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Updated: Jul 26, 2026
05:20
Characterization of Thermal Transport in One-dimensional Solid Materials
Published on: January 26, 2014
Relationship between clothing ventilation and thermal insulation.
L M Bouskill1, G Havenith, K Kuklane
1Loughborough University, Human Thermal Environments Laboratory, Department of Human Sciences, Loughborough, LE11 3TU, UK.
Summary
Clothing ventilation significantly impacts thermal insulation by altering air exchange within the microenvironment. Ignoring ventilation can lead to inaccurate assessments of thermal stress for workers wearing protective ensembles.
Area of Science:
- Occupational health and safety
- Textile science
- Human thermal physiology
Background:
- Trapped air layers in clothing provide thermal insulation.
- Air exchange between clothing and the environment alters thermal properties.
- Current assessments often neglect clothing ventilation's impact on heat balance.
Purpose of the Study:
- To quantify the relationship between clothing ventilation and thermal insulation.
- To assess the impact of air exchange on thermal properties of different clothing layers.
- To highlight the importance of ventilation in thermal risk assessments.
Main Methods:
- Testing one-layer (air-impermeable) and three-layer (air-permeable) ensembles on an articulated thermal manikin.
- Controlled climate chamber experiments with varying manikin activity and environmental air speed.
- Measuring clothing ventilation (VT) and thermal insulation (Icl) under different conditions.
Main Results:
- Increased clothing ventilation (VT) reduced intrinsic insulation (Icl).
- Air exchange demonstrated significant heat exchange potential (up to 17 W/m2 for one-layer, 161 W/m2 for three-layer).
- Dynamic conditions (walking, increased air speed) substantially increased ventilation.
Conclusions:
- Clothing ventilation is a critical factor influencing thermal insulation.
- Ventilation significantly affects heat transfer and must be considered in thermal audits.
- Accurate thermal risk assessments require incorporating clothing ventilation characteristics.
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