Heat Gain From Thermal Radiation Through Protective Clothing With Different Insulation, Reflectivity and Vapour Permeability

Abstract

The heat transferred through protective clothing under long wave radiation compared to a reference condition without radiant stress was determined in thermal manikin experiments. The influence of clothing insulation and reflectivity, and the interaction with wind and wet underclothing were considered. Garments with different outer materials and colours and additionally an aluminised reflective suit were combined with different number and types of dry and pre-wetted underwear layers. Under radiant stress, whole body heat loss decreased, i.e., heat gain occurred compared to the reference. This heat gain increased with radiation intensity, and decreased with air velocity and clothing insulation. Except for the reflective outer layer that showed only minimal heat gain over the whole range of radiation intensities, the influence of the outer garments' material and colour was small with dry clothing. Wetting the underclothing for simulating sweat accumulation, however, caused differing effects with higher heat gain in less permeable garments.

Deriving the operational procedure for the Universal Thermal Climate Index (UTCI)

“…The psychrometric chart describing the mutual effects of temperature and humidity in warm climates was in good agreement with the charts obtained for physiological data from human experiments as described elsewhere (Kampmann 2000) and also in this issue . The extra heat load by thermal radiation and its interaction with wind speed was also recently observed with work clothes (Bröde et al 2010b). In the cold, UTCI indicated more pronounced effects of wind speed compared to the wind chill temperature (Bröde et al 2010a).…”

“…However, the outdoor thermal comfort may also be influenced by the activity level, i.e. metabolic rate (Vanos et al 2010;Kenny et al 2009b), special clothing, as, e.g., required when assessing the thermal load of the working population (Bröde et al 2010b;Havenith et al 2008;Kjellström et al 2009), and by rain and wet clothing Munir et al 2010). Further applications may also aim at providing guidance on the choice of clothing depending on the climatic conditions and activity level (Morabito et al 2008).…”

Characterizing Wildland Firefighters’ Thermal Environment During Live-Fire Suppression

“…However, to our knowledge no previous studies have investigated the exposure to heat flux that wildland firefighters have to withstand during real wildfire situations. This variable can significantly raise the environmental thermal load during fire suppression (Bröde et al, 2010; Willi et al, 2016) In addition, a direct exposure to thermal radiation and convection emitted by the flames elevates the risk of heat injuries (Rossi, 2003; Raimundo and Figueiredo, 2009). It has been reported in American wildland firefighters that 66% of injuries during wildfire suppression (between 2003 and 2007) were heat burns (Britton et al, 2013).…”

Toward Visual Avatars that Dress You Well and Impact Your Health

“…Therefore, a firefighter protective clothing requires a high level of heat-insulation for thermal protection. Conversely, this requirement hinders the process of dissipating sufficient metabolic heat to the environment, and may result in an increase in core temperature causing heat-related illnesses such as heat cramps, heat exhaustion, heat stroke, and even death [5][6][7][8]. In addition, firefighters' tasks such as fire suppression, search and technical rescues work demand a high physical burden and entails a large amount of energy consumption [9].…”