Efficacy of warming systems in mountain rescue : an experimental manikin study

Mountain accident casualties are often exposed to cold and windy weather. This may induce post-traumatic hypothermia which increases mortality. The aim of this study was to assess the ability of warming systems to compensate for the victim’s estimated heat loss in a simulated mountain rescue operation. We used thermal manikins and developed a thermodynamic model of a virtual patient. Manikins were placed on a mountain rescue stretcher and exposed to wind chill indices of 0 °C and - 20 °C in a climatic chamber. We calculated the heat balance for two simulated clinical scenarios with both a shivering and non-shivering victim and measured the heat gain from gel, electrical, and chemical warming systems for 3.5 h. The heat balance in the simulated shivering patient was positive. In the non-shivering patient, we found a negative heat balance for both simulated weather conditions (- 429.53 kJ at 0 °C and -1469.78 kJ at - 20 °C). Each warming system delivered about 300 kJ. The efficacy of the gel and electrical systems was higher within the first hour than later (p < 0.001). We conclude that none of the tested warming systems is able to compensate for heat loss in a simulated model of a non-shivering patient whose physiological heat production is impaired during a prolonged mountain evacuation. Additional thermal insulation seems to be required in these settings

Ocena jakości powietrza wewnętrznego w wybranych przedszkolach

The article presents the results of indoor air quality (IAQ) assessment in four local preschools. The natural ventilation system was used in the buildings. Outdoor air was supplied to the premises through a leak in the external walls and air intakes were of&nbsp;maximum efficiency of 30 m3/h. Parameters describing IAQ were measured, such as: temperature, relative humidity and carbon dioxide concentration. Two series of studies were performed in each preschool. On the basis of the survey, it can be clearly stated that the indoor air quality in preschools is considered to be very low very low. All the analyzed parameters describing the quality do not meet the current legal requirements. Reported values of CO2 concentration exceeded three times the value set of the recommended maximum.W artykule przedstawiono wyniki badań jakości powietrza wewnętrznego przeprowadzonych w 4 przedszkolach samorządowych. W rozpatrywanych obiektach zastosowany został system wentylacji grawitacyjnej. Uzyskane wyniki badań wskazują jednoznacznie na bardzo niską jakość powietrza w tego typy budynkach

Jakość powietrza w wielorodzinnych budynkach mieszkalnych

The applicable legislation connected with the natural ventilation are ambiguous and sometimes contradictory. This leads to serious problems with natural ventilation. In most cases malfunction of the natural ventilation is due to the insufficient stream of air from the outside. The research showed that the microclimate is influenced not only by the incoming air stream, but also by the layout of the air supply.Obowiązujące aktualnie przepisy prawne regulujące zagadnienia wentylacji naturalnej&nbsp; [1], [2], [3] w wielu obszarach są niejednoznaczne, a niekiedy wręcz sprzeczne. Sytuacja taka prowadzi do stosowania rozwiązań powodujących poważne zaburzenia w działaniu wentylacji grawitacyjnej. W dużej części budynków zaburzenia te są wynikiem dostarczania do pomieszczeń zbyt małej ilości powietrza zewnętrznego. Jak wykazały badania, ze względu na kształtowanie warunków mikroklimatu wnętrz, podstawowe znaczenie ma nie tylko wielkość dostarczanego strumienia powietrza zewnętrznego, ale również rozmieszczenie elementów doprowadzających to powietrze

Preliminary results of thermal comfort analysis in selected buildings

The paper analyses thermal comfort in an intelligent building. Intelligent buildings are now widely seen both in Poland and abroad as a result of developments in engineering sciences. However, data on the thermal comfort provided in the buildings are limited. The research described in this paper was carried out in ENERGIS intelligent building of the Kielce University of Technology. The parameters measured included air temperature, relative air humidity, air flow rate and carbon dioxide concentration. Average radiation temperature was determined. The key element was the study of thermal sensation in occupants present at the time of the measurements. The studies were performed in classrooms during the class. The students completed a questionnaire at the beginning and end of the class. The persons present in the classrooms evaluated their thermal sensations using a seven-level thermal comfort scale. The questionnaire included such questions as the type of clothing and the degree of physical activity of the people sitting in the classroom. On the basis of the measurements of classroom microclimate parameters, PMV (Predicted Mean Vote) and PPD (Predicted Percentage Dissatisfied) indices were determined. The responses from the questionnaires provided actual average assessment of thermal sensation and actual percentage of dissatisfied people

Preliminary results of thermal comfort analysis in selected buildings

The paper analyses thermal comfort in an intelligent building. Intelligent buildings are now widely seen both in Poland and abroad as a result of developments in engineering sciences. However, data on the thermal comfort provided in the buildings are limited. The research described in this paper was carried out in ENERGIS intelligent building of the Kielce University of Technology. The parameters measured included air temperature, relative air humidity, air flow rate and carbon dioxide concentration. Average radiation temperature was determined. The key element was the study of thermal sensation in occupants present at the time of the measurements. The studies were performed in classrooms during the class. The students completed a questionnaire at the beginning and end of the class. The persons present in the classrooms evaluated their thermal sensations using a seven-level thermal comfort scale. The questionnaire included such questions as the type of clothing and the degree of physical activity of the people sitting in the classroom. On the basis of the measurements of classroom microclimate parameters, PMV (Predicted Mean Vote) and PPD (Predicted Percentage Dissatisfied) indices were determined. The responses from the questionnaires provided actual average assessment of thermal sensation and actual percentage of dissatisfied people

Influence of Masks Protecting against SARS-CoV-2 on Thermal Comfort

Due to the spread of the SARS-CoV-2 virus, most countries have tightened their public health policies. One way to limit the spread of the virus is to make mouth and nose cover compulsory in public spaces. The article presents the impact of wearing masks on the perception of thermal comfort. The following masks were analysed: FFP2, cotton, medical, PM2.5, half-face protective shield plastic and full-face protective shield plastic. The research was carried out for two scenarios of an ambient temperature: −20 and 30 °C. A thermal manikin was used for the tests. In the case of when a temperature equals 20 °C, the dry masks increase comfort, both general and local, while wet masks reduce comfort. On the other hand, at 30 °C, only wet masks do not increase discomfort. In addition, moist masks require less heat flux to achieve a certain skin temperature. However, it should be remembered that it is not advisable to wet the masks from the health point of view

A Method of Multi-Criteria Assessment of the Building Energy Consumption

The aim of this study is to develop a universal method for the unequivocal selection of the optimal combination of components determining the energy efficiency of buildings by means of an introduced global building energy consumption indicator. The basis of this method is a multi-criteria optimization of the components influencing the energy efficiency of buildings. The method requires the development of a detailed description of the set of components influencing the energy efficiency of buildings and the definition of the analysis criteria. The following analysis criteria were adopted: relative annual demand for final energy, cost, durability, and investment outlays payback time. The normalized values of these criteria are calculated in relation to the structure of a reference building. The proposed method makes it possible to explicitly indicate the most advantageous solution from the point of view of the weighted share of the individual criteria. The verification of the method was presented on the basis of the thermo modernization case study analysis for the adopted reference building. As a result, the most advantageous variant of modernization was determined, defined by the lowest value of the global building energy consumption indicator. A high effectiveness of the proposed method has been shown in relation to both the selection of the modernization option and the assessment of the individual component share in each modernization solution

Assessment of Thermal Comfort in Rooms Equipped with a Decentralised Fa&ccedil;ade Ventilation Unit

Thermal comfort affects not only the well-being of the occupants of a building but also the effectiveness of their learning and work efficiency. It can be disturbed if the ventilation airflow is increased when improving indoor air quality. When natural ventilation is used in the fall and winter period, the supply air temperature is low, resulting in a lack of thermal comfort. In existing buildings, there is often no place for mechanical ventilation; hence, decentralised fa&ccedil;ade ventilation units are increasingly used. The article presents an analysis of thermal comfort in rooms with this type of unit equipped with heat recovery exchangers of different efficiencies. Studies have shown that the alternating supply/exhaust airflow and the related unevenness of air streams flowing through the heat accumulator cause an inflow of low-temperature air, resulting in thermal discomfort. The highest value of the PMV index was &minus;1.6, and the lowest was &minus;4.1, which means that 54.8 to 100% of the occupants are dissatisfied with their thermal comfort. This means there is a need to change the construction of inlet/exhaust vents so that the stream of supply air is not directly parallel to the floor. In addition, the use of an air heater should be considered

Assessment of Thermal Comfort in Rooms Equipped with a Decentralised Façade Ventilation Unit

Thermal comfort affects not only the well-being of the occupants of a building but also the effectiveness of their learning and work efficiency. It can be disturbed if the ventilation airflow is increased when improving indoor air quality. When natural ventilation is used in the fall and winter period, the supply air temperature is low, resulting in a lack of thermal comfort. In existing buildings, there is often no place for mechanical ventilation; hence, decentralised façade ventilation units are increasingly used. The article presents an analysis of thermal comfort in rooms with this type of unit equipped with heat recovery exchangers of different efficiencies. Studies have shown that the alternating supply/exhaust airflow and the related unevenness of air streams flowing through the heat accumulator cause an inflow of low-temperature air, resulting in thermal discomfort. The highest value of the PMV index was −1.6, and the lowest was −4.1, which means that 54.8 to 100% of the occupants are dissatisfied with their thermal comfort. This means there is a need to change the construction of inlet/exhaust vents so that the stream of supply air is not directly parallel to the floor. In addition, the use of an air heater should be considered

Próba poprawy jakości powietrza wewnętrznego w przedszkolu

The article demonstrates the results of research on the indoor air quality (IAQ) in one of chosen preschools. In such facilities, the standard solution is a system of natural ventilation. Only a small percentage of such buildings is equipped with a mechanical ventilation system with adjustable parameters of the microclimate. The article presents the results of indoor air quality in the local preschool located in Kielce. In the present facility natural ventilation system was used. Preliminary studies confirmed the poor quality of&nbsp;indoor air in a subjected building. During the study, two improvements aimed at improving air quality were proposed. The first improvement was to increase the supply air stream. The&nbsp;second one concerned the installation of equipment for the treatment of indoor air. The&nbsp;results indicate that under certain guidelines it is possible to improve indoor air quality. As an indicator of indoor air quality, concentration of carbon dioxide was adopted. In&nbsp;addition, microbiological tests were performed indoors.W artykule przedstawiono wyniki badań nad jakością powietrza wewnętrznego (IAQ) w jednym z wybranych przedszkoli. W obiekcie zastosowany został system wentylacji grawitacyjnej. Wstępne badania potwierdziły niską jakość powietrza wewnętrznego w podmiotowym budynku. W trakcie badań zaproponowano dwa usprawnienia mające na celu poprawę jakości powietrza: zwiększenie strumienia powietrza nawiewanego oraz, w drugiej kolejności, montaż urządzeń do uzdatniania powietrza wewnętrznego. Uzyskane wyniki badań wskazują, że wprowadzone usprawnienia wpływają na poprawę jakości powietrza wewnętrznego