Abstract
Thermal insulation may be influenced by the size of clothing and thus the volume of air gaps. The aim of this study was to determine the relationship between the size of outer wear clothing, and thus the indirect fit (the volume and size of air gaps), and thermal insulation in static and dynamic conditions. A set of underwear and two types of outerwear for workers of the energy sector and the chemical industry were selected for the study. Results showed that the value of thermal insulation (regardless of the type of outerwear) first increased with increasing clothing size.