Indoor Environmental Assessment Research Articles

The Comfort Assessment of Indoor Environment Using Reinforcement Learning

The Comfort Assessment of Indoor Environment Using Reinforcement Learning

A BIM-enabled digital twin framework for real-time indoor environment monitoring and visualization by integrating autonomous robotics, LiDAR-based 3D mobile mapping, IoT sensing, and indoor positioning technologies

Existing indoor environment monitoring methods often fall short due to the lack of using standardized evaluation methods, missing spatial information, or the absence of user-friendly visualization interfaces. To address these limitations, this paper proposes a novel digital twin framework for real-time indoor environment monitoring and visualization by integrating Building Information Modeling (BIM), Internet of Things, autonomous robot-based mobile mapping and sensing, and indoor positioning technologies. The goal is to autonomously monitor indoor environmental conditions and provide real-time visualization using a standardized assessment index with estimated spatial information in BIM software. The proposed framework was demonstrated and validated in two indoor scenarios for air quality monitoring and visualization-related applications. Implementation results revealed that: the framework effectively captured spatial characteristics of air quality in small and medium-sized indoor spaces and intuitively visualized it using a BIM digital twin model; and, the ultra-wideband-based indoor positioning system achieved a nearly centimeter-level positioning precision. Practical interpretations of the results demonstrated that the proposed framework can not only detect and localize the potential sources of air pollutants but can also identify the possible causes of low indoor air quality. This study ultimately contributes to the body of knowledge by offering a novel and generic digital twin framework that seamlessly bridges various popular yet previously isolated technologies for better informing building facility management-related decisions. This paper is the first research work that integrates several emerging technologies (i.e., BIM, digital twins, IoT sensing, indoor localization/positioning/tracking, and robotics) for advancing real-time monitoring and visualization of indoor environmental conditions. While the proposed framework was applied for indoor air quality monitoring, it could be extended and used for various indoor environmental assessment and visualization-related applications.

Comparative Analysis of Subjective Indoor Environment Assessment in Actual and Simulated Conditions

This paper experimentally analyses an indoor environment assessment of a large group of respondents regarding their subjective perception of overall comfort, indoor air quality and humidity. The questionnaire survey was applied as a testing method together with measurements of the physical parameters conducted with a microclimate meter. Two types of environment were analysed: educational rooms and the climate chamber. The comparative analysis of the sensations experienced within them indicates that they generate quite similar responses; however, some discrepancies have been identified. The overall comfort of the climate chamber was typically assessed as being higher than that of the educational rooms at the same air temperature. The most favourable air temperature in the climate chamber was ca. 20.7 °C, while in the educational rooms it was ca. 22.3 °C. The most preferable conditions in the climate chamber occurred at a thermal sensation vote of −0.4 (“pleasantly slightly cool”), while in the educational rooms it occurred at +0.2 (“neutral/pleasantly slightly warm”). Quite strong correlations between overall comfort and indoor air quality as well as between humidity assessment and humidity preference votes were observed, which did not seem to depend on the type of environment. These findings are important because results from the simulated conditions are often used in the analyses of actual living/working environments.

Holistic analysis of indoor environmental quality in refurbished school using HAIEQ methodology - Czech case study

The subject of this paper is a detailed analysis and evaluation - audit of the quality of the indoor environment in the reference zone of a primary school building in the Czech Republic. The analysis and subsequent evaluation is performed by the certified CTU HAIEQ (Holistic Assesment of Indoor Environmental Quality) methodology, developed at the Department of Building and Construction Engineering of the Czech Technical University in Prague. The analysis is based on a detailed survey of the building, measured data of physical variables of the indoor environment and subjective assessment from the user's point of view. The evaluation of the quality of the environment is carried out in 8 categories - LS Location and location of the building in terms of external environment and social connections; STI Structural-technical design and interior of the evaluated zone; TCW Thermal comfort in cold season; TCS Thermal comfort in warm season; IAQ Air quality; LC Light environment; AC Acoustic environment and EC Electro-magnetic, -ionic -static fields. Each category has 5-8 criteria to be evaluated. The outcome of the indoor environment audit using the HAIEQ methodology is the identification of critical areas and the proposal of possible measures to improve the current situation. The implementation of the proposed measures must be carried out in accordance with applicable regulations and laws by authorized persons. The method used does not guarantee that all problem areas will be found using it and the preparer is not responsible for problems not found during the analysis of the building. The results of the measurement and evaluation methodology are not a substitute for an assessment by a sanitary service.

Indoor environment assessment of special wards of educational hospitals for the detection of fungal contamination sources: A multi-center study (2019-2021).

The hospital environment was reported as a real habitat for different microorganisms, especially mold fungi. On the other hand, these opportunistic fungi were considered hospital-acquired mold infections in patients with weak immune status. Therefore, this multi-center study aimed to evaluate 23 hospitals in 18 provinces of Iran for fungal contamination sources. In total, 43 opened Petri plates and 213 surface samples were collected throughout different wards of 23 hospitals. All collected samples were inoculated into Sabouraud Dextrose Agar containing Chloramphenicol (SC), and the plates were then incubated at 27-30ºC for 7-14 days. A total of 210 fungal colonies from equipment (162, 77.1%) and air (48, 22.9%) were identified. The most predominant isolated genus was Aspergillus (47.5%), followed by Rhizopus (14.2%), Mucor (11.7%), and Cladosporium (9.2%). Aspergillus (39.5%), Cladosporium (16.6%), as well as Penicillium and Sterile hyphae (10.4% each), were the most isolates from the air samples. Moreover, intensive care units (38.5%) and operating rooms (21.9%) had the highest number of isolated fungal colonies. Out of 256 collected samples from equipment and air, 163 (63.7%) were positive for fungal growth. The rate of fungal contamination in instrument and air samples was 128/213 (60.1%) and 35/43 (81.2%), respectively. Among the isolated species of Aspergillus, A. flavus complex (38/96, 39.6%), A. niger complex (31/96, 32.3%), and A. fumigatus complex (15/96, 15.6%) were the commonest species. According to our findings, in addition to air, equipment and instrument should be considered among the significant sources of fungal contamination in the indoor environment of hospitals.

Human Exposure Assessment to Air Pollutants in AC Filters from Agricultural, Industrial, and Residential Areas

High levels of potentially toxic metals and microbes in the atmosphere, especially indoor air, may severely threaten human health. Therefore, the concentration and associated health risks of heavy metals (Cd, Cr, Pb, Cu, Fe, Mn, and Zn), biological pollutants, and their risk to human health were assessed using air condition (AC) filter dust samples. Samples were collected from five locations representing agricultural, industrial, and residential settings of the Eastern Province, Kingdom of Saudi Arabia. The levels of trace metals varied considerably among sampling areas, with the highest levels of Cr and Cd recorded in the industrial area sites, followed by the agricultural and residential sites. The highest levels of Pb and Fe were found in the agricultural area sites, followed by the industrial and residential area sites. Among all the metals Cd, Cr, and Pb, showed a considerable health risk through a dermal pathway, and health risks for children from indoor dust exposure were higher compared to adults. Among the sites, the highest hazard quotient for these metals was found for Al-Qatif industrial area sites, and among the metals, it was the highest for Cd. The cancer risk from the metals contained in AC filter dust was negligible. Samples collected from agricultural and industrial area sites were substantially contaminated with bacteria and fungi, respectively. Bacterial contaminants were mostly Gram-negative, with considerable antibiotic resistance and hemolytic activity. Thus, indoor air quality assessed by AC filter dust depicted that the trace heavy metals and microorganisms could pose a considerable health risk for long-term exposure. Furthermore, this study demonstrated that AC filter dust could be a unique and reliable test sample for indoor environment assessment.

Comparative assessment of indoor and outdoor air environment of poultry farms in Edo State, Nigeria

Intensive poultry farming creates the ideal environment for pathogen concentration and transmission. The presence of thousands of birds in an enclosed, warm, and dusty atmosphere is ideal for the transmission of infectious diseases from birds to humans. This study was conducted to assess the indoor and outdoor air quality of different poultry types in Edo State, Nigeria. The physicochemical conditions of the air around the poultry environments differed with location and poultry types. The concentrations of carbon dioxide (CO2,), nitrous oxide (N2O), hydrogen sulphide (H2S) as well as particulate matter (PM10) were all within recommended limits established by the World Health Organization. However, significant elevations in Ammonia (NH3) and sulphur dioxide (SO2) levels were observed in substandard poultry farms across the locations. Total bacterial counts ranged from 1.38CFU/m5 – 90.35 x105CFU/m3 irrespective of location and poultry type. Within the poultry types, bacteria count inside the poultry environment (3.11 x105CFU/m3) significantly differed from concentrations outside the poultry environment (22.58 x105CFU/m3, p<0.05). The Lowest microbial counts were obtained in the standard poultry farms. Molecular identifications revealed the presence of Escherichia coli, Streptococcus pyogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, Bacillus subtilis as the bacterial isolates whereas Fusarium oxysporum, Aspergillus niger, Rhizopus stolonifer, Trichoderma polysporum, Aspergillus fumigatus were the fungal isolates. Staphylococcusaureus was the most predominant bacterial species (25%) while Aspergillus niger was the most predominant fungal species (30%).

Indoor environmental assessment: Comparing ventilation scenarios in pre- and post-retrofitted dwellings through test cells

In the next few years, outdoor temperature is expected to increase significantly as a result of climate change, a noticeable phenomenon, especially in the Mediterranean. In this future scenario, ventilation is a low-cost and useful strategy for tackling indoor overheating, mainly in energy-poor housing buildings. This research assesses the influence of different ventilation systems, air rates and schedules on the thermal comfort and indoor air quality of a residential retrofitted space when compared to an un-retrofitted environment, through test cell measurements. To do so, the methodology combines on-site monitoring with numerical models, simultaneously analysing both spaces under the same climate conditions. Results obtained show barely perceptible differences between the implementation of a mechanical ventilation system and a natural one, when it comes to thermal comfort in spaces with low thermal inertia, highlighting the clear advantage of energy and economic savings of the passive system. • The differences between IAQ in pre-/post-retrofitted ventilated spaces are minimal. • Inadequate ventilation periods negatively affect both IAQ and thermal comfort. • Short-term ventilation periods are useful for occasionally reducing high CO 2 . • Long-term ventilation periods are required to maintain IAQ with high occupancy. • Night ventilation is effective if applied under specific thermal conditions.

Condition assessment model of building indoor environment: a case study on educational buildings

PurposeThe purpose of this study is to develop a condition assessment (CA) model for a building's indoor 21 environments and to improve the building's asset management process.Design/methodology/approachThe methodology is based on dividing the building into spaces, which are the principal evaluated elements based on the building's indoor environmental quality (IEQ). An evaluation scheme was prepared for the identified factors and the analytical hierarchy process (AHP) technique was used to calculate the relative weight of each space inside the building as well as the contribution of each IEQ factors (IEQFs) in the overall environmental condition of each space inside the building. The multi-attribute utility theory (MAUT) was then applied to assess the environmental conditions of the building as a whole and its spaces. An educational building in Canada was evaluated using the developed model.FindingsEach space type was found to have its own IEQFs weights, which confirms the hypothesis that the importance and allocation of each IEQF are dependent on the function and tasks carried out in each space. A similar indoor environmental assessment score was calculated using the developed model and the building CA conducted by the facility management team; “89%” was calculated, using K-mean clustering, for the physical and environmental conditions.Originality/valueIEQ affects occupants' assessment of their quality of life (QOL). Despite the existence of IEQ evaluation models that correlate the building's IEQ and the occupants' perceived indoor assessments, some limitations have led to the necessity of developing a comprehensive model that integrates all factors and their sub-criteria in an assessment scheme that converts all the indoor environmental factors into objective metrics.

Comprehensive Assessment of Thermal Comfort and Indoor Environment of Traditional Historic Stilt House, a Case of Dong Minority Dwelling, China

The stilt house is one of the most representative of Chinese architecture among national minority traditional dwellings, most of which are located in mountainous regions whose climate is characterized by hot summers and cold winters. Moreover, it is widely distributed in Southeast Asian countries, such as Thailand, Laos, Cambodia, etc., as well as tropics like Hawaii, Guam. These kinds of dwellings have unique architectural aesthetics as well as high climate adaptability. However, because of their remote locations and rapid disappearance in urbanization, few studies have focused on their real indoor environment and thermal comfort. More studies were engaged in their architectural aesthetics and space patterns. In this study, based on the measurement and evaluation of residential natural lighting, ventilation, air quality, and thermal comfort in traditional stilt Dong village houses, the air temperature, humidity, CO2 and PM2.5 concentrations, wind speed, direction, and other variables are monitored and analyzed. Results show that the inhabitants have a higher thermal comfort adaptation than urban residents under natural ventilation. Meanwhile, the humidity of Dong stilt dwelling can reach a satisfactory level within 24 h except for the morning period. The satisfaction of the acoustic environment needs to be improved via reasonable structural maintenance.

Thermal comfort in physiotherapy centers: Evaluation of the neutral temperature and interaction with the other comfort domains

Not many studies regarding comfort in physiotherapy centers are present in literature. These facilities host both therapists and patients, who can have different age and health status and perform different activities. For this reason, the assessment of indoor environment can be difficult, and models available in technical standards and in the literature may poorly represent the occupants of physiotherapy centers. In this study, environmental well-being of therapists and patients was analysed in two facilities located in Italy and Denmark, in terms of thermal comfort and its interaction with other environmental quality domains (visual, air quality, acoustic). Separately for the heating and non-heating periods, measurements of the physical quantities and subjective questionnaire surveys were applied. Fanger's and adaptive models were used, while the influence of metabolic rate and subjective parameters on thermal comfort of occupants was investigated with statistical analyses. The neutral temperatures of the different occupants were assessed by means of different methods, and statistical analyses allowed to study the interaction of thermal comfort with the other domains. The study highlighted: 1. Limitations of current thermal comfort models when used in physiotherapy centers, being the metabolic rate difficult to estimate and subjective thermal sensation and satisfaction dependent on subjective parameters not included in the models (type of occupant, age, health status and gender); 2. Unsuitability of linear regression for estimating the neutral temperatures; 3. High tolerance and adaptability of therapists and patients to the temperatures in both seasons; 4. Association of thermal satisfaction with satisfaction with other environmental parameters.

Indoor Environmental Health Assessment in Eco-Building and Its Case Study

It is necessary to consider all aspects of environmental factors when assessing the health impact of an eco-building environment on its occupants. However, the multi-criteria and imprecise nature of the indoor-environment in the eco-buildings has caused difficulties in quantifying the indoor environmental pollution level. This paper describes the optimal classification and priority weight methods, which are particularly useful for assessing the indoor environmental quality (IEQ) of an eco-building to demonstrate its innovative applications. The analytic hierarchy process (AHP) was used to set up the strategic decision-making evaluation system for computing the indoor environment index (IEI) risk ranking of eco-buildings. Combined with this, a Microsoft Delphi-based IEQ intelligent forecasting software simulations package was developed, and the innovative application of indoor environmental comprehensive assessment was verified by a case study in Shanghai. The evaluation result was analyzed by the priority weight methods and the AHP decision-making system noted above. This health assessment method and system provides an innovative way for the indoor environment risk evaluation of eco-buildings and is helpful to standardize the local building market.

Developing an Indoor Environment Assessment Tool for Residential Buildings

The Indoor Environmental Quality (IEQ) describes an indoor space condition that the wellbeing and comfortability are provided for the users. Many researchers have highlighted the importance of adopting IEQ criteria, although they are not yet well defined in the Kurdistan region. However, environmental quality is not necessary for the contemporary buildings of the Kurdistan Region, and there is no measurement tool in the Region. This research aims to develop an IEQ assessment tool for the Kurdistan region using Mixed method methodology, both qualitative and quantitative. Therefore, a Delphi Technique was used as a method initially developed as systematic, interactive forecasting on a panel of experts. Thirty-five Delphi Candidates have reached an agreement on selecting the criteria for the IEQ, as Spss and a particular equation has used to find criteria weights. As a result, seven criteria with 22 indicators have been selected by expert ratings. A computer-based tool (KIEQA) has been created based on the scores selected by experts. Research results show that good IEQ is essential for interior design. It also offers a suitable indoor environment for users. This research has many significant advantages since it can raise awareness of issues of indoor environmental quality for architects, experts, and policymakers. Furthermore, to draw up an action plan for existing and new interior design projects in the Kurdistan Region. Future researches may concentrate on the correlation between IEQ criteria and to develop this tool regarding different building typologies.

Simulation analysis and thermal comfort assessment of indoor environment of the heritage building in gate tower

The thermal comfort inside heritage buildings in China is mostly achieved with the use of split air conditioning and radiator heating system. Due to inefficiencies in the design of those systems, the regulation of air temperature is generally inadequate. To meet the thermal comfort requirements of the partial significant room, which is the meeting hall area, and to preserve the external walls and facade, this paper simulates and analyses typical working conditions of air control schemes in the gate tower and suggests the use of a floor-type fan coil air conditioning system. The results show that the proposed air distribution system can maintain a temperature of 295 K in the summer, which meets the thermal comfort requirements of the meeting hall. This method takes into account the requirement for thermal comfort, as well as the requirements of heritage preservation. Our proposal contributes to the growing literature, which studies methods of improving the thermal comfort of the indoor environment of heritage buildings.

Classroom Indoor Environment Assessment through Architectural Analysis for the Design of Efficient Schools

Optimization of environmental performance is one of the standards to be achieved towards designing sustainable buildings. Many researchers are focusing on zero emission building; however, it is essential that the indoor environment favors the performance of the building purpose. Empirical research has demonstrated the influence of architectural space variables on student performance, but they have not focused on holistic studies that compare how space influences different academic performance, such as Mathematics and Arts. This manuscript explores, under self-reported data, the relationship between learning space and the mathematics and art performance in 583 primary school students in Galicia (Spain). For this, the Indoor Physical Environment Perception scale has been adapted and validated and conducted in 27 classrooms. The results of the Exploratory Factor Analysis have evidenced that the learning space is structured in three categories: Workspace comfort, natural environment and building comfort. Multiple linear regression analyses have supported previous research and bring new findings concerning that the indoor environment variables do not influence in the same way different activities of school architecture.

Indoor environmental assessment method in residential kitchen

Nowadays, energy consumption, environmental protection and safety are fundamental issues in design process. In order to reduce energy consumption, buildings become increasingly insulated and air tight. It has controversial effect on indoor environment, therefore, it has become essential to apply an effective ventilation system. This requires detailed design, especially if there is a strong, local source in the space. In residential buildings, gas stoves are significant source of gaseous pollutants and heat load. Indoor environmental assessments have been carried out in order to evaluate the key parameters. The aim of this studies is to develop a new design and monitoring method of residential kitchens with gas stoves. Primary results of laboratory researches indicate that the largest stovetop burner with power of 2.8 kW, has the main role. Significant emissions of NOx have been measured, in an average size kitchen (Vroom = 36 m3) the Hungarian standard NOx concentration level (200 ?g/m3) can be ensured with an exhaust air-flow of 1102 m3/h. With respect of thermal environmental parameters, heat loads of residential gas stoves could be characterized with convective heat transfer coefficient of 4.5 W/m2K and radiant heat transfer coefficient of 5.9 W/m2K. As regards thermal comfort parameters, predicted mean rate index in proved to be applicable in residential kitchens from ?0.3 to +2.0. However draught rating cannot be applied, with respect to the temperature limitations.

Assessment of indoor environment to influence the production of gosling broilers when using sanitary litter

The purpose of research and production experiment in the conditions of Akhmetov farm located in the Vysokogorsky district of the Republic of Tatarstan was to study a new sanitary litter material and the effect on the indoor environment, production, viability and feed input required to rear gosling broilers. The experiment found that the new sanitary litter material, made of thermochemically and biotechnologically processed woodworking waste, over the entire period of research was characterized by higher qualities compared to raw sawdust. Accordingly, in the end, the moisture of the said material was lower by 28.5 %, the total microbial count and numbers of microscopic fungi were less by 13.3 % and 19.9 %, respectively. The said litter material helped to improve the environment in the poultry house, which reduced harmful gases (carbon dioxide – 0.11 % and ammonia – 0.33 mg/m3), dust – 0.9 mg/m3 and microorganisms – 8.9 thousand bwt/m3. Ultimately, this contributed to a higher daily live weight gain by 7.51 % and livestock viability by 1.80 %, and, sequentially reduced feed input per 1 kg of live weight gain by 4.98 %, as compared with the control.

Associations among particulate matter, hazardous air pollutants and methane emissions from the Aliso Canyon natural gas storage facility during the 2015 blowout

In October of 2015, a large underground storage well at the Aliso Canyon natural gas storage facility experienced a massive methane leak (also referred to as “natural gas blowout”), which resulted in the largest ever anthropogenic release of methane from a single point source in the United States. Additional sampling conducted during the event revealed unique gas and particle concentrations in ambient air and a characteristic “fingerprint” of metals in the indoor dust samples similar to samples taken at the blowout site. We further investigated the association between the Aliso Canyon natural gas storage site and several measured air pollutants by: (a) conducting additional emission source studies using meteorological data and correlations between particulate matter, methane, and hazardous air pollutants (HAPs) collected during the natural gas blowout at distances ranging from 1.2 to 7.3 km due south of well SS25, (b) identifying the unique i/n-pentane ratio signature associated with emissions from the blowout event, and (c) identifying characteristics unique to the homes that tested positive for air pollutants using data collected from extensive indoor environmental assessment surveys. Results of air quality samples collected near Aliso Canyon during the final weeks of the event revealed that elevated levels of several HAP compounds were likely influenced by the active natural gas blowout. Furthermore, the final attempts to plug the well during the days preceding the well kill were associated with particle emissions likely from the well site. Together, this investigation suggests uncontrolled leaks or blowout events at natural gas storage facilities have the potential to release harmful pollutants with adverse health and environmental consequences into proximate communities. With this evidence, our recommendations include facility-specific meteorological and air quality data-collection equipment installed at natural gas storage facilities and support of environmental surveillance after severe off-normal operation events.

Classification of Potential Risk Factors through HIRARC Method in Assessing Indoor Environment of Museums

Museums were established in Malaysia more than hundred years ago. Since the year 2005, Malaysia has been moving away from constructing new buildings in favor of refurbishing historic and old ones. A healthy environment at the museum building has been identified as one of the important element that must been considered. Here, IAQ has become an important factor to provide a healthy environment in the museum building, but it is not sure either IAQ in the museum building provide a good air quality or not. So, the purpose of this study was conducted to determine the potential risk factor of the museum building by using the Potential Risk Categories, as a tool to identify the suitable location to conduct the indoor environment assessment at the museum building. Based on four mains criteria in the Potential Risk Categories, it is found that, out of 24 museum buildings, there were 8 museum buildings has been identified as a medium potential risk while 16 museum buildings are low potential risk. So, the selection of location based on Potential Risk Categories is important for the next step of indoor environment assessment at museum building, so that the most critical risk museum building could be assessed and suggestion could be provided to minimize the potential risk available in the museum building.

Effects of neighborhood building density, height, greenspace, and cleanliness on indoor environment and health of building occupants

The influences of indoor environment quality on occupant health have long been one of the main focuses in built environment and public health research. However, evidence to this effect has been inconsistent. Furthermore, previous urban studies have indicated the interaction between urban morphology and indoor environment. This study thus goes beyond indoor environment to investigate: i) the effects of neighborhood environment on occupant health; and ii) the mediating roles of indoor environment on the neighborhood environment and occupant health relationships. To achieve this aim, buildings located in different neighborhood environment in Hong Kong are selected. Data are collected by post-occupancy evaluation (occupant health), indoor environment assessment (thermal comfort, indoor air quality, ventilation, visual comfort, and acoustic comfort) and neighborhood environment assessment (neighborhood building density, building height, cleanliness and greenspace) through questionnaire survey. Through correlation analysis, regression modelling and Sobel test, it is found that: i) occupant health is significantly affected by neighborhood building height, building density and cleanliness; ii) the relationships between neighborhood environment and occupant health are significantly mediated by indoor environment, in terms of visual and acoustic comfort; and iii) neighborhood greenspace affects occupant health indirectly through influencing indoor air quality. To cross validate the results of the survey study, which is conducted using subjective data, objective measurements and analyses are further conducted. The objective study, echoing the survey study results, indicates that buildings with lower neighborhood building density and height, and cleaner neighborhood environment have better visual (higher illuminance level) and acoustic (lower noise level) performances.