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UTCI - nowe narzędzie badania warunków bioklimatycznych w różnych skalach czasowych i przestrzennych

Błażejczyk K., Broede P., Fiala D., Havenith G., Holmér I., Jendritzky G., Kampmann B.

Przegląd Geofizyczny

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2010

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Z. 1-2

5-19

PL

Spośród licznych wskaźników oceniających oddziaływanie środowiska atmosferycznego na człowieka tylko nieliczne mają bezpośrednie odniesienie do reakcji fizjologicznych zachodzących w organizmie. W ostatnich latach powstał kilka prostych i wielowęzłowych modeli bilansu cieplnego człowieka, które opisują złożone mechanizmy gospodarki cieplnej organizmu. Na bazie wielowęzłowego modelu Fiali powstał nowy wskaźnik oceniający obciążenia cieplne człowieka (UTCI). W artykule przedstawiono założenia i podstawy interpretacji wskaźnika oraz przykłady jego zastosowania w różnych skalach czasowych i przestrzennych.

EN

Starting from 1999, in the frame of International Society of Biometeorology special study group is working to develop new Universal Thermal Climate Index (UTCI). Since 2005 these efforts have been reinforced by the COST Action 730 of the European Science Foundation (ESF) in order to achieve significant progress in deriving such an index. The new UTCI index represents air temperature of the reference condition with the same physiological response as the actual condition. The index base on Fiala model that is one of the most advanced multi-node thermophysiological models. It includes the capability to predict both, whole body and local thermal effects. The model consists of two interacting thermoregulatory systems: the controlling active system and the controlled passive system. The passive system simulates the dynamic heat transfer phenomena that occur inside the body and at its surface. The active system is a model predicting the thermoregulatory reactions of the central nervous system. The assessment scale of UTCI base on the objective physiological reactions to environmental heat stress in wide range of weather and climates. As an example the index was applied to assess biothermal conditions it two patio-temporal scales: local and regional. The results show good representation of specific local and regional features of bioclimate. Thus, the index can be applicable in various research dealing with: bioclimatological assessments, bioclimatic mapping in all scales (from micro to macro), urban design, engineering of outdoor spaces, consultancy for where to live, outdoor recreation and climatotherapy, epidemiology and climate impact research.

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

Brode P., Kuklane K., Candas V., Den Hartog E. A., Griefahn B., Holmer I., Meinander H., Nocker W., Richards M., Havenith G.

International Journal of Occupational Safety and Ergonomics

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2010

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Vol. 16, No. 2

231--244

EN

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.

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Analytical Study of the Heat Loss Attenuation by Clothing on Thermal Manikins Under Radiative Heat Loads

Den Hartog E. A., Havenith G.

International Journal of Occupational Safety and Ergonomics

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2010

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Vol. 16, No. 2

245--261

EN

For wearers of protective clothing in radiation environments there are no quantitative guidelines available for the effect of a radiative heat load on heat exchange. Under the European Union funded project ThermProtect an analytical effort was defined to address the issue of radiative heat load while wearing protective clothing. As within the ThermProtect project much information has become available from thermal manikin experiments in thermal radiation environments, these sets of experimental data are used to verify the analytical approach. The analytical approach provided a good prediction of the heat loss in the manikin experiments, 95% of the variance was explained by the model. The model has not yet been validated at high radiative heat loads and neglects some physical properties of the radiation emissivity. Still, the analytical approach provides a pragmatic approach and may be useful for practical implementation in protective clothing standards for moderate thermal radiation environments.

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Dry and Wet Heat Transfer Through Clothing Dependent on the Clothing Properties Under Cold Conditions

Richards M. G. M., Rossi R., Meinander H., Broede P., Candas V., Hartog den E., Holmer I., Nocker W., Havenith G.

International Journal of Occupational Safety and Ergonomics

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2008

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Vol. 14, No. 1

69--76

EN

The purpose of this study was to investigate the effect of moisture on the heat transfer through clothing in relation to the water vapour resistance, type of underwear, location of the moisture and climate. This forms part of the work performed for work package 2 of the European Union THERMPROTECT project. Thermal manikin results of dry and wet heat loss are presented from different laboratories for a range of 2-layer clothing with similar dry insulations but different water vapour permeabilities and absorptive properties. The results obtained from the different manikins are generally consistent with one another. For each climate, total wet heat loss is predominately dependent on the permeability of the outer layer. At 10 °C, the apparent evaporative heat loss is markedly higher than expected from evaporation alone (measured at 34 °C), which is attributed to condensation within the clothing and to increased conductivity of the wet clothing layers.

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Calculation of Clothing Insulation by Serial and Parallel Methods: Effects on Clothing Choice by IREQ and Thermal Responses in the Cold

Kuklane K., Gao C., Holmer I., Giedraityte L., Brode P., Candas V., Hartog den E., Meinander H., Richards M., Havenith G.

International Journal of Occupational Safety and Ergonomics

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2007

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Vol. 13, No. 2

103--116

EN

Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values. Tests were carried out on 8 subjects. The results showed the possibility of incorporating the effect of increases in metabolic rate values due to thick cold protective clothing into the IREQ model. Using the higher thermal insulation value from the serial method in the IREQ prediction, would lead to unacceptable cooling of the users. Thus, only the parallel insulation calculation method in EN 342:2004 should be used. The wind and motion correction equation (No. 2) gave realistic values for total resultant insulation; dynamic testing according to EN 342:2004 may be omitted.