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Article

Experimental Investigation into the Thermal Performance of Personal Cooling Mechanisms

by
Miriam Martinez-Albert
1,
Pablo Díaz-García
2,
Ignacio Montava-Seguí
2 and
Eva Bou-Belda
2,*
1
Textile Industry Research Association-AITEX, Comfort Department, Carretera de Bañeres, No 10, 03802 Alcoy, Spain
2
Departamento de Ingeniería Textil y Papelera, Escuela Politécnica Superior de Alcoy, Universitat Politècnica de València, PI. Ferrándiz Carbonell, s/n, 03801 Alcoy, Spain
*
Author to whom correspondence should be addressed.
Appl. Sci. 2025, 15(6), 3296; https://doi.org/10.3390/app15063296
Submission received: 19 February 2025 / Revised: 12 March 2025 / Accepted: 13 March 2025 / Published: 18 March 2025
(This article belongs to the Section Applied Thermal Engineering)
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Abstract

:
Environmental conditions, job tasks, and clothing choices influence the thermal comfort of workers. While it is impossible to control outdoor environmental conditions, selecting appropriate clothing for workers is feasible. Personal protective equipment often does not completely protect outdoor workers at high air temperatures. In such cases, cooling garments can help dissipate body heat and be worn with standard work clothes or uniforms. Currently, there is a lack of consensus in the literature regarding the characterisation of this type of garment. This study employed an innovative laboratory testing method that integrates a thermal manikin with a computer simulation program to assess the thermal sensation and comfort of various garment types in different activities and environmental conditions. This advanced approach enables a thorough evaluation of cooling garments that considers their physical properties and interactions with the human body. The findings confirm the efficacy of the tested cooling mechanisms, highlighting that the air circulation mechanism was the only one that consistently maintained user comfort across low, medium, and high metabolic activity levels. This study aims to assist users in selecting the most suitable cooling mechanism for the market based on the type of work or activity being performed.

1. Introduction

The heat balance equation [1] indicates that the body achieves thermal equilibrium by balancing internal heat production with heat exchange during the respiratory process and through the skin. In the respiratory system, heat exchange mainly occurs through convection and evaporation. Heat exchange occurs via convection, evaporation, conduction, and radiation for the skin. The body’s heat loss in hot environments is primarily through evaporative heat exchange [2]. This process involves the transfer of heat from the body to water on the skin, leading to the conversion of water into water vapour, which then disperses into the surrounding environment. Heat exposure affects the thermoregulation of the person [3] because heat transfer can be compromised in this environment. A person’s core temperature is between 37.0 and 37.5 °C [4], with a mean skin temperature of around 32.0–34.0 °C [5]. In hot conditions, with an air temperature above 33.0 °C, the core temperature can be increased because sweat evaporation can be compromised, leading to heat stress [6]. This can significantly impact a person’s cognitive response and ability, especially during complex work or activities [7].
It is alarming that one-third of heat-related deaths over the past 30 years can be attributed to climate change [8]. The Copernicus Climate Change Service (C3S) [9] has confirmed that the last decade has been the warmest period, with 2023 and 2024 marking the highest temperatures. Projections indicate an average surface warming increase of +2.7 °C by the end of the 21st century, which could lead to a staggering 370% rise in heat-related fatalities due to intensified heatwaves. The 2024 report from the Lancet Countdown on Health and Climate Change [10] reveals that 2024 was the hottest year since 1850, with a global average air temperature of 15.10 °C, an increase of +0.12 °C compared to the previous record holder, 2023. Moreover, 2024 is the first year recorded with a worldwide air temperature exceeding 1.5 °C above pre-industrial levels, surpassing the internationally agreed target set at the UN Climate Change Conference (COP21) in Paris [11], with a notable increase of 1.60 °C. This highlights the urgent necessity for effective cooling mechanisms to mitigate the impact of climate change on human health, and our study represents a crucial effort toward addressing this pressing need.
Employees who work outside are at a higher risk of experiencing thermal stress in severe weather conditions, as these conditions cannot be controlled. How outdoor workers perceive temperature affects the heat exchange between their bodies and the environment as well as their physiological and psychological well-being. To safeguard outdoor workers from such environmental conditions, the primary strategy is to prevent exposure to extreme conditions or to provide them with Personal Protective Equipment. The certification standards for protective clothing in cold environments include the EN 342-2017 [12] standard for ensembles and garments designed for protection against cold and the EN 14058-2017 [13] standard for garments intended for use in cool environments. Currently, there are no standards for protective garments in hot environments, so workers exposed to hot outdoor conditions may not have appropriate personal protective equipment to mitigate this risk, and they are unsafe.
Understanding the role of clothing in maintaining the thermal comfort of outdoor workers is crucial. In heat-stress environments, it is essential for clothing to facilitate the evaporation of moisture from the skin, thereby maintaining thermal comfort and preventing heat stress. The materials and fabrics of PPE need to be breathable, allowing for the efficient passage of sweat from the user’s skin to the environment. Additionally, cooling garments that can be used with personal protective clothing can aid users in maintaining thermal comfort under heat stress conditions by reducing core and mean skin temperature and minimising sweat production [14].

1.1. Personal Cooling Systems

From 2001 until the end of 2024, around 315 scientific publications have been dedicated to personal cooling systems, including vests and garments. This total includes 136 publications on cooling vests, 138 on cooling clothes in general, and 41 on personal cooling systems. Notably, 2023 and 2024 recorded the highest number of publications within this timeframe. Various cooling garments are available on the market, but most scientific journal studies have focused on cooling vests. This is because the torso is the most sensitive part of the body to temperature [15], and in terms of ergonomics, vests are more accessible to wear than a full suit.
Selecting the most appropriate cooling vest for a particular activity and environment can be challenging, given the variety of cooling mechanisms available and the often limited information regarding their performance for end users. Different cooling garments employ diverse heat-dissipating mechanisms, and literature suggests they are effective when their cooling capacity ranges from 165 to 540 W [16]. However, the effectiveness of many of these products has not been thoroughly verified. As a result, some items are labelled as cooling garments without a comprehensive understanding of the level of thermal comfort they provide to the wearer. Each cooling mechanism presents its advantages and disadvantages, and the choice of which to use ultimately depends on factors such as the intended application, ergonomics, and weight. The market offers various cooling vests that differ in their cooling mechanism to dissipate body heat [17]:
  • Cooling Water Circulation Vest: This cooling vest uses cool water to dissipate body heat by the physical parameter of conduction of the cold water.
  • Air cooling vest: This cooling technique uses convection and sweat evaporation due to air circulation generated by fans.
  • Phase-change material cooling vest: This cooling mechanism utilises microcapsules that can change from solid to liquid to remove heat from the user’s body.
  • Water evaporation vest: This vest utilises a simple cooling technique, which is the evaporation of water to reduce body heat.
  • Hybrid cooling vest: This innovative vest integrates multiple cooling techniques into a single design. For instance, it may feature a combination of phase change materials (PCMs) alongside fans to enhance air circulation or blend water evaporation methods with PCMs for effective cooling.

1.2. Methods for Characterisation of Cooling Garments

In the literature, various testing methods are utilised to characterise cooling garments. These methods include mathematical calculation models or standardised test methods such as ASTM F2371-24 [18], which employs a thermal manikin, and the standard ASTM F2300-22 [19], which involves human subjects. The following section describes the methods used for characterising cooling garments:
  • Thermophysiological prediction models: Thermophysiological comfort models can be categorised into single-node, two-node, and multi-node models, depending on how the body is divided for simulation purposes. The single-node predictive model considers the complete body, while the two-node and multi-node models break the body into different parts [20]. Fanger’s PMV (Predicted Mean Vote) model was the first classical single-node thermal comfort model [21]. This model is based on a combination of physical environmental factors and human physiological factors, establishing a linear relationship between mean skin temperature, perspiration rate, and activity intensity, but it applies only under uniform conditions. In the two-node model, which simplifies the human body into two layers, skin and core, the most used comfort model is from Gagge et al. [22]. Multi-node models include the Stolwijk model [23], which is designed only for steady-state conditions, and the Tanabe et al. [24] model, which applies to steady-state, transient, and non-uniform conditions. Several recent models have enhanced existing frameworks, such as the JOS-2 [25] and JOS-3 [26], which build upon the foundational Tanabe model. Furthermore, notable improvements have been made to the Stolwijk model, including integrating the Fiala et al. model [27,28] and the UC Berkeley Thermophysiological Comfort model [29,30]. Another thermoregulation model, THERMODE 23 (Thermoregulation Model for Disuniform Environments) [31], was recently introduced. This model thoughtfully incorporates the latest advancements in both active and passive systems, as well as advancements in the modelling of thermal sensation. The use of thermophysiological models provides quick results and allows the assessment of various combinations using estimated data to predict human thermal responses. However, a limitation of these models is that they yield simulations rather than precise measurements, and exceptions must be considered such as the type of activity, age, and race, among other parameters.
  • Standard method according to ASTM F2371-24: This testing method uses a thermal manikin to evaluate the cooling power and duration of a cooling vest. It measures the heat needed to maintain the mean skin temperature of the manikin, but it does not assess thermophysiological parameters.
  • Standard method according to ASTM F2300-22: This method involves conducting tests with individuals to understand their physiological responses, comfort levels, and thermal sensations while wearing the garment. Additionally, specific test methods with human subjects have been developed by individual laboratories to suit the particular use of the garment; for instance, Tokizawa et al. [32] examined a vest with a fluid circulation system, while Lai and Wu [33] tested the thermal comfort of firefighting suits with different types of vests.

1.3. Individual Thermal Comfort and Sensation

Individuals’ thermal comfort and sensation are influenced by environmental factors such as air temperature, relative humidity, mean radiant temperature, air velocity, metabolic rate, and clothing [34]. Thermal comfort reflects a person’s contentment with the thermal environment, typically assessed through surveys and mathematical models. The thermal point scale that evaluates user comfort is measured using the Comfort Sensation Vote (CSV) following ISO 10551-19 [35], as shown in Table 1.
On the other hand, thermal sensation refers to the individual’s perception of the thermal environment. It is quantified using the standard ASHRAE 55-23 [36], outlining the conditions necessary for a satisfactory indoor environment in buildings and other occupied spaces. This standard specifies the environmental conditions, including air temperature, relative humidity, air velocity, mean radiant temperature of surrounding walls and objects, activity level of occupants, and clothing type. The standard uses the PMV (Predicted Mean Vote) and PPD (Predicted Percentage Dissatisfied) calculations based on the ISO 7730-2005 standard [37] with the 7-point thermal sensation scale in Table 2, which is derived from the heat balance of the human body. The PMV is calculated using estimations of metabolic rate based on the type of work and thermal resistance of clothing.

2. Materials and Methods

2.1. Methodology

Thermal manikins assess heat loss, thermal insulation, and breathability by maintaining a consistent temperature setpoint and a specific sweat delivery rate. When combined with a thermophysiological predictive model, these manikins can estimate a user’s thermal comfort and sensation, two subjective parameters that usually require human testing, as well as other physiological factors such as mean skin temperature and core temperature. This study employs a thermal manikin and two thermophysiological prediction models to evaluate the thermal performance of four cooling mechanisms. The thermal performance is assessed based on the mean skin temperature, hypothalamus temperature, thermal comfort index, and thermal sensation index of the manikin wearing the different cooling garments.

2.2. Equipment

2.2.1. Thermal Manikin with Manikin PC Software

A thermal manikin with 34 segments from Thermetrics LLC. Seattle, WA, USA [38], shown in Figure 1, was used for this research. This manikin was made according to the ISO 15831-04 [39] and ASTM F2370-24 [40] standards. This manikin is equipped with a sweating system that allows it to simulate the perspiration system of a human in the body of the thermal manikin. The sweating system consists of a pump and tubes distributing water throughout the manikin’s body. In this case, the manikin was dressed in a second-skin suit that becomes wet upon contact with water, simulating a user’s skin.
Coupled with the thermal manikin, the Manikin PC Software from Thermoanalytical Inc. Calumet, MI, USA [41] was used to simulate a person’s thermoregulatory system within a thermal manikin. The software is based on the thermophysiological predictive models developed by Fiala and Berkeley. This software has been validated in multiple studies before commercialisation [42,43,44], demonstrating a strong correlation between the responses of the Newton thermal manikin and those of human subjects.

2.2.2. Climatic Chamber

During the tests, the thermal manikin was placed inside a WalkIn Model climatic chamber that measured 14 m in length, 3 m in width, and 5 m in height. This climatic chamber can be used at air temperatures ranging from −30.0 °C to +60.0 °C, with a relative humidity range of 30% to 90% and an air velocity of 12 m/s.

2.3. Experimental Procedure

2.3.1. Testing Samples

Testing samples used in this study and their characteristics are presented in Table 3.
Due to the thermal manikin measurements, vests tested were size M. All vests had a central zipper from the low part to the upper part of the vest to close the garment around the manikin. We focused on measuring only the torso area of the manikin, as this is the specific region covered by the vest. This area can be seen in Figure 2 and encompasses the upper chest, stomach, waist, shoulders, mid-back and lower back.

2.3.2. Testing Protocol

The testing method used for this evaluation was based on a new testing protocol developed to evaluate cooling systems [45]. This test method was successfully compared with the data generated following the ASTM F2371 standard for low, moderate and high metabolic rates of activity. The parameters evaluated in this study to assess the performance of the different cooling mechanisms were:
  • Local skin temperature (Tsk): Taken directly from each region of the manikin and calculated from the model. In this case, it was the mean skin temperature of the torso region.
  • Hypothalamus temperature (Thy): The hypothalamus temperature is the most representative of cardiac and brain temperature and represents the core temperature measurement in this software. The hypothalamus is the centre of our body’s thermoregulation and controls our internal temperature, activating, for example, evaporation in case of an increase in our core temperature, so it is an essential parameter to evaluate the thermal comfort of the body.
  • Thermal comfort index: According to a 7-point scale from −3 (very uncomfortable) to 3 (very comfortable) from the ISO 10551-19 standard.
  • Thermal sensation index: According to the ASHRAE-55-2023 standard with a 7-point scale ranging from −3 (cold) to 3 (hot).
The environmental conditions used were the same as those used for the ASTM F2371-24 and ASTM F2300-22 standards. The climatic chamber was set to an air temperature of 35.0 ± 0.5 °C, a relative humidity of 40 ± 5%, and an air velocity of 0.4 ± 0.1 m/s. The manikin was placed in the centre of the climate chamber, wearing the sweating system.
At the start of each test, we needed the manikin to be in a thermoneutral state, with a mean skin temperature of 34.4 °C throughout the body and a hypothalamus temperature of 37.0 °C. The manikin achieved this thermoneutral state using the software option “thermoneutral state”. This preliminary test ensures that the manikin is in the same neutral state before each test. Upon completing this baseline assessment, the manikin was outfitted with different cooling vests and subjected to the identical testing protocol.
Some vests need preliminary preparation before dressing the manikin with the samples for testing to ensure that the cooling mechanisms are working:
  • Cooling vest 1: charge the battery and fill the reservoir with water.
  • Cooling vest 2: charge the battery.
  • Cooling vest 3: immerse in water and drain.
  • Cooling vest 4: Place the PCM packs in a freezer at −50.0 °C for 40 min.
The data obtained from the software are affected by several factors, including environmental conditions, the sample being analysed, the simulated activity, and its duration. Therefore, the only parameter we needed to input into the software to evaluate the thermal performance of the samples was the metabolic rate of the activity we wanted to simulate. Table 4 shows activity levels and their metabolic rates according to ISO 8996-2021 [46], with the equivalence of the metabolic rate in different units. The metabolic rate in the software is displayed in Metabolic Equivalent of Task Units (met), where 1 met corresponds to 58.2 W/m2.
In this evaluation, the performance of the cooling vests was assessed across three different activity levels: low metabolic rate (1.4 met), moderate metabolic rate (2.8 met), and high metabolic rate (4.0 met). Each activity was simulated for 20 min, starting with the lowest metabolic rate and finishing with the highest. Before dressing the manikin in the different cooling vests, a baseline test was conducted without any sample, with the manikin nude, to compare the measurements with those wearing the tested cooling vests.

3. Results

3.1. Mean Skin Temperature of Torso Zone

Table 5 presents the mean skin temperature of the trunk of the manikin wearing the different vests and the result for the nude manikin (TSk).
Figure 3 compares the manikin’s mean skin temperature wearing the tested samples across different metabolic rates.

3.2. Hypothalamus Temperature

Table 6 presents the hypothalamus temperature measured in the manikin in all tests.
Figure 4 compares the hypothalamus temperature of the manikin nude and the manikin wearing the tested samples with different activities.

3.3. Thermal Sensation Index

Table 7 displays the thermal sensation index achieved while testing the different cooling vests.
In Figure 5, the thermal sensation index of the tested samples is compared.

3.4. Thermal Comfort Index

Table 8 displays the thermal comfort index of the manikin nude and wearing the different cooling vests.
The thermal comfort index results and the comparison between samples are illustrated in Figure 6, which reveals the levels of thermal comfort experienced by the nude manikin and the manikin wearing different cooling vests across different activity levels.

4. Discussion

According to the results of mean skin temperature, it was noted that during low-energy activities, the mean skin temperature of the manikin when wearing various cooling vests tended to be lower than that of the manikin without a vest. This suggests that the different cooling mechanisms effectively contribute to decreasing the manikin’s mean skin temperature during this level of activity. As the activity level escalated to moderate metabolic activity, the manikin wearing different cooling vests displayed lower mean skin temperatures than the nude manikin, except when wearing cooling vest 4, which utilises phase change materials (PCMs). However, during high metabolic rate activity, only when wearing cooling vest 2, which employs an air-cooling mechanism, did the manikin demonstrate lower mean skin temperatures.
The hypothalamus temperature range, indicative of thermal comfort for individuals, is typically between 36.1 °C and 37.1 °C. When assessing the effectiveness of various cooling vests, it was observed that during low-energy activities, the initial mean skin temperature of the manikin fell within this range, suggesting a state of thermal comfort. However, as the activity level increased to a moderate metabolic rate, the hypothalamus temperature of the nude manikin rose to 38.1 °C, like the temperature observed in the manikin wearing cooling vest 4, the vest with PCMs, implying limitations in effectively lowering core temperatures. Conversely, with the same activity level, the manikin wearing the cool water circulation vest, the air-cooling vest, or the water evaporation cooling vest maintained a hypothalamus temperature of 36.9 °C, indicating thermal comfort. During high metabolic rate activity, the manikin wearing cooling vest 2, the air circulation vest, exhibited the lowest hypothalamus temperature of 37.1 °C, the only vest with an adequate thermal comfort at this level.
The thermal sensation is associated with the mean skin temperature and hypothalamus temperature. At low activity levels, the manikin wearing the cooling vests had better thermal sensation than the nude manikin, suggesting that all the cooling vests effectively improved the manikin’s thermal sensation. As the activity level increased to a moderate metabolic rate, the thermal sensation of the manikin wearing the different cooling mechanisms remained better than that of the manikin without any vest, except for the manikin wearing cooling vest 4, the PCM vest. This indicates that this cooling vest could only improve the thermal sensation of the manikin at low-energy activities. After conducting high metabolic rate activities, it was observed that only the manikin wearing vest 2, the air-cooling vest, had improved thermal sensation. This indicates that the air-cooling vest effectively enhanced the manikin’s thermal sensation during low, moderate, and high activity levels.
The results regarding the thermal comfort index indicate a direct relationship between mean skin temperature, hypothalamus temperature, and thermal sensation. The nude manikin was found to be slightly uncomfortable. In contrast, the manikin wearing various cooling vests demonstrated improved thermal comfort, especially at low activity levels, as reflected in thermal sensation measurements. The cool water circulation vest, air circulation vest, and evaporation vest enhanced thermal comfort compared to the nude manikin and the PCM vest during moderate activity levels. However, at high energy activity levels, only the air circulation vest significantly improved the thermal comfort of the manikin.

Limitations and Future Considerations

The conclusions drawn from this study are based exclusively on thermal perception under specific environmental conditions of 35 °C of air temperature, 40% relative humidity, and an air velocity of 0.4 m/s, which simulate a hot dry environment. This setup was selected to compare the results obtained from this testing method with those defined in the ASTM F2371-24 and ASTM F2300-22 standards. Under these conditions, a favourable relative humidity gradient was established between the manikin’s skin and the surrounding air in the hot-dry environment. Future research will implement the same in-house testing protocol under varying relative humidity levels to validate further cooling vests’ performance in different hot environmental scenarios.

5. Conclusions

Based on the results, the air circulation vest is highly recommended for use during low, moderate, and high metabolic rate activities. It maintained a neutral comfort state for the manikin, providing a consistent sense of comfort across all three activity levels, with cooling duration dependent on battery life. In contrast, the cool water circulation and evaporative vest are recommended for low- to moderate-workload activities. The evaporative vest would be particularly suitable for situations requiring a brief cooling sensation. In contrast, the cool water circulation vest would be better suited for prolonged cooling due to its reliance on battery duration. The findings of this study indicate that the cooling mechanism of phase change materials (PCM) could be effectively utilised for activities involving low metabolic energy expenditure, such as sitting or standing, and for short durations of up to 20 min.
In conclusion, while all the cooling vests evaluated in this study could enhance the user’s thermal sensation and comfort, the choice of cooling mechanism should align with the type and duration of the activity. The air circulation vest would be optimal for light, moderate, and high activity levels; the cool water circulation and evaporative vests would be appropriate for light and moderate activities; and the PCM vest would be best suited for light activities.

Author Contributions

Conceptualization, M.M.-A. and E.B.-B.; methodology, M.M.-A. and E.B.-B.; formal analysis, M.M.-A. and E.B.-B.; investigation, all authors; resources, all authors; writing—original draft preparation, M.M.-A.; writing—review and editing, M.M.-A. and E.B.-B.; supervision, E.B.-B., P.D.-G. and I.M.-S. All authors have read and agreed to the published version of the manuscript.

Funding

Funding for open access charge: CRUE-Universitat Politècnica de València.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Data are available on request due to restrictions.

Acknowledgments

The authors would like to express their gratitude for the support of the Universitat Politècnica de València. Funding for open access charge: Universitat Politècnica de València.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. Thermal manikin.
Figure 1. Thermal manikin.
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Figure 2. The trunk of the manikin.
Figure 2. The trunk of the manikin.
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Figure 3. Comparison of mean skin temperature across different metabolic rates.
Figure 3. Comparison of mean skin temperature across different metabolic rates.
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Figure 4. Comparison of hypothalamus temperature across different metabolic rates.
Figure 4. Comparison of hypothalamus temperature across different metabolic rates.
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Figure 5. Comparison of thermal sensation index across different metabolic rates.
Figure 5. Comparison of thermal sensation index across different metabolic rates.
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Figure 6. Comparison of the thermal comfort index across different metabolic rates.
Figure 6. Comparison of the thermal comfort index across different metabolic rates.
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Table 1. Seven-point thermal comfort scale per the standard ISO 10551-19.
Table 1. Seven-point thermal comfort scale per the standard ISO 10551-19.
LevelThermal Comfort
−3Very uncomfortable
−2Uncomfortable
−1Slightly uncomfortable
0Neutral
1Slightly comfortable
2Comfortable
3Very comfortable
Table 2. Seven-point thermal sensation scale per standard ASHRAE 55-23.
Table 2. Seven-point thermal sensation scale per standard ASHRAE 55-23.
LevelThermal Sensation
−3Cold
−2Cool
−1Slightly cool
0Neutral
1Slightly warm
2Warm
3Hot
Table 3. Cooling vests were used in this study.
Table 3. Cooling vests were used in this study.
Cooling VestCooling MechanismAccessories
1Cooling water circulation Pump, cooling system, battery
2Air circulationBattery
3Water evaporation---
4PCMs (28 °C)PCM packs
Table 4. Classification of ranges of metabolic rate according to ISO 8996-21 standard and equivalences between units.
Table 4. Classification of ranges of metabolic rate according to ISO 8996-21 standard and equivalences between units.
Activity LevelRange of Metabolic
Rate (W)		Range of Metabolic
Rate (W/m2)		Range of Metabolic
Rate (met)
Resting100–12555–691.0–1.2
Low metabolic rate125–23569–1301.2–2.2
Moderate metabolic rate235–360130–2002.2–3.4
High metabolic rate360–465250–2583.4–4.4
Table 5. Results of mean skin temperature (TSk).
Table 5. Results of mean skin temperature (TSk).
Samples TestedMean Skin Temperature TSk (°C ± 0.1 °C)
1.4 met2.8 met4.0 met
Nude manikin35.336.037.0
Vest 133.434.937.0
Vest 234.335.236.5
Vest 334.635.337.0
Vest 434.636.037.0
Table 6. Results of hypothalamus temperature (Thy).
Table 6. Results of hypothalamus temperature (Thy).
Samples TestedHypothalamus Temperature Thy (°C ± 0.1 °C)
1.4 met2.8 met4.0 met
Nude manikin37.038.138.4
Vest 136.936.937.5
Vest 236.936.937.1
Vest 336.936.937.5
Vest 436.938.138.4
Table 7. Results of thermal sensation index.
Table 7. Results of thermal sensation index.
Samples TestedThermal Sensation Index
1.4 met2.8 met4.0 met
Nude manikin111
Vest 1001
Vest 2000
Vest 3001
Vest 4011
Table 8. Results of thermal comfort index.
Table 8. Results of thermal comfort index.
Samples TestedThermal Comfort Index
1.4 met2.8 met4.0 met
Nude manikin−1−1−1
Vest 111−1
Vest 2110
Vest 311−1
Vest 41−1−1
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Martinez-Albert, M.; Díaz-García, P.; Montava-Seguí, I.; Bou-Belda, E. Experimental Investigation into the Thermal Performance of Personal Cooling Mechanisms. Appl. Sci. 2025, 15, 3296. https://doi.org/10.3390/app15063296

AMA Style

Martinez-Albert M, Díaz-García P, Montava-Seguí I, Bou-Belda E. Experimental Investigation into the Thermal Performance of Personal Cooling Mechanisms. Applied Sciences. 2025; 15(6):3296. https://doi.org/10.3390/app15063296

Chicago/Turabian Style

Martinez-Albert, Miriam, Pablo Díaz-García, Ignacio Montava-Seguí, and Eva Bou-Belda. 2025. "Experimental Investigation into the Thermal Performance of Personal Cooling Mechanisms" Applied Sciences 15, no. 6: 3296. https://doi.org/10.3390/app15063296

APA Style

Martinez-Albert, M., Díaz-García, P., Montava-Seguí, I., & Bou-Belda, E. (2025). Experimental Investigation into the Thermal Performance of Personal Cooling Mechanisms. Applied Sciences, 15(6), 3296. https://doi.org/10.3390/app15063296

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