Indoor Air Quality Parameters Research Articles

Real-World Implementation of an ICT-Based Platform to Promote Energy Efficiency

The energy efficiency requirements of most energy-consuming sectors have increased recently in response to climate change. For buildings, this means targeting both facility managers and building users with the aim of identifying potential energy savings and encouraging more energy-responsible behaviors. The Information and Communication Technology (ICT) platform developed in Horizon 2020 FEEdBACk project intends to fulfill these goals by enabling the optimization of energy consumption, generation, and storage and control of flexible devices without compromising comfort levels and indoor air quality parameters. This work aims to demonstrate the real-world implementation and functionality of the ICT platform composed of Load Disaggregation, Net Load Forecast, Occupancy Forecast, Automation Manager, and Behavior Predictor applications. Particularly, the results obtained by individual applications during the test phase are presented alongside the specific metrics used to evaluate their performance.

Passive cooling and natural ventilation by the windcatcher (Badgir): An experimental and simulation study of indoor air quality, thermal comfort and passive cooling power

The upper wing wall can be integrated into the windcatcher to prevent direct solar and rain penetration. The impact of this combination was not considered in previous studies. Moreover, analyzing adaptive thermal comfort is another gap that was not addressed by preceding windcatcher studies, particularly for the tropical climate. Therefore, the current research aims to evaluate a two-sided windcatcher incorporated with the upper wing wall from two views: indoor air quality (IAQ) and adaptive thermal comfort. A small-scale model was tested in the wind tunnel. Next, CFD models were validated against experimental data with a good agreement between the two methods. Windcatchers with different upper wing wall lengths ranging between 10 cm and 50 cm were assessed. The results showed that the length increase led to a slight increase in the ventilation rate, and the best performance was seen in the 50 cm configuration. Subsequently, IAQ and adaptive thermal comfort were evaluated at different wind speeds of this climate. The results demonstrated that even in wind speeds below the annual average (2.5 m/s), the windcatcher performance can still satisfy IAQ parameters such as airflow rate and air change rate, recommend by CIBSE Guide A. In addition, based on the simulated conditions the results showed that wind speed from 2.5 m/s to 4 m/s could provide thermal comfort within 50%–80% of the ventilated space. Finally, the estimation of passive cooling power showed that windcatcher could provide a maximum (9.6 kW) cooling power if the wind speed is at 4 m/s and outdoor temperature at 23 °C.

FEEdBACk: An ICT-Based Platform to Increase Energy Efficiency through Buildings’ Consumer Engagement

Energy efficiency in buildings can be enhanced by several actions: encouraging users to comprehend and then adopt more energy-efficient behaviors; aiding building managers in maximizing energy savings; and using automation to optimize energy consumption, generation, and storage of controllable and flexible devices without compromising comfort levels and indoor air-quality parameters. This paper proposes an integrated Information and communications technology (ICT) based platform addressing all these factors. The gamification platform is embedded in the ICT platform along with an interactive energy management system, which aids interested stakeholders in optimizing “when and at which rate” energy should be buffered and consumed, with several advantages, such as reducing peak load, maximizing local renewable energy consumption, and delivering more efficient use of the resources available in individual buildings or blocks of buildings. This system also interacts with an automation manager and a users’ behavior predictor application. The work was developed in the Horizon 2020 FEEdBACk (Fostering Energy Efficiency and BehAvioral Change through ICT) project.

Indoor air quality and the associated health risk in primary school buildings in Central Europe - The InAirQ study.

The indoor air quality (IAQ) was investigated in sixty-four primary school buildings in five Central European countries (Czech Republic, Hungary, Italy, Poland, and Slovenia). The concentration of volatile organic compounds, aldehydes, PM2.5 mass, carbon dioxide, radon, as well as physical parameters were investigated during the heating period of 2017/2018. Significant differences were identified for the majority of the investigated IAQ parameters across the countries. The median indoor/outdoor ratios varied considerably. A comprehensive evaluation of IAQ in terms of potential health effects and comfort perception was performed. Hazard quotient values were below the threshold value of 1 with one exception. In contrast, 31% of the school buildings were characterized by hazard index values higher than 1. The maximum cumulative ratio approach highlighted that the concern for non-carcinogenic health effects was either low or the health risk was driven by more substances. The median excess lifetime cancer risk values exceeded the acceptable value of 1×10-6 in the case of radon and formaldehyde. PM2.5 mass concentration values exceeded the 24h and annual guideline values set by the World Health Organization in 56 and 85% of the cases, respectively. About 80% of the schools could not manage to comply with the recommended concentration value for carbon dioxide (1000ppm).

Implications of portable gasoline electricity generators on residential indoor air quality

Introduction: Toxic gases emitted from electricity generating plants used for energy production process diffuse in the environment thereby causing environmental air pollution. The effect of the installation and usage of portable gasoline electricity generating plants at the balcony of different households on the indoor air quality was assessed in this study. Materials and methods: The data collected were the air quality chemical composition variables which include carbon-dioxide, formaldehyde, total volatile organic compounds, coarse (PM10), and fine (PM2.5) particulate matters at the indoor of the households in Abeokuta metropolis, Ogun state, Nigeria. Physical measurement techniques used for the data collection was through the instrumentation design of two air quality testers, models WP6910 and ZN-202S. The indoor air quality assessment followed the generator nighttime usage routine between the hours of 6:30 – 10:00 pm at a measurement height of 1.3 m and the center in the living rooms of the residences assessed. Results: The analysis of the data obtained showed that the mean values for each of the air quality parameters obtained during generator usages were significantly higher when compared to the indoor air quality parameters before generator usages at p<0.05. The air pollutant levels before and during generator usages were within the established safe standard air quality limit by the world health organization. Conclusion: However, for the installation of a portable electricity generator at the residents’ balcony, it is recommended that the generators should be adapted with an emission reduction device for the exhaust composition amelioration to avoid possible accumulation effect over time.

A Random Forest Classification Algorithm Based Personal Thermal Sensation Model for Personalized Conditioning System in Office Buildings

Abstract The personal thermal sensation model is used as the main component for personalized conditioning system, which is an effective method to fulfill thermal comfort requirements of the occupants, considering the energy consumption. The Random Forest classification algorithm based thermal sensation model is developed in this study, which combines indoor air quality parameters, personal information, physiological factors and occupancy preferences on selection of 7-level of sensation: cold, cool, slightly cool, neutral, slightly warm, warm and hot. Our model shows better functionality, as well as performance and factor selection. As a result, our method has achieved 70.2% accuracy, comparing with the 57.4% accuracy of support vector machine, and 67.7% accuracy of neutral network in an ASHRAE RP-884 database. Therefore, our newly developed model can be used in personalized thermal adjustment systems with intelligent control functions.

Development of mathematical model to study the effect of indoor air quality parameters and optimization using response surface methodology

This paper explores opportunities to know about the optimal setting and influencing parameters of Indoor Air Quality characteristics (IAQ) of the air-conditioned car by response surface methodology (RSM). The trials were designed by the design of experiments and performed to cram the result of input parameters i.e human load, fresh air supply, and air velocity, on the Indoor Air Quality parameters i.e Temperature, Relative humidity, Oxygen and carbon dioxide inside the car air-conditioned space. This work traveled around on finding the mathematical model to show a relationship and interactions of IAQ parameters. Also, this work focused on finding the optimum setting controlling parameters by RSM. It recommend that car AC setting position of fresh air supply knob, and Air velocity (blower speed knob) for different human loads. This study be evidence for that the Response Surface methodology (RSM) techniques were suitable for optimizing the IAQ parameters with the minimum number of trials.

BIM for Healthy Buildings: An Integrated Approach of Architectural Design based on IAQ Prediction

The relationship between users and the built environment represents a fundamental aspect of health. The factors that define the properties linked to health and well-being are increasingly becoming part of building design. In these terms, building information modelling (BIM) and BIM-based performance simulation take on a priority role. Among the key features for the design of Healthy Buildings, indoor air quality (IAQ) plays a central role. There are numerous indoor pollutants with significant health effects; volatile organic compounds (VOCs) are to be mentioned among these. The paper presents the proposal of an integrated workflow in the BIM process for the check and control of VOC emissions from building materials and their concentration in confined environments. The workflow is developed through the systematisation of IAQ parameters for the open BIM standard, the integration in the BIM process of a numerical model for the prediction of the VOCs concentration in the indoor environment, and the development of model checkers for performance verification. The results show a good adhesion between the numerical model and the implementation in BIM, providing the designer with a rapid control instrument of IAQ in the various phases of the building design. The present study is the first development focused on TVOC, but implementable concerning other aspects of IAQ, as needed for the effectiveness of performance building-based design for health and wellness issues.

Association between Indoor Air Quality Parameters (PM2.5, CO2, and Bioaerosols) in Children Day Care Centres with and without Air Purifier in Bangi.

Introduction: The use of air purifiers have been demonstrated to reduce the level of indoor air quality (IAQ) parameters, thus these may give beneficial effects to the human health. Studies on the effectivity of air purifier in the indoor settings are still limited especially in sensitive environmental settings such as daycare centres. Objective: This study aims to determine the concentration of IAQ parameters between daycare centres with and without the use of an air purifier. Methodology: Purposive sampling was used in selecting the daycare centre with (DC3) and without air purifier (DC1 and DC2) within Bangi areas. The walkthrough inspection was conducted and 5 parameters of IAQ including PM2.5, CO2, bioaerosol (bacterial and fungal), relative humidity and temperature were assessed in this study. A standardized and modified questionnaire adopted from The International Study of Asthma and Allergies in Childhood (ISAAC) was distributed to 46 parents to assess sociodemographic and respiratory symptoms among their children. Result: The result showed that there is a significant difference between PM2.5, CO2, bacteria and fungi concentration in studied areas. Daycare centres with air purifiers (DC3) found the lowest concentration of PM2.5 (18.2 µg/m3) and bacterial count (148 CFU/m3) except for fungal counts and CO2 level. The finding showed that PM2.5 in daycare centres without air purifier (DC1) had the highest (39.1µg/m3). All IAQ parameters not exceed the National Ambient Air Quality (NAAQs) and Department of Occupational, Safety and Health (DOSH) standards. All respiratory symptoms showed no significant difference between daycare with and without air purifier except for asthma symptoms. The higher number of children in the DCs without air purifiers experiences a productive cough and allergic reaction compared to the DC with an air purifier. Conclusion: The finding suggests that the daycare centers with air purifiers can improve IAQ and lower the risk of respiratory symptoms among the centre’s building occupants.

Indoor Climate as a Service: a digitalized approach to building performance management

Digitalization provides significant opportunities for innovation, new business models, and services for the building sector. This paper describes the implementation of a concept for providing “Indoor Climate as a Service”, based on a case study of digital transformation in a modern office building. This concept can accelerate the energy savings and reduce power demand in the existing building stock by implementing digitalization (sensors and actuation, together with data integration and analytics platform), and providing full incitements for energy investments at the same time as the contracted indoor climate is secured and verified using real-time data. The digital transformation included obtaining data from different sub-systems (climate control, IoT-devices and Space booking system etc.), applying the RealEstateCore ontology to organize the data, and the development of an IoT-Edge computing solution. A key objective of this study is to explore the types and quality of data (for example, from sensor signals) needed to implement the concept in a modern office building. Key indoor air quality and energy performance control parameters were analyzed with relevance to developing a robust business model. The results of the study demonstrate the significant potential of utilizing digital infrastructures for implementing Indoor Climate as a Service.

Study of the measured and perceived indoor air quality in Swedish school classrooms

The influence of a classroom’s indoor environment on children’s health, performance and comfort is a concern that receives increasing attention. Many schools experience problems with inadequate indoor air quality and climate. Investigations of the indoor air quality (IAQ) in schools have been often non-systematic, which can lead to costly ad-hoc remediation actions. It is therefore important to develop a holistic approach to the assessment of IAQ in schools.This paper presents a field study on the indoor air quality and thermal environment conditions of elementary schools in Gothenburg, Sweden. The focus of the paper is on the methodology to investigate the IAQ using both objective measurements and subjective assessment of the perceived IAQ. The indoor environmental measurements include indoor air quality and thermal comfort parameters for which guideline values exist. Finally, a questionnaire was developed to evaluate the perception of the classroom’s thermal environment and air quality by young children.The paper presents the study protocol and diagnostics approach for IAQ in classrooms. Examples of results from the first 10 investigated classrooms are presented.

Prevalence and risk factors for respiratory symptoms among children at child care centers in Malaysia

Many studies have been conducted to assess the effects of indoor air quality (IAQ) on human health. However, there is still a lack of studies available about the adverse health effects on children’s respiratory health at Child Care Centers (CCC). The aim of this paper was to investigate the risk factors for respiratory symptoms and identify the root cause of IAQ problems at CCCs in Malaysia. The Modified American Thoracic Society and the Division of Lung Diseases (ATS-DLD-82) questionnaire was used to gather information from parents regarding their children’s respiratory symptoms. The IAQ parameters measured were for air temperature, humidity, carbon dioxide, carbon monoxide, respirable particles (PM2.5), viable bacteria and fungi count while the information on CCC characteristics and potential surrounding air pollutants were collected via a combination of area monitoring, inspection and interviews. Factors found to be significantly associated with persistent cough and/or cold were age, type of ventilation, location of CCC, floor area per child (<3.5 m2) and temperature. Children attending CCCs supplied by ACMV had the highest risk for prevalence of persistent productive cough [5.56 (CI: 2.20; 14.00)]. This study provided the baseline data on IAQ and possible factors that influenced indoor air contaminants, which could aid policy makers in formulating guidelines on IAQ for CCC in Malaysia.

Investigation of indoor air quality and thermal comfort condition in airport terminal buildings

PurposeThis paper aims to measure the thermal comfort conditions and indoor air quality parameters, through on-site measurements taken in the areas mostly occupied by the passengers and airport staff. Terminal buildings consist of areas with various functions. Heating, ventilation and air conditioning requirements vary from area to area, thus leading to challenges in the management of indoor environment quality. Therefore, the study focuses on investigating the indoor environment conditions in various areas of the terminal buildings.Design/methodology/approachIn this study, the thermal comfort and indoor air quality were evaluated based on the parameters [CO2 concentration, relative humidity, temperature, predicted mean vote (PMV) and predicted percentage of dissatisfied (PPD)] collected for summer 2019 from different zones inside the International Dalaman Airport terminal building located in the southwest of Turkey. The measurements were performed in the areas mostly occupied by the airport staff and passengers (check-in area, security control areas, international departure lounge, domestic departure lounge and baggage claim hall).FindingsAs a result of the study, it was observed that the CO2 concentration was 480–965 ppm, the relative humidity was 51.9–75.8% and the temperature was in the range of 23.9°C–28.3°C inside the airport terminal. The PMV values were determined to be in the range of −0.23 to 0.67, and the PPD values 5–15%, which are used to measure the thermal comfort conditions.Originality/valueThere has been limited study on the determination of the indoor air quality in airport terminals and the investigation of the thermal comfort conditions. However, in this study, indoor air quality and thermal comfort conditions were determined by on-site measurements in the five mostly occupied areas by passengers and employees in the terminal building.

Indoor air quality monitoring universal device

This paper presents a solution for indoor air quality monitoring universal device. Existing devices on the market analyze a small number of indoor air quality parameters, require expensive consumables and periodic maintenance services. Our solution has a small volume, portable, easy to use, low price, almost non-existent maintenance, possibility monitoring a wide range of compounds and harmful elements of air. The proposed device can be equipped with a wide variety of sensors: gas sensor, digital gas sensor for air quality breakout, combined temperature and barometric pressure sensor, a 3 sensor device suitable for gas leak detection air quality monitoring. The results obtained with this device are: the individual values for each monitored element, local and online visualization of the data, the alarms for exceeding values, online access to data for analysis and processing. Finally, the solution proposed by us is cheap, we can work continuously, with the mention that if defects occur they can be remedied quickly by replacing the parts with replacement ones, without requiring periods of interruptions in the monitoring process.

Exploring Volatile Organic Compound Exposure and Its Association with Wheezing in Children under 36 Months: A Cross-Sectional Study in South Lisbon, Portugal.

Air quality and other environmental factors are gaining importance in public health policies. Some volatile organic compounds (VOCs) have been associated with asthma and symptoms of respiratory disease such as wheezing. The aim of this study was to measure the concentration of Total VOCs and assess their possible association with the occurrence of wheezing episodes in children under 36 months of age, in a region south of Lisbon, Portugal. A cross-sectional study was performed from October 2015 to March 2016. The sample of children under 36 months of age was selected by convenience, by inviting parents to take part in the study. A survey was applied to collect information on bedroom features, as well as to verify the occurrence of wheezing episodes. The indoor air quality parameters of bedrooms were measured using three 3M Quest® EVM-7 environmental monitors. In total, 34.4% of infants had had wheezing episodes since birth, with 86.7% of these presenting at least one episode in the previous 12 months. Total VOC levels were above the reference values in 48% of the analyzed bedrooms. No significant association of VOC exposure in a domestic setting with episodes of wheezing was found. However, children living in households with smokers were 4 times more likely to develop wheezing episodes. Thus, this study provides relevant information that warrants further studies to assess infant exposure to indoor air pollution and parental smoking in a residential context.

A long-term multi-parametric monitoring study: Indoor air quality (IAQ) and the sources of the pollutants, prevalence of sick building syndrome (SBS) symptoms, and respiratory health indicators

Poor indoor air quality (IAQ) can cause several respiratory diseases and symptoms. In this study, IAQ of 121 homes located in 3 different towns of Çanakkale, Turkey was monitored throughout a year. Target air pollutants were particulate matter, volatile organic compounds (VOCs), bioaerosols, and Carbon dioxide (CO2), as well as air temperature and humidity. Moreover, pulmonary functions of the occupants were measured on a monthly basis. Also, occurrence of sick building syndrome (SBS) symptoms and other health related data were gathered from the occupants by a detailed questionnaire. The SBS is a situation related to indoor air pollution in which the occupants of a building experience health or comfort related adverse effects that appear to be associated directly to the time spent in the “sick” building. Results of this study showed that the highest indoor air pollutant levels were observed in Çan town and the lowest levels were observed in Central town. Indoor levels of bioaerosols, particulate matter, benzene, Cladosporium spp., and Penicillium spp. as well as pulmonary functions of the occupants showed statistically significant differences between the locations of the homes (p < 0.001). Factor analysis implied that both indoor and outdoor originated sources contributed to IAQ. Even though the predominant SBS symptoms varied seasonally and spatially among the study sites, fatigue, cold-flu like symptoms, and difficulty in concentration occurred frequently. Correlations were found among the occurrence of SBS symptoms, measured IAQ parameters, and personal factors (p < 0.05). Performing more studies from the health and IAQ points of view improve public awareness.

Associations of barn air quality parameters with ultrasonographic lung lesions, airway inflammation and infection in group-housed calves

Barn climate is believed to play a major role in the bovine respiratory disease complex. However, the exact air quality parameters associated with (sub)clinical pneumonia or airway inflammation in calves are currently unknown. The objective of this cross-sectional study was to assess associations of air quality parameters with clinical signs, lung consolidation, pulmonary inflammation and infection in group-housed calves. In total, 60 beef and dairy farms were visited from January to April 2017 and 428 calves sampled. Measured air quality parameters included continuous 24-h measurements of ammonia concentration, relative humidity and temperature and punctual measurements of air velocity, ammonia, CO2 and bacterial air load. Calf sampling consisted of clinical examination, thoracic ultrasonography and broncho-alveolar lavage sampling for bacteriological and cytological analysis of broncho-alveolar lavage fluid (BALf). Average air temperature was 14.2 °C (standard deviation (SD) 4.4, range 5.5–23.9) and relative humidity 68.8 % (SD 8.9, range 52.2–91.6). Average ammonia concentration was 1.7 ppm (SD 0.9, range 0–10.0). Lung consolidations of ≥1 cm, ≥3 cm and ≥6 cm in depth were present in 41.1 % (176/428), 27.1 % (116/428) and 16.1 % (69/428) of the calves, respectively. Average pen temperature was positively associated with consolidations of ≥1 cm (P = 0.005), ≥3 cm (P = 0.002) and ≥6 cm (P < 0.01). Ammonia exposure, in hours>4 ppm, was associated with lung consolidation ≥1 cm (odds ratio (OR) = 1.73; confidence interval (CI) = 1.02–3.07; P = 0.04). Ammonia concentration was positively associated with BALf epithelial cell percentage (P = 0.01). Air velocity >0.8 m/s was associated with increased odds of lung consolidation of ≥3 cm (OR = 6.8; CI = 1.2–38.5; P = 0.04) and ≥6 cm (OR = 15.9; CI = 1.2–200.0; P = 0.03). The prevalence of lung consolidations ≥1 cm was higher in the draught (81.8 %; P = 0.0092) and warm, dry and ammonia accumulation clusters (54.2 %; P = 0.02) compared to the presumably normal cluster (31.6 %). In addition, in the warm, dry and ammonia cluster the prevalence of lung consolidations ≥3 cm (38.1 %; P = 0.04) and ≥6 cm (31.4 %; P = 0.01) in depth were higher compared to the presumably normal climate cluster (18.2 % and 9.1 %, respectively). Of all frequently measured indoor air quality parameters, only average temperature, ammonia concentration and air velocity were associated with pneumonia and might therefore be preferable for cost-effective evaluation of calf barn climate.

Seasonal variations in indoor air quality parameters and occupants self-reported physical health within a warm humid climatic environment

This study examines seasonal variations in Indoor Air Quality in occupied spaces within student hostels of Obafemi Awolowo University, Nigeria, and the associated physical health effects reported by occupants. Indoor Air Quality data were obtained from 22 selected rooms, with at least two rooms selected from the nine different spatial design layouts identified in the hostel buildings. Indoor Air Quality parameters obtained were 15-minute interval data of relative humidity, as well as concentrations of carbon dioxide, total volatile organic compounds, and particulate matters. These were measured with data loggers placed at 1.0 m from the floor level in the centre of selected rooms. Measurements were taken in selected rooms through a period of four consecutive weeks each during the peaks of dry and wet seasons. A questionnaire, which was administered immediately at the end of the measurement period to 696 respondents, was used to capture the significant physical health symptoms as reported by the occupants, as well as information regarding their activities and use of the rooms. Significant health symptoms reported by occupants were the same across seasons. These were cold, fatigue, and headache. Indoor concentrations of carbon dioxide and particulate matters have most significant relationship with reported health symptoms.

Carbon Dioxide Human Gains—A New Approach of the Estimation

Human health is dependent on the Indoor Air Quality (IAQ) of residential and public buildings, where people spend a substantial amount of time. Part of IAQ parameters, like temperature or humidity influence the thermal comfort of users, whereas too high carbon dioxide concentration (CO2) could cause various complaints or diseases. In buildings like offices and schools, where we have a brush with a high density of users, the main source of CO2 is simply people. The type of their activity brings higher or lower carbon dioxide gains, that must be taken into account to design and properly use room ventilation, allowing recommended CO2 levels not to be exceeded. This paper presents an approach to marking human CO2 generation off by using an experimental method. The method was verified based on measuring results of six test series conducted in different types of rooms at Bialystok University of Technology (Poland) during lectures, meetings, projects and laboratories. Carbon dioxide gains were comparable with an average value of 0.0045 L/s, which corresponds to theoretical CO2 generation rates that are symptomatic of males and females, between 16 and 30 years old, with low physical activity.

Assessment of indoor air quality parameters at Ambulatory Care Centre XYZ, Malaysia

Indoor Air Quality (IAQ) problems are very important and necessary to consider in hospital and health care facilities such as in AMBULATORY CARE CENTRE XYZ (ACCXYZ), Malaysia. Majority complaints made by the hospital staff at level 1, state that they felt uncomfortable and suffering coldness due to very low temperature of centralizing air-conditioning especially during non-peak hours. Therefore, five parameters pointed to be measured based on the complaints from staff due to IAQ problems especially from Heating, Ventilating, and Air Conditioning (HVAC) system. By using 4 in 1 Meter Kit, three environmental parameters recorded such as air temperature (t), relative humidity (RH) and air velocity (AV) and the average result are 22.5°C, 57.7% and 0.02 m/s, respectively. Meanwhile, two chemical parameters recorded are carbon dioxide (CO2) with 875ppm and formaldehyde (CH2O) is 0.11ppm were measured using IAQ Calc model 7545 and Formaldehyde Meter Z-300 devices value within the standard. Thus, the result shows that the HVAC system affects the IAQ parameters in ACCXYZ building through a major impact on the temperature due to patient and staff environment and also to the operation of the sensitive machine in the building.