Article

Thermophysiological Comfort Properties of Ripstop Fabrics for Enforcement Personnel Clothing

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Abstract

The choice of fabric parameters such as fiber type and structure play a key role in the thermoregulatory process as they can determine the change and loss of heat and moisture through sweat evaporation and heat dissipation. In this paper, the thermophysiological comfort properties of ripstop fabrics with different material composition percentages of polyester/cotton (P50C50 and P35C65) and nylon/cotton (N50C50 and N20C80) are reported. The study focuses on the fabric's air permeability, thermal resistance and water vapour resistance. The results suggest that the air permeability of the fabrics depends on thread density. Fabrics with the lowest thread densit y (P50C50) have a more open structure and therefore allow more air to pass through it. The results also indicate that the fibre content affects the thermal resistance of the fabrics. Fabrics with lower proportion of cotton, P50C50 and N50C50, show lower thermal resistance results. With regards to water vapour resistance, fabrics containing nylon fibres (N20C80 and N50C50) gave higher resistance in comparisons with fabrics containing polyester (P35C65 and P50C50). The opposite trend was seen with water vapour permeability results. Overall, fabric of P50C50 gave the best thermophysiological comfort properties as indicated from the study.

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... The chosen materials are fabrics that are currently used for enforcement personnel clothing which were obtained from the Science and Technology Research Institute for Defense (STRIDE). Two materials were chosen as a follow-up from a previous study on the study of thermophysiological properties [18]. A code was given to each fabric; the first and second letters are abbreviations of the first and second fibres, and the number represents the percentage of fiber content, as indicated in Table 1. ...
... The results are consistent throughout the test for all participants. These responses correspond to the comfort properties of the N20C80 fabric, which had lower water vapour permeability, lower air permeability and poor one-way transport index (AOTI) properties compared to the P50C50 fabric [18]. Thus, the heat is not being transferred to the outer environment, and this trapped heat affects the participant's RPE. ...
... It showed that the heat was entrapped in the micro-environment of the N20C80 clothing. These results are interrelated to the thermophysiological findings which suggested that the N20C80 had lower water vapour permeability, lower air permeability and poor AOTI properties [18]. Respondents rate the sweating sensation for N20C80 as moderate sweating but heavy sweating for P50C50. ...
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Influence of Fabric Parameters on Thermal Comfort Performance of Double Layer Knitted Interlock Fabrics
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Assessing the Comfort of Woven Fabrics: Thermal Properties
  • B K Behera
  • P K Hari
B. K. Behera and P. K. Hari, "Assessing the Comfort of Woven Fabrics: Thermal Properties," Woven Text. Struct., pp. 330-342, 2010.