Indoor Environmental Problems Research Articles

A study of thermal performance enhancement of building envelopes by using corncob as construction material

The energy-saving design of buildings effectively reduces heating energy consumption, improves indoor environmental problems in traditional houses, and plays an essential role in alleviating the increasingly severe environmental and energy problems. This study reviews the status of research on building energy-saving renovation and environmental improvement in various countries and summarizes their relevant research experiences. It described the theories and methods of survey, experiment, and numerical simulation to provide a theoretical basis for energy-saving renovation and environmental improvement of residential houses. Furthermore, it introduces corncob concrete material to provide new materials for the renovation of an old building. This research is based on the coastal Liyuan houses in Qingdao, and the problems of Liyuan houses are identified through in-field investigation. Then, through experimental simulations, the application and efficiency of corncob materials in the thermal performance improvement of the envelope are explored. The renovation of old residential houses in terms of energy-saving and environmental improvement is proposed from envelope renovation.

The development model of sustainable campus based on green buildings: a systematic comparative study between Japan and China

PurposeThe research on sustainable campus is related to environmental protection and the realization of global sustainable development goals (SDGs). Because the sustainable campus development in China and Japan is carried out around buildings, this paper takes Kitakyushu Science and Research Park as a case to study the characteristics and typical model of sustainable campus in Japan by combined with the characteristics of Chinese sustainable campus.Design/methodology/approachThis study compares the evaluation standards of green buildings between China and Japan, then compares the assessment results of the same typical green building case and finally summarizes the development mode and main realization path by discussing the implications of green buildings on campus sustainability.FindingsThe results show that (1) the sustainable campus evaluation in Japan mainly pays attention to the indoor environment, energy utilization and environmental problems. (2) Buildings mainly affect the sustainability of the campus in three aspects: construction, transportation and local. (3) The sustainable campus development model of Science and Research Park can be summarized as follows: taking green building as the core; SDGs as the goals; education as the guarantee; and the integration of industry, education and research as the characteristics.Practical implicationsIt mainly provides construction experience for other campuses around the world to coordinate the contradictions between campus buildings and the environment based on sustainable principles in their own construction. It proposes a new sustainable campus construction path of “building–region–environment” integrated development.Originality/valueThis study provides theoretical framework for the development of sustainable campuses that includes long-term construction ideas and current technological support greatly improving the operability of practical applications. It not only enriches the sample cases of global sustainable campuses but also provides new ideas and perspectives for the sustainable development research of the overall campus through quantitative evaluation of building and environmental impacts.

Determination of pressure difference coefficient of shuttle elevator doors in super high-rise buildings under stack effect

The stack-induced airflow of super high-rise buildings in winter results in obvious indoor environmental problems at the shuttle elevator shaft. Strong pressure difference can cause malfunction of elevators. The estimation of pressure differences at the shuttle elevator doors under different building layout and climate conditions is still a challenge to obtain in engineering application. Considering the difficulties of measuring and simulating the air leakage characteristics of various components, a dimensionless metric, the Pressure Difference Coefficient of Elevator Doors, Cele, is defined according to the theory of pressure distribution in buildings. First, the accuracy of the index calculation results was verified in an elevator test tower. The hand-calculated method to predict the pressure differences at the shuttle elevator doors is convenient and reliable when compared with measurement and simulation. Then, two influence factors on Cele, floor plan and flow exponents are discussed. The determination method of recommended Cele is proposed by analyzing with different building partition layers. The recommended values are given under different shaft heights and temperature difference. Moreover, the novel method and metric were applied in an actual building to determine the number and air tightness of partition layers under the target conditions. This paper provides an evaluation reference for the convenient and effective design of elevator type selection and building layout of super high-rise buildings under stack effect.

Identification of building environment problems

The indoor environment is an enclosed space where people tend to spend more and more time. Its atmosphere has a significant impact on room users. The article deals with the self – reported problems of volunteers related to the sick building syndrome (SBS). The tests were performed in the large lecture room of Kielce University of Technology, where 69 students took part in the questionnaire survey on indoor environment and health related problems. The results show that the students experienced SBS symptoms and that they might have an impact on their concentration during the lecture.

Occupational Health Problems and Lifestyle Changes Among Novice Working-From-Home Workers Amid the COVID-19 Pandemic.

BackgroundSocial distancing by working-from-home is an effective measure to decrease the spread of COVID-19. However, this new work pattern could also affect the well-being of workers. Therefore, the aim of the study was to study the magnitude of occupational health problems and lifestyle changes among workers who have only recently started working from home.MethodsA cross-sectional study was conducted using online self-administered questionnaires during the coronavirus disease 2019 pandemic in the Bangkok metropolitan area, Thailand. The participants were from any organization that allowed working from home. The demographic data including the analysis of the characteristics of working from home, the occurrence of occupational health problems, and the lifestyle changes caused by working from home were analyzed.ResultsA total of 869 workers were included as study participants. The highest prevalence of physical health problems among all workers was identified to be weight gain at a rate of 40.97% (95% confidence interval = 37.69–44.24), and the highest prevalence of psychosocial problems was identified to be cabin fever at a rate of 31.28% (95% confidence interval = 26.66–35.90%) among full-time working-from-home workers. The health effects that were significantly related to the intensity of working from home (p for trends <0.05), either positively or negatively, included body weight changes, ergonomic problems, indoor environmental problems, and psychosocial problems. Meanwhile, the lifestyle changes related to work intensity included eating pattern, sleep habits, and exercise.ConclusionsWorking from home can affect workers' well-being in various aspects. Hence, occupational health providers must prepare for risk prevention and health promotion in this “new normal” working life pattern and for future pandemics.

A Deep-Learning-based Strategy for Kidnapped Robot Problem in Similar Indoor Environment

We present a deep-learning-based strategy that only uses a 2D LiDAR sensor to solve the kidnapped robot problem in similar indoor environments. First, we converted a set of 2D laser data into an RGB-image and an occupancy grid map and stacked them into a multi-channel image. Then, a neural network structure with five convolutional layers and four fully connected layers was designed to regress the 3-DOF robot pose. Finally, the network was trained using multi-channel images as input. We also improved the network structure to identify the scene where the robot is localized. Extensive experiments have been conducted in practice with a real mobile robot, verifying the effectiveness of the proposed strategy. Our network can obtain approximately 2m and 5∘ accuracy indoors, and the scene classification accuracy of our network reaches up to 98%.

Analysis of the Importance of Fresh Air System to Indoor Environment of Green Building and Healthy Building

As an important place for people to live, study and work, the building indoor environment has gradually become the focus of people’s attention. The fresh air system plays an important role in improving indoor environmental health problems. This paper discusses the control requirements of green buildings and healthy buildings on the indoor environment. Through the real-time detection of the indoor environment temperature, relative humidity, CO2 concentration, PM2.5 concentration, air flow speed and fresh air volume of the building, the operation process of the fresh air system is analyzed. The impact on the indoor environment, expounds the importance of the fresh air system to the indoor environment, and provides a reference for the improvement of the indoor environment of green buildings and healthy buildings.

Indoor Localization Algorithm Based on Array Antenna and Sparse Bayesian Learning

Due to the influence of many factors such as multipath and multi-source, the traditional indoor localization algorithms based on Bluetooth signal strength have low performance in accuracy and stability. In order to solve the location problem in complex indoor environment based on Bluetooth signal, an indoor localization algorithm based on low-cost array antenna is developed. The algorithm utilizes single-channel using switch-antenna polarization sensitive array to sample Bluetooth signal, then combines the accurate array manifold measured in dark room and the algorithm of Polarized Fast Converging Sparse Bayesian Learning (P-FCSBL) to estimate the source’s angle, and finally gets the target location by angle. This algorithm makes full use of polarization information and angle information to separate target and multipath signal, and simultaneous sampling of one source ensures estimation stability. Finally, the effectiveness of the method is verified by the real data.

Identifying stack-driven indoor environmental problems and associated pressure difference in high-rise residential buildings: Airflow noise and draft

Building airflow is a main factor in indoor air and environmental qualities. In particular, stack-induced airflow can cause indoor environmental problems in high-rise buildings over the winter due to the strong driving force (pressure difference). The goal of this study was to identify the actual characteristics of stack-driven environmental problems in real high-rise residential buildings through a field survey and airflow simulation. We collected the actual resident complaints (140 cases) raised in six high-rise residential buildings in South Korea during three years. The most frequent complaints were airflow noise and drafts at residential entrance doors. Then, by a calibrated airflow simulation, we identified the unknown pressure differences that caused these two problems. Based on the pressure differences, this study could determine problem occurrence rates for noise and drafts depending on given pressure differences. Apart from the existing allowable or reference pressure difference (50 Pa) across doors suggested by ASHRAE and European standards (EN 12101-6), which is related to emergency escape, three reference levels were suggested: (1) tight: 25 Pa, (2) normal: 40 Pa, and (3) loose: 65 Pa. These values were intended to be used as the reference in predicting or solving the stack-driven problems. Finally, we successfully predicted the frequency of these problem occurrences over the winter in a target building, using a coupled airflow and thermal simulation. These results showed the importance of the newly suggested references, 25 Pa or 40 Pa rather than 50 Pa, in identifying the stack-driven airflow noise and draft.

Characterizing dynamic relationships between burning rate and pollutant emission rates in a forced-draft gasifier stove consuming biomass pellet fuels

Biomass is a dominant solid fuel type worldwide. Traditional biomass combustion leads to severe indoor and ambient environmental problems. Biomass pellet utilization in forced-draft gasifier stoves is regarded as an improved approach to these problems. Previous studies on forced-draft biomass stoves mainly considered average emission amounts and lacked details of the combustion properties and dynamic correlations between emissions and combustion. This study used a dynamic measurement system to test a typical forced-draft gasifier stove consuming wood pellets and maize straw pellets. Real-time fuel burning rate, that partly reflects the combustion performance, and CO, NOx and PM2.5 emission rates, over a whole combustion course, were monitored. In all tests, the burning rate rose to a high and stable level, and then sharply subsided. CO, NOx and PM2.5 emission rates varied across the combustion course. CO (NOx) emissions have a negative (positive) logarithmic linear relationship with burning rate, while no consistent relationship was observed for PM2.5 emission rate. The identified relationships between burning rate and pollutant emission rates suggest the possibility of estimating emission performance of forced-draft biomass pellet stoves based on combustion indicators, or vice versa.

Feasibility study on mental health‐care effects of plant installations in office spaces

AbstractOffices may have different indoor environmental quality related problems, such as space, indoor air quality, office workers’ thermal comfort, productivity, and mental stress. The objective of this study was to examine the effect of indoor plants on physiological/psychological responses and productivity, and to examine the mental healthcare status of office workers. To clarify the effect of indoor plants, we conducted a demonstration experiment in two rooms of an office. The experiment was performed in two office spaces (Office A and Office B) located in Kyoto, Japan. Office A was a call center and Office B was a general office. Subjects were office workers working in one of the above two office spaces. In the experiment, nine cycles were conducted while changing the type of plants including vegetables and foliage plants. A preliminary experiment without plants was conducted as a reference case. Results indicated that plant installations in office spaces have certain mental health‐care effects, namely, relaxation of visual fatigue and the feelings of drowsiness of five groups of work‐related fatigue feelings, and the effects by installations of plants depend on the type of plant and industry, although this study had some limitations because of the demonstration experiment.

Investigation of indoor environment comfort in large high-speed railway stations in Northern China

The indoor environment of high-speed railway stations is more complex than in traditional railway stations. This could lead to complex indoor environment problems. In this study, indoor environmental measurements and passenger satisfaction surveys were conducted in two high-speed railway stations in summer and winter, considering the indoor thermal, natural light, acoustic and air environment. The results indicate that the air temperatures in winter were far below comfort standards. The mean illuminance met the standard requirements in both stations. However, the illuminance uniformity was very low in the summer. The acoustic and air environments were satisfactory and have positive impacts on the overall environmental comfort of passengers. The evaluated acoustic environment indicated this has a worst effect on passengers’ comfort. The depth of the waiting halls affected the air environment. The subjective survey revealed the following: Females were more sensitive to the indoor environment than males in winter. Northerners were more satisfied with the environment than Southerners. Older passengers were slightly more tolerant to the environment. Passengers with a longer waiting time would have higher demands for a better indoor environment. Also, passengers were more tolerant in summer than in winter.

Indoor Path Planning using Harmonic Functions via Half-Sweep Arithmetic Mean Method

This paper presents the application of a two-stage Half-Sweep Arithmetic Mean (HSAM) iterative method to obtain the Harmonic functions to solve the path planning problem in a 2D indoor environment. Several path planning simulations in a known indoor environment were conducted to examine the effectiveness of the proposed method. It is shown that the proposed path planning algorithm is capable of generating smooth paths from various start and goal positions. Also, numerical results show that the proposed HSAM method converges much faster than the existing iterative methods, thus it drastically improves the overall performance of the path planning algorithm

A Study on the Simulation Result of Horizontal Shading Installation for Passive Cooling of Building South KOREA

In South Korea, the evaluation criteria for the shading devices installation are defined by regulations, but the standards of design methods are not clearly established. The installation of shading device is used to solar control in building. It has become mandatory for some public buildings due to revised regulations. Generally this device mean is horizontal shading at upper window. Therefore, a design of horizontal shading device which takes into account the energy consumption of the building is required, and indoor environmental problems which may occur due to the installation of them should also be taken into consideration. This research studied to propose a design which takes into account the energy consumption which may occur if the horizontal shading device is installed, and suggest an improved design method of horizontal shading devices on the basis of the analysis of the problems that may occur when they are installed. Consequently, it was confirmed that as the length of the horizontal shading device becomes longer, the incoming daylight is reduced and the indoor intensity of illumination becomes lower, and thus, more lighting energy may be consumed in a room where the shading device is installed than in the one where it is not. Therefore, annual energy consumption was calculated by applying the lighting control and it was found that the total energy consumption decreased as a result of the reduction in energy consumption for air conditioning and fans and further decrease in lighting energy consumption.

Association between Environmental Factors in Home and Behavioral Problems in Children with Allergic Diseases: Based on 2015 Panel Study of Korean Children Survey

Purpose: This study aimed to investigate the association between indoor environmental exposures and behavioral problems in children with allergic diseases. Methods: We used data from 2015 Panel Study of Korean Children (PSKC). The subjects of this study included 825 children aged 7 years with asthma, allergic rhinitis, or atopic dermatitis. The data was analyzed using hierarchical multiple regression. Results: Factors influencing behavioral problems in children with allergic diseases were passive smoking (β=.15, p<.001), painting from 1year after birth until 1 year ago (β=.13, p<.001), using of linoleum as floor materials (β=.09, p<.001), change of wallpaper From 2 years before pregnancy until 1year after birth (β=.08, p<.001), change of wallpaper from 1year after birth until 1 year ago (β=.07, p<.001), keeping hot food or water in plastic container (β=.06, p<.001), remodeling from 1 year after birth until 1year ago (β=.04, p<.001), using of plastic container (β=.03, p<.001), and change of floor materials from 1 year after birth until 1year ago (β=.01, p=.006) which explained about 10% of behavioral problems. Conclusion: This study showed that indoor environmental exposures were associated with behavioral problems in children with allergic diseases. Based on the findings of this study, programs focusing on controlling of indoor environmental exposures may help to prevent and reduce behavioral problems in children with allergic diseases.

Implications of Different Household Cooking Energy on Indoor Air Quality in Urban and Semi-Urban Settlements in Imo, South Eastern Nigeria

Energy is a basic necessity of life for meeting domestic, social and industrial needs of man. But the use of some of the energy sources has created problems in indoor environment that requires urgent attention. This study assessed the indoor air quality status as regards the effect of different household cooking methods from the use of nonrenewable energy sources in parts of Imo State. The cooking methods sampled were firewood stove, kerosene stove, charcoal stove, electricity stove and gas cooker. Indoor air quality was measured by digital air analyzers of different models continuously for 24 hours. Data collected were subjected to ANOVA using the SPSS 12.0 software, and mean values separated with FLSD) at P<0.05 as statistically significant. Results showed that CO and PM 2.5 concentrations produced during the use of firewood stove in urban settlements recorded the mean (313.94± 21.77 and 476.06±203.09 and semi- urban settlement (320.48±25.03and 562.38±174.87. The overall mean indoor air pollutants in urban and semi-urban environment were in order of : SO 2 ≥CO ≥PM 2.5 ≥NO 2 respectively, with CO, SO 2 and PM 2.5 being above the 100 (μg/m³), 80 (μg/m³) and 150(μg/m³) NAQS-2006 IAQ. Indoor air qualities from cooking methods in urban and semi-urban are statistically different at (P < 0.05) level. The findings further indicated that gas cooker and electric stove cooking methods have less harmful effects than fuel wood, charcoal and kerosene on the indoor air quality in the study area. This indicated that urban and semi-urban settlements were utilizing energy sources at the lower energy ladder, with fuel wood dominating. Based on the findings, cleaner energy sources should be used in order to reduce indoor air pollution in developing countries.

Dampness and Moisture Problems in Norwegian Homes.

The occurrence of dampness and mold in the indoor environment is associated with respiratory-related disease outcomes. Thus, it is pertinent to know the magnitude of such indoor environment problems to be able to estimate the potential health impact in the population. In the present study, the moisture damage in 10,112 Norwegian dwellings was recorded based on building inspection reports. The levels of moisture damage were graded based on a condition class (CC), where CC0 is immaculate and CC1 acceptable (actions not required), while CC2 and CC3 indicate increased levels of damage that requires action. Of the 10,112 dwellings investigated, 3125 had verified moisture or mold damage. This amounts to 31% of the surveyed dwellings. Of these, 27% had CC2 as the worst grade, whereas 4% had CC3 as the worst grade level. The room types and building structures most prone to moisture damage were (in rank order) crawl spaces, basements, un-insulated attics, cooling rooms, and bathrooms. The high proportion of homes with moisture damage indicate a possible risk for respiratory diseases in a relatively large number of individuals, even if only the more extensive moisture damages and those located in rooms where occupants spend the majority of their time would have a significant influence on adverse health effects.

Air-Sense: indoor environment monitoring evaluation system based on ZigBee network

In the modern life, people spend most of their time indoors. However, indoor environmental quality problems have always been affecting people’s social activities. In general, indoor environmental quality is also related to our indoor activities. Since most of the organic irritants and volatile gases are colorless, odorless and too tiny to be seen, because we have been unconsciously overlooked indoor environment quality. Consequently, our body suffer a great health problem. In this work, we propose Air-Sense system which utilizes the platform of ZigBee Network to collect and detect the real-time indoor environment quality. What’s more, Air-Sense system can also provide data analysis, and visualizing the results of the indoor environment to the user.

Analyzing symptom data in indoor air questionnaires for primary schools.

Questionnaires on symptoms and perceived quality of indoor environment are used to assess indoor environment problems, but mainly among adults. The aim of this article was to explore best ways to analyze and report such symptom data, as part of a project to develop a parent-administered indoor air questionnaire for primary school pupils. Indoor air questionnaire with 25 questions on child's symptoms in the last 4weeks was sent to parents in five primary schools with indoor air problems and in five control schools. About 83% of parents (N=1470) in case schools and 82% (N=805) in control schools returned the questionnaire. In two schools, 351 (52%) parents answered the questionnaire twice with a 2-week interval. Based on prevalence of symptoms, their test-retest repeatability (ICC), and on principal component analysis (PCA), the number of symptoms was reduced to 17 and six symptoms scores were developed. Six variants of these six symptom scores were then formed and their ability to rank schools compared. Four symptom scores (respiratory, lower respiratory, eye, and general symptoms) analyzed dichotomized maintained sufficiently well the diversity of symptom data and captured the between-school differences in symptom prevalence, when compared to more complex and numerous scores.

A Study on the Effectiveness of the Horizontal Shading Device Installation for Passive Control of Buildings in South Korea

In South Korea, the evaluation criteria for installing shading devices are defined by regulations, but the standards of design methods are not clearly established. The installation of shading devices has become mandatory for some public buildings due to revised regulations. Therefore, a design of horizontal shading device is required, and indoor environmental problems which may occur due to their installation should also be taken into consideration. This research aimed to propose a design which takes into account the energy consumption which may occur if the horizontal shading device is installed and suggests an improved design method of horizontal shading devices when they are installed. Consequently, it was confirmed that as the protrusion of the horizontal shading device becomes longer, the incoming daylight is reduced and the indoor intensity of illumination becomes lower, and thus more lighting energy may be consumed in a room where the shading device is installed than in the one where it is not. Therefore, annual energy consumption was calculated by applying the lighting control and it was found that the total energy consumption decreased by the reduction of air-conditioning and fans and lighting energy consumption.