Gray water recycling and economical use of rainwater can be a valuable alternative source of water, especially for non-potable uses. These sources are seen as the basis of change in waters management, which gives a possibility of protection of still shrinking water resources. Taking into account continuing urbanization and population growth in the world, not only the management of water resources requires a change in attitudes, but also the management and conservation of conventional fuels that energy is generated of, and that are required for the development and functioning of urban areas. Bearing this in mind, some studies have been performed in order to establish the cost-effectiveness of application systems capable of reducing the demand for tap water and electricity used to heat it. A financial analysis with an application of the Life Cycle Cost methodology has been conducted for a multi-family residential building for seven different variants of installation of water and sewage, which assumed the use of the following solutions: gray water harvesting system, rainwater harvesting system and drain water heat recovery units. This analysis showed that the use of these systems in the tested building is financially viable, despite the fact that their implementation is associated with incurring higher investment cost than in the base case (Variant 0). The study was expanded by a sensitivity analysis on the basis of which it was possible to conclude that the project involving the use of alternative sources of pending water and energy in this building is only slightly susceptible to changes in calculation parameters.

Analysis of profitability of rainwater harvesting, gray water recycling and drain water heat recovery systems

The aim of this study was to evaluate the precision, accuracy, practicality, and potential uses of a PM2.5 miniaturized monitor (MM) in exposure assessment. These monitors (AirBeam, HabitatMap) were compared with the widely used direct-reading particulate matter monitors and a gravimetric reference method for PM2.5. Instruments were tested during 20 monitoring sessions that were subdivided in two different seasons to evaluate the performance of sensors across various environmental and meteorological conditions. Measurements were performed at an urban background site in Como, Italy. To evaluate the performance of the instruments, different analyses were conducted on 8-h averaged PM2.5 concentrations for comparison between direct-reading monitors and the gravimetric method, and minute-averaged data for comparison between the direct-reading instruments. A linear regression analysis was performed to evaluate whether the two measurement methods, when compared, could be considered comparable and/or mutually predictive. Further, Bland-Altman plots were used to determine whether the methods were characterized by specific biases. Finally, the correlations between the error associated with the direct-reading instruments and the meteorological parameters acquired at the sampling point were investigated. Principal results show a moderate degree of agreement between MMs and the reference method and a bias that increased with an increase in PM2.5 concentrations.

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Precision and Accuracy of a Direct-Reading Miniaturized Monitor in PM2.5 Exposure Assessment.

Indoor Environmental Quality is an important issue in educational buildings since it is directly related to students’ well-being and learning activities. Indoor Environmental Quality parameters hav...

Indoor environment quality assessment in classrooms: An integrated approach:

This paper aims to carry out measurements of indoor air temperature, relative humidity and carbon dioxide (CO2) concentrations as well as to determine CO2 production by students and teacher during ...

Investigation of CO2 production depending on physical activity of students.

Thermal comfort in primary school classrooms: A case study under subarctic climate area of Sweden

Investigation of Indoor Environment Quality in Classroom - Case Study

We performed comparative analysis of regulatory documents, which relate to ventilation of school premises and operate in European countries at present. We showed the essential difference of the recommended air exchange values. We assessed sanitary and hygienic conditions formed in classrooms at different efficiency of a ventilation system both by analytical calculations and by subjective monitoring of microclimate of experimental measurements conducted in school classrooms, when every pupil-participant performed an assessment of the internal environment in the form of a questionnaire. We measured carbonic acid gas contents emitted in a room and determined the required ventilation intensity in the evaluated school premises. We compared the multiplication factor of air exchange of the ventilation system determined in this way with the values obtained by analytical calculations carried out in accordance with current legislation and standards, which are active in Europe. We made calculations based on known analytical dependencies. We determined performance of the ventilation system of the classroom based on СО2 concentrations in internal and inflow air at various values of the multiplication factor of air exchange. It made possible to state that we can achieve the optimal microclimate parameters at air exchange of 30 m3/h per person.We presented the results of field studies and analytical calculations in the form of tables and visual graphic dependencies. The proposed research method makes it possible to increase accuracy and reliability of air quality control in classrooms by direct measurement of СО2 concentration in a serviced area of a room. The study results provide an opportunity to improve ventilation systems of school buildings. This creates prerequisites for obtaining a social effect due to an increase in labor and learning efficiency

/pdf/ensuring-comfort-microclimate-in-the-classrooms-under-5ejzv99vqa.pdf

Ensuring comfort microclimate in the classrooms under condition of the required air exchange

Investigation of IEQ and subjective evaluation of IEQ by pupils is the main objective of this research work. For the monitoring two classrooms in primary school and two classrooms in art school were chosen. Very high CO2 levels were determined in both investigated schools. In three of four classrooms the statistically significant differences (p < 0.01) were reported between TVOC levels in autumn and spring. The recommended value for TVOC levels was exceeded in the range from 52 % to 53 % in autumn and from 52 % to 70 % in spring. Significant (p < 0.05) seasonal changes were found also for PM concentrations in each classroom. Significance difference in perception of IEQ factors between genders were observed for IAQ. This study showed a good consistency between data obtained from the measurement and data from the questionnaire study and thus, pointed to the good ability of pupils to evaluate the IEQ in their classrooms.

The real and subjective indoor environmental quality in schools.

When reconstructing existing school buildings and building new buildings, great emphasis is placed on increasing their thermal resistance and reducing air tightness. The consequence of these modifications is the reduction of heat flow through the building structure, as well as minimization of uncontrolled ventilation by infiltration through building leaks. According to various studies conducted in the world, it can be said that the exchange of used air for fresh air has a huge impact on the mood of students in the classroom. As part of a research stay at the Lviv Polytechnic, measurements were made in the classroom to determine the air quality during the teaching. The classroom was selected in which measuring instruments were installed for measuring carbon dioxide (CO2) concentration and air temperature. During the measurements didactic classes took place in the classroom. In addition to the measurement of indoor air parameters, a subjective assessment of air quality was carried out using questionnaires. The students filled out the indoor air quality questionnaire at the beginning of their stay in the auditorium at the end of their stay. An assessment of air quality was carried out based on the measured air parameters and questionnaire ratings in the selected classroom.

Investigation of Indoor Air Quality in the Selected Ukraine Classroom – Case Study

Considering the fact that in operating costs of the new building the important place take expenses on heating, mainly, on air heating in systems of ventilation, the measures directed on optimization of the intensity of ventilation at maintaining comfort of consumers, are of high importance and have national character. To reduce electricity consumption it is possible to use air-conditioning equipment providing heat recovery from exhaust air. When choosing the ventilating equipment it is necessary to consider the correct boundary conditions that the ventilating equipment wasn't the overestimated or underestimated power with the aim of optimizing investment and operating costs of ventilation equipment in compliance with sanitary requirements with regard to air quality in the internal environment of buildings. This paper is aimed to develop a methodology for determining the intensity of ventilation of indoor premises based on the experimental measurements of the concentration of carbon dioxide (CO2). Using experimental measurements and the knowledge gained in the study of this issue, in the work the method for intensity ventilation determining of the indoor premises was developed on the basis of the measured values of carbon dioxide which was verified also by another experimental measurements. The resulting values of ventilation intensity rate obtained by calculation from the measured values of carbon dioxide were compared with the results of calculations executed according to the laws and standards, current in Slovakia. Based on comparison of the results one of the methods for calculation of the ventilation intensity was developed that is valid in Slovakia, the results of which were close to the results obtained by the method of determining the intensity of ventilation rate in the room on the basis of the measured values of carbon dioxide. The above mentioned method is determined by the method of calculating intensity of ventilation rate in the rooms intended for offices.

Peter Kapalo

Papers

Investigation of Indoor Environment Quality in Classroom - Case Study

Ensuring comfort microclimate in the classrooms under condition of the required air exchange

The real and subjective indoor environmental quality in schools.

Investigation of Indoor Air Quality in the Selected Ukraine Classroom – Case Study

Using Experimental Measurements the Concentrations of Carbon Dioxide for Determining the Intensity of Ventilation in the Rooms