi-layer fabric. Further studies should be conducted to develop more standardized moistening systems and improve the current calculation methods for evaluating the performance of protective clothing. New explorations for heat and moisture transfer mechanism in protective clothing should be investigated.

Protective clothing is the efficient way to provide fire-fighting occupational safety. To accurately evaluate the TPP of protective clothing under high-temperature and high-humidity condition will help to optimize the clothing performance and choose the proper clothing for providing firefighters with the best protection under multiple thermal hazards.

This paper is offered as a concise reference for scientific community further research in the area of the TPP evaluation methods under high-temperature and high-humidity condition.

The purpose of this study was to investigate the psychological response to changes in temperature and humidity near the skin, and the psychological factors of thermal discomfort.

The experiments involved changing the temperature and humidity from a neutral to a hot-humid environment, and vice versa, every 30 min. The psychological response to temperature (which ranged from 24 to 40°C) and humidity (which ranged from 30 to 80% relative humidity) was investigated.

The sensory scores shifted according to the direction of the change in temperature and humidity. The environment seemed to be evaluated relatively, whereby the sensory perception was dependent on the prior thermal environment. The psychological response to changes in temperature and humidity near the skin tended to shift from simple situational perceptions, such as feeling hot, to stifling and uncomfortable perceptions, and finally to the perception of dullness. Examining the psychological components revealed that the uncomfortable feeling was affected by “stifling” and “sweaty” perceptions with increasing temperature, by “stifling”, “sweaty”, and “sticky” perceptions with decreasing temperature, by “stifling”, “dull”, “sticky”, and “hot” perceptions with increasing humidity, and by “sweaty”, “dull”, and “humid” perceptions with decreasing humidity.

This study identified the psychological response that accompanies changes in temperature and humidity near the skin, as well as the psychological components of discomfort associated with changes in temperature and humidity. These results provide insights into the microclimate and thermal comfort of clothing.

The purpose of this paper is to study the combined effects of moisture and radiation on thermal protective performance of protective clothing exposed to low level radiation.

Using a sweating manikin, the effect of radiation and moisture on heat and moisture transfer was initially analyzed under the dry manikin with sweating rate of 100 g/(m2h) exposed to 2.5 kW/m2, and then studied at 200 and 300 g/(m2h) exposed to 2 and 3 kW/m2, respectively. Finally, the combined effects of thermal radiation and moisture were predicted by fitting the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity.

The results show that the heat loss and the wet skin surface temperature are affected by the combined effects of moisture and radiation, with two distinctly different trends. Heat loss from the manikin is increasing with the sweating rate, and decreasing with thermal radiation intensity. However, the wet skin surface temperature has an opposite situation.

Two filling equations are given to present the relationships among heat loss and wet skin surface temperature, with the sweating rate and radiation intensity. With these two equations, the heat loss and the wet skin surface temperature when exposed to radiation can be predicted by only measuring the mean radiant and ambient temperatures and controlling the sweating rate.

The purpose of this paper is to integrate a thermophysiological human body model into a CFD simulation to predict the dry and latent body heat loss, the clothing, skin and core temperature, skin wettedness and periphery blood flow distribution. The integration of the model allows to generate more realistic boundary conditions for the CFD simulation and allows to predict the room distribution of temperature and humidity originating from the occupants.

A two-dimensional thermophysiological body model is integrated into a CFD simulation to predict the interaction between the human body and room environment. Parameters varied were clothing insulation and metabolic activity and supply air temperature. The body dry and latent heat loss, skin wettedness, skin and core temperatures were predicted together with the room air temperature and humidity.

Clothing and metabolic activity were found to have different level of impact on the dry and latent heat loss. Heat loss was more strongly affected by changes in the metabolic rate than in the clothing insulation. Latent heat loss was found to exhibit much larger variations compared to dry heat loss due to the high latent heat potential of water.

Unlike similar studies featuring naked human body, clothing characteristics like sensible resistance and vapor permeability were accommodated into the present study. A method to ensure numerical stability of the integrated simulation was developed and implemented to produce robust and reliable simulation performance.

The purpose of the present study was to evaluate the effect of air mattress pressure on sleep quality.

Ten young healthy males participated in all hard surface [AH], shoulder soft [SS] and shoulder and hip soft mattress [SHS] conditions. The surface pressure for SS and SHS were set at their preferred levels.

The results showed that sleep efficiencies were over 95% for all the three conditions; there were no significant differences in individual sleep variables among the three conditions, but overall sleep quality was better for SS than AH (p = 0.065); heart rates during sleep was greater for AH than the other two conditions (p < 0.1); and a stronger relationship between clothing and bed microclimate humidity were found for SS and SHS than that for AH.

These results indicated that the both pressure relief air mattresses that were set at their own preferred levels provided high quality sleep with no marked differences.

Air pressure relief mattresses can improve sleep quality of healthy individuals during sleep at night. The results can be used to understand appropriate pressure distribution on surface mattress according to body region, and also to develop algorithms to provide optimum sleep using mattresses with surface pressure control by body region.

The present study found that the shoulder and/or hip pressure relief air mattresses that were set at their own preferred levels provided high quality sleep with no marked differences.

In this study, a novel dynamic testing method was established to measure the moisture variation of fabric surface during the process of moisture liberation in simulated windy condition. The paper aims to discuss these issues

In this method, the samples were rotating during the test process so as to simulate the external windy environment. Effects of simulated wind speed, moisture regains and fabric materials on the surface moisture of fabric were investigated.

Experimental results showed that the surface moisture presented a trapezoidal moisture liberation curve, it increased at first, then kept stable for a while, and decreased finally with the increase of time. It took longer time for the fabric to complete the liberation process when the moisture regain of the fabric increased or the simulated wind speed decreased. The fiber materials of the fabric affected the time for the moisture liberation process under a specific windy condition.

This study will benefit the designing and development of clothing such as sportswear.

A dynamic testing method was proposed to characterize the surface humidity of textiles under simulated windy conditions.

The purpose of this paper is to provide footwear designers, manikin builders and thermo‐physiological modellers with sweat distribution information for the human foot.

Independent research from two laboratories, using different techniques, is brought together to describe sweat production of the foot. In total, 32 individuals were studied. One laboratory used running at two intensities in males and females, and measured sweat with absorbents placed inside the shoe. The other used ventilated sweat capsules on a passive, nude foot, with sweating evaluated during passive heating and incremental exercise to fatigue.

Results from both laboratories are in agreement. Males secreted more than twice the volume of sweat produced by the females (p<0.01) at the same relative work rate. Both genders demonstrated a non‐uniform sweat distribution, though this was less variable in females. Highest local sweat rates were observed from the medial ankles (p<0.01). The dorsal foot sweated substantially more than the plantar (sole) areas (p<0.01). Sweating on the plantar side of the foot was uniform. Wearing shoes limited the increase in sweat production with increasing load, while the sweat rate of uncovered feet kept increasing with work and thermal load.

The observed variation in sweat rate across the foot shows that footwear design should follow the body mapping principle. Fabrics and materials with different properties can be used to improve comfort if applied to different foot surfaces. The data also demonstrate that foot models, whether physical (manikins) or mathematical, need to incorporate the observed variation across the foot to provide realistic simulation/testing of footwear.

We set up an original apparatus to measure the grain grain friction stress inside a granular medium composed of sodo‐silicate‐glass beads surrounded by a water vapor atmosphere.We analyze here the influence of the physico chemistry of water on our glass beads and its consequences on our shear experiment. We found two scales in the analysis of the shear stress signal. On the microscopic scale of one bead, the experimental results show a dependence on the size of beads, on the shear rate and on humidity for the resulting stick slip signal. On the macroscopic scale of the whole assembly of beads, the behavior of the total amplitude of the shear stress depends on the size of the beads and is humidity dependent only for relative humidity larger than 80%. For high degrees of humidity, on the microscopic scale, water lubricates the surface of the beads leading to a decrease in the microscopic resistance to shear while on the macroscopic scale the resistance to shear is increased: the assembly of very humid grains behaves as a rheothickening fluid.

The aim of this review is to present together the studies on textile-based moisture sensors developed using innovative technologies in recent years.

The integration levels of the sensors studied with the textile materials are changing. Some research teams have used a combination of printing and textile technologies to produce sensors, while a group of researchers have used traditional technologies such as weaving and embroidery. Others have taken advantage of new technologies such as electro-spinning, polymerization and other techniques. In this way, they tried to combine the good working efficiency of the sensors and the flexibility of the textile. All these approaches are presented in this article.

The presentation of the latest technologies used to develop textile sensors together will give researchers an idea about new studies that can be done on highly sensitive and efficient textile-based moisture sensor systems.

In this paper humidity sensors have been explained in terms of measuring principle as capacitive and resistive. Then, studies conducted in the last 20 years on the textile-based humidity sensors have been presented in detail. This is a comprehensive review study that presents the latest developments together in this area for researchers.