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EN
During the last century about 100 indices were developed to assess influences of the atmosphere on human being. However, most of them have not close relationships with physiological reactions in man. In 1999 International Society of Biometeorology established special study group do develop new Universal Thermal Climate Index (UTCI). Since 2005 these efforts have been reinforced by the COST Action 730 (Cooperation in Science and Technical Development). In February 2009 the Action was terminated and UTCI was developed. 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 and include the capability to predict both whole body thermal effects (hypothermia and hyperthermia; heat and cold discomfort), and local effects (facial, hands and feet cooling and frostbite). The model consists of two interacting systems: the controlling active system; and the controlled passive system. The assessment scale of UTCI bases on the intensity of objective physiological reactions to environmental heat stress in wide range of weather and climates. The index can be applicable in various research, for example in weather forecasts, 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. The paper presents thermophysiological principles of UTCI as well as some examples of its application to assess bioclimatic differentiation of Europe.
EN
The main goal of this paper was to assess the intensity of heat stress in Lower Silesia, Poland, during selected weather events characterized by high air temperatures. The complex impact of weather on the thermal load of the human organism is presented using the Universal Thermal Climate Index (UTCI). The analysis was carried out for the 2015 and 2018 summer seasons and compared with the multiannual period of 1971–2018. It was based on meteorological data from the IMGW-PIB stations of Wrocław, Jelenia Góra and Śnieżka. In order to examine how heat conditions affect UTCI in different geographical regions, stations located at different altitudes and representing the lowlands, the lower mountain zone and the summit zone of the Sudetes Mountains were considered. The research showed that during the most extreme thermal events, UTCI values in the lowlands and the lower mountain zones can be among the highest heat stress classes. In the summit zone, the maximum UTCI values are usually classed as ‘no thermal stress’.
EN
The continuous monitoring of the relationship between land surface temperature (LST) and land cover change is imperative for an inquiry into the potential impact of LST on human well-being, including urban outdoor thermal comfort in Lagos State, Nigeria. Using Landsat imagery, this study assessed land cover and LST changes from 1984 to 2019. Land cover was extracted, LST was determined from Landsat imageries and the land cover changes were linked to LST using the contribution index (CI). Afterwards, the universal thermal climate index (UTCI) was calculated to determine the heat stress levels. Findings confirm the presence of urban sprawl and new growth areas in previously rural Local Government Areas (LGAs) eastward, northward and westward of Lagos metropolis and in regions which lie on the fringe of the state’s border with Ogun State. Also, a very strong link between high LST intensities and increasing concentration of urban areas in rapidly growing LGAs has been observed. This link further confirms the increased warming of the state, with an increase in mean LST of 2.16°C during 1984–2019. The UTCI which was used to gauge the influence of LST on outdoor thermal comfort ranged from moderate to strong heat stress levels. This study helps to strengthen the case for definite policies and actions which should be aimed at achieving moderate urban development through increased urban tree canopy/green infrastructure provision and carbon sequestration activities in urban design/landscape design, in Lagos State.
EN
Objectives The objective of this study has been to evaluate the occupational heat exposure of 12 workers at 5 plants in a subtropical country. Material and Methods The heat stresses and strain on workers in 5 plants were assessed by the International Organization for Standardization (ISO) 7243 index (wet bulb globe temperature – WBGT) and the ISO 7933 index (maximum allowable exposure time – $ \text{D}_\text{lim} $). Results Results indicated that 42% of the subjects (5 workers) surpassed the WBGT limits. According to the $ \text{D}_\text{lim} $, 42% of the subjects could not continue working in the hot environments. The relationships between the various heat stress indices and the WBGT index were also correlated. However, further studies from different heat environments and more subjects should be performed. Conclusions The sensitive dependence of skin temperature on meteorological and physiological indices for each subject was clearly observed. Obviously, the heart rate response to metabolic rate was much greater than that caused by environmental heat alone. The exponential relationship between workers’ duration-limited exposure time, predicted by various estimated criteria, and WBGT were also found. Int J Occup Med Environ Health 2017;30(3):379–395
PL
Bodźcowość warunków biometeorologicznych we Wrocławiu przeanalizowana została na podstawie wartości wskaźnika oceny obciążeń cieplnych człowieka UTCI (Universal Thermal Climate Index) w latach 2008–2014. Wyliczono je z danych o kroku godzinowym otrzymanych z Obserwatorium Agro- i Hydrometeorologii Uniwersytetu Przyrodniczego we Wrocławiu, z uwzględnieniem składowych całkowitego bilansu promieniowania słonecznego. Analizie poddane zostały roczne i wieloletnie przebiegi wartości wskaźnika UTCI oraz częstość występowania klas wartości wskaźnika odpowiadających określonej bodźcowości (stres ciepła i zimna). Dla wybranych okresów fal ciepła i chłodu porównano przebiegi głównych meteorologicznych determinant wskaźnika UTCI. Potwierdzono słabą bodźcowość warunków biometeorologicznych Wrocławia. Wykazano, że warunki biometeorologiczne wrocławskich przedmieść charakteryzują się znaczną frekwencją braku obciążeń cieplnych. Zaznaczono, że w ostatnich latach wzrasta liczba sytuacji ze stresem zimna, co w obszarach o stosunkowo niskiej szorstkości podłoża spowodowane jest dynamiką ruchu powietrza w częściej występujących sytuacjach cyklonalnych.
EN
Stimulating qualities of biometeorological conditions of Wrocław were analyzed on the basis of the values of the Universal Thermal Climate Index (UTCI) of the years 2008–2014. UTCI values were calculated from 1-hour data with the use of components of solar radiation balance, measured in the Agro- and Hydrometeorological Observatory of Wrocław University of Environmental and Life Science. Annual and long-standing courses of UTCI and the occurrence frequency of UTCI levels corresponding to a specific stimulating condition (heat and cold stress) were analyzed. For the selected coldwave and heat-wave, the courses of the main meteorological determinants of UTCI were compared. It was demonstrated that the biometeorological conditions of Wrocław suburbia are characterized by a considerable frequency of heat load deficit. It was remarked that the number of incidents of cold stress has increased in recent years. In in the areas of relatively smal l surface roughness, the reason can be attributed to the dynamics of the wind in more frequently occurring cyclonic circulation.
EN
Background There are differences between dry and wet sauna baths because of the heat load and human body’s reactions. High humidity in a wet sauna makes evaporation of sweat from the skin surface more difficult. In addition, the dynamics of sweating is different in men and women. The aim of the study was to assess changes in physiological indicators and to compare the impact of dry and wet saunas on the thermal comfort feeling, which was assessed using the Bedford thermal scale, and the physiological strain index (PSI) and the cumulative heat stress index (CHSI) in young healthy women. Material and Methods Ten women aged 22−24 years took part in the study. A session in each sauna lasted 60 min and consisted of 3 thermal 15-min exposures, in 5-min intervals for rest and cooling with water. The temperature in the dry sauna was 91±1.2°C and in the wet sauna 59±1.3°C, while the humidity was 18±0.7% and 60.5±0.8%, respectively. Body weight, systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), rectal temperature ($ \text{T}_\text{re} $) and the thermal sensation (Bedford scale) were also measured. The PSI and CHSI values were both calculated. Results The average weight loss after a dry sauna bath was significantly higher than after a wet sauna bath. Significantly higher increases in $ \text{T}_\text{re} $, as well as in HR were observed after treatment in the wet sauna, compared to the dry sauna. Both treatments resulted in an increase in SBP and a decrease in DBP. The arduousness of thermal discomfort and the levels of PSI and CHSI were skurgreater in the wet sauna bathing than in the dry sauna. Conclusions Heat exposure in the wet sauna creates a greater burden for young women’s bodies than the same dry sauna treatment, and the changes observed in the examined traits were higher than in men subjected to similar thermal loads. Med Pr. 2019;70(6):701–10
PL
Wstęp Kąpiele w saunie suchej i w łaźni parowej ze względu na różny stopień obciążenia cieplnego wywołują też różne reakcje organizmu. Duża wilgotność powietrza w saunie mokrej utrudnia parowanie potu ze skóry. Ponadto dynamika pocenia się jest różna u kobiet i mężczyzn. Celem pracy była analiza zmian wskaźników fizjologicznych oraz porównanie wpływu sauny suchej i mokrej na odczucie komfortu cieplnego ocenianego w skali termicznej Bedforda, a także zbadanie wielkości obciążenia fizjologicznego (physiological strain index – PSI) i skumulowanego wskaźnika obciążeń cieplnych (cumulative heat stress index − CHSI) u młodych zdrowych kobiet. Materiał i metody W badaniach wzięło udział 10 kobiet w wieku 22−24 lat. Pomiary w obu typach sauny prowadzono w fazie folikularnej cyklu miesięcznego. Każda sesja trwała 60 min i składała się z trzech 15-minutowych ekspozycji cieplnych z 5-minutowymi przerwami na odpoczynek i schłodzenie wodą. Temperatura w saunie suchej wynosiła 91±1,2°C, w mokrej – 59±1,3°C; wilgotność powietrza, odpowiednio: 18±0,7% i 60,5±0,8%. Dokonano pomiarów masy ciała, ciśnienia skurczowego (systolic blood pressure − SBP) i rozkurczowego (diastolic blood pressure − DBP), częstości skurczów serca (heart rate − HR), temperatury rektalnej ($ \text{T}_\text{re} $) i odczuć termicznych według skali Bedforda. Wyliczono współczynniki obciążenia fizjologicznego: PSI oraz CHSI. Wyniki Po saunie suchej średnie ubytki masy ciała badanych kobiet były istotnie wyższe niż po kąpieli w saunie mokrej. Po zabiegu w saunie mokrej zaobserwowano istotnie większe przyrosty $ \text{T}_\text{re} $ oraz HR. Oba zabiegi powodowały wzrost SBP. Podczas obu kąpieli ciśnienie rozkurczowe ulegało obniżeniu. Subiektywne odczucie uciążliwości zabiegu oraz PSI i CHSI było większe podczas kąpieli w saunie mokrej. Wnioski Ekspozycja cieplna w saunie mokrej stanowi większe obciążenie dla organizmu młodych kobiet niż taki sam zabieg w saunie suchej, a zmiany badanych cech są większe od tych, które zaobserwowano u mężczyzn poddanych podobnym obciążeniom termicznym. Med. Pr. 2019;70(6):701–710
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