Evaluation of a Low-Cost Air Renewal System for Indoor Air Quality Control in a Climate Chamber

There is a growing concern about Indoor Environmental Quality (IEQ) in buildings as humans are spending longer in indoor environments, whether this is associated or not with climate change and vulnerability to extreme weather events. In the wake of the COVID pandemic, the need for indoor air quality control is likely to increase, the result of many adaptations in home environments to switch to remote work. In hot countries in the Global South, one of the alternatives is split A/C units with limited air renewal. While, odorless and colorless CO2, commonly generated by occupants through respiration, is among the relevant indoor air pollutants. The purpose of this study is to evaluate a low-cost, responsive air-renewal system in a climate chamber equipped with a standard split A/C unit. The results show the system's feasibility in curbing IAQ concerns and also highlight the risk of negative impacts on indoor thermal conditions and on energy consumption on using A/C. © 2023, The Author(s), under exclusive license to Springer Nature Switzerland AG.

REVIEW AND ANALYSIS OF EXISTING METHODS TO ASSESS THE INDOOR ENVIRONMENTAL QUALITY (IEQ) FOR OFFICE BUILDINGS

Population in developed countries spend most of their time indoors, whether in their homes, workplaces, stores or leisure areas. Due to the COVID-19 pandemic, this situation worsened and now, more than ever, the importance of a high Indoor Environmental Quality (IEQ) is highlighted. The IEQ is very important in building performance since it is directly related to its occupants' comfort, health, wellbeing, and productivity and the Sick Building Syndrome (SBS) concept. Therefore, it is essential to develop tools to support designers' decision-making in the materialization of indoor environments with higher quality. From the state-of-art analysis, it is possible to conclude that the methods to assess the overall building performance already consider the IEQ. Still, most use an approach that does not cover all relevant indicators. In this context, this paper presents the first milestone of a research work that aims to develop a new method to rate the overall IEQ of office buildings in Portugal. The main objective of the present study is to propose a list of IEQ indicators for office buildings, adapted to the Portuguese context, based on the analysis of existing rating methods for buildings and the recommendations of national and international standards. © 2022 The Author(s). Licensed under a CC-BY 4.0 licence.

Barriers to incorporation of indoor environmental quality (IEQ) principles into building designs

PurposeThis research presents a comprehensive review of the literature on the barriers to incorporating indoor environmental quality (IEQ) principles into building designs. The aim was to identify these barriers in the literature and subsume them under broad categories for the development of a framework showing the interrelationships among the barriers.Design/methodology/approachThe research design used a systematic desktop review which comprised of three levels of screening. The first level allowed for a broad selection of papers;the second level of screening was done to limit the results to papers within the construction industry, and the third level of screening limited the documents strictly to the publication period of 2000–2021.FindingsTwenty-four (24) barriers were identified in the literature, including lack of integrated design teams, which ranked the highest in appearance, high initial costs, poor market for IEQ buildings and higher design charges among others. The identified barriers were classified into six (6) categories namely capacity barriers, economic barriers, process-related barriers, cultural barriers, client-related barriers and steering barriers.Practical implicationsThe findings of this study would enable practitioners and policymakers to better understand what is preventing the widespread adoption of IEQ designs in the built environment and devise actionable strategies to overcome them. It adds to the body of knowledge on IEQ research by categorizing the various barriers that prevent the delivery of IEQ projects.Social implicationsThe developed barriers in this research can serve as a useful checklist to future researchers who may want to validate the barriers to IEQ designs in empirical studies and in different settings.Originality/valueThe interconnectivity revealed by the web-like framework allows for an appreciation of the various barriers of IEQ adoption which would help in expanding the current knowledge on IEQ beyond the narrow scope of isolated barriers. The fact that the papers selected in this study are not limited geographically, underscores the wide applicability of the findings in the global construction industry.

Interrelationship between strategic factors, technology and organizational learning: a systematic literature review

Purpose - The present shift and change in the human lifestyle across the world are undeniable. Currently, individuals spend a substantial amount of time indoors due to the global COVID-19 pandemic that strikes the entire world. This change in human lifestyle has devastating effects on human health and productivity. As a result, the influence of indoor environmental quality (IEQ) on the health and productivity of building users becomes a critical field of research that requires immediate attention. As a result, the purpose of this study is to review the state-of-the-art literature by establishing a connection between the factors that influence health and productivity in any given indoor environment.Design/methodology/approach - The methodology involves a thorough review of selected published journals from 1983 to 2021, and the result was analysed through content analysis. The search included journal articles, books and conference proceedings on the critical factors influencing IEQ and their impact on building occupants, which was sourced from different databases such as ScienceDirect, Taylor, GoogleScholar and Web of Science.Findings - The findings from the 90 selected articles revealed four critical factors influencing the quality of the indoor environment and are categorised into;indoor air quality, indoor thermal comfort, visual comfort and acoustic comfort. The findings suggested that when developing a system for controlling the quality of the indoor environment, the indoor air quality, indoor thermal comfort, visual comfort and acoustic comfort should be taken into account.Originality/value - The indoor environment deeply impacts the health of individuals in their living and work environments. Industry must have a moral responsibility to provide health facilities in which people and workers feel satisfies and give conditions for prosperity. Addressing these essential aspects will not only help the decision-making process of construction professionals but also encourages innovative construction techniques that will enhance the satisfaction, wellness and performance of building occupants.

Comparison of indoor air quality and thermal comfort standards and variations in exceedance for school buildings

Addressing indoor air quality (IAQ) and thermal comfort issues in school buildings is challenging but relevant. Firstly, their primary occupants are more vulnerable than adults. Secondly, school buildings are often inadequate being too old or designed to prioritise energy-efficiency targets. Thirdly, occupants have often little control over the indoor environmental quality (IEQ). Lastly, the SARS-CoV-2 pandemic highlighted the complexity and vulnerability of existing decision-making processes in relation to making timely and well-informed decisions about IEQ threats. Standards and guidelines vary over time and among similar countries despite targeting similar occupants, evaluate IAQ and thermal comfort independently, and do not include any specific adaptations to children. Thus, the aim of this research is to compare different available standards to evaluate IAQ and thermal comfort in school buildings. By analysing with different standards (EN16798, BB101, and ASHRAE 55 and 62.1) the data collected in schools in northern Italy, this research evaluated the consequences of different limits and approaches, and proposed improvements. The conclusions are that (i) thresholds and methods inconsistency within the same standard should be avoided;(ii) upper- and lower-bounded operative temperature scales are the most appropriate means to design and verify thermal comfort in classrooms;(iii) IAQ metrics that give an upper limit per a certain amount of consecutive time might prevent the build-up of indoor pollutants, even with high emissions from the building fabric;(iv) no standard proposes a combined IAQ and thermal comfort analysis which could enable more informed trade-off decisions considering IAQ, thermal comfort, and energy targets. © 2023 The Authors

Offerings and challenges of demand response ventilation under covid-19 scenarios

Owning to the outbreak of COVID-19, individuals have to spend more time indoor. It is therefore essential to prepare for a long-term healthy indoor working environment in the transition of post COVID-19 pandemic. However, there is no relevant research so far in investigating such crisis impacts around indoor environmental quality and economic-health issues while home offices are expected becoming common practice soon. Therefore, a case of single-family house in Sweden is specially investigated using IDA ICE. By comparing four predominant ventilation approaches, three operational schedules are proposed, covering different confinement for occupants. Main results show that the demand response ventilation (DRV) generally should sacrifice in remarkable performance in energy saving, and emission reduction to better confront with more challenges in indoor air quality, occupied thermal dissatisfaction fraction and air stagnation under the challenge of COVID-19 pandemic scenario. Altered ventilation strategy should be customized from increased outdoor air supply, various demand-control signal, displacement method towards a heathier homeworking environment. © International Building Performance Simulation Association, 2022

Airport terminal passenger forecast under the impact of COVID-19 outbreaks: A case study from China

Passengers significantly affect airport terminal energy consumption and indoor environmental quality. Accurate passenger forecasting provides important insights for airport terminals to optimize their operation and management. However, the COVID-19 pandemic has greatly increased the uncertainty in airport passenger since 2020. There are insufficient studies to investigate which pandemic-related variables should be considered in forecasting airport passenger trends under the impact of COVID-19 outbreaks. In this study, the interrelationship between COVID-19 pandemic trends and passenger traffic at a major airport terminal in China was analyzed on a day-by-day basis. During COVID-19 outbreaks, three stages of passenger change were identified and characterized, i.e., the decline stage, the stabilization stage, and the recovery stage. A typical "sudden drop and slow recovery” pattern of passenger traffic was identified. A LightGBM model including pandemic variables was developed to forecast short-term daily passenger traffic at the airport terminal. The SHapley Additive exPlanations (SHAP) values was used to quantify the contribution of input pandemic variables. Results indicated the inclusion of pandemic variables reduced the model error by 27.7% compared to a baseline model. The cumulative numbers of COVID-19 cases in previous weeks were found to be stronger predictors of future passenger traffic than daily COVID-19 cases in the most recent week. In addition, the impact of pandemic control policies and passengers' travel behavior was discussed. Our empirical findings provide important implications for airport terminal operations in response to the on-going COVID-19 pandemic. © 2022

Natural ventilation as a healthy habit during the first wave of the COVID-19 pandemic: An analysis of the frequency of window opening in Spanish homes

Since SARS-CoV-2 spread worldwide in early 2020, many countries established lockdowns for protection. With a main transmission by aerosols, ventilation was promoted. This article analyses natural ventilation of Spanish housing during the spring 2020. An online questionnaire was launched, obtaining for this study 1502 responses. The comparative window opening before and during confinement, and households, dwellings and home activity variables, were analysed. The binary logistic regression model before pandemic indicated that ventilating properly related to: a worse perceived IAQ (OR = 1.56);thermal adaptation measures, especially those that prefer to open/close windows (OR = 1.45);not having heating system (OR = 1.15);and using power to heat water (OR = 1.60). For the confinement period, the model highlighted: being an employee (OR = 1.88);using heavy clothing in the home (OR = 2.36);and again, open/close windows for adaptation (OR = 2.24). According to specific tasks in quarantine, frequent ventilation was boosted by: an increasing use of oven (OR = 14.81);and alteration of work-habits (OR = 2.70), sport-habits (OR = 1.79), and outdoor-activities (OR = 1.60). Thus, an adequate natural ventilation pattern during the quarantine was linked to low environmental comfort in general, by virtue of indoor air quality. This is corroborated by less acoustic-thermal insulation, worse indicators of heating use, and the adaptive response to opening/closing windows when external temperature changed. © 2022 The Authors

Synthesis of critical factors influencing indoor environmental quality and their impacts on building occupants health and productivity

Purpose: The present shift and change in the human lifestyle across the world are undeniable. Currently, individuals spend a substantial amount of time indoors due to the global COVID-19 pandemic that strikes the entire world. This change in human lifestyle has devastating effects on human health and productivity. As a result, the influence of indoor environmental quality (IEQ) on the health and productivity of building users becomes a critical field of research that requires immediate attention. As a result, the purpose of this study is to review the state-of-the-art literature by establishing a connection between the factors that influence health and productivity in any given indoor environment. Design/methodology/approach: The methodology involves a thorough review of selected published journals from 1983 to 2021, and the result was analysed through content analysis. The search included journal articles, books and conference proceedings on the critical factors influencing IEQ and their impact on building occupants, which was sourced from different databases such as ScienceDirect, Taylor, GoogleScholar and Web of Science. Findings: The findings from the 90 selected articles revealed four critical factors influencing the quality of the indoor environment and are categorised into;indoor air quality, indoor thermal comfort, visual comfort and acoustic comfort. The findings suggested that when developing a system for controlling the quality of the indoor environment, the indoor air quality, indoor thermal comfort, visual comfort and acoustic comfort should be taken into account. Originality/value: The indoor environment deeply impacts the health of individuals in their living and work environments. Industry must have a moral responsibility to provide health facilities in which people and workers feel satisfies and give conditions for prosperity. Addressing these essential aspects will not only help the decision-making process of construction professionals but also encourages innovative construction techniques that will enhance the satisfaction, wellness and performance of building occupants. © 2023, Modupe Cecilia Mewomo, James Olaonipekun Toyin, Comfort Olubukola Iyiola and Olusola Raphael Aluko.

Protective Factors Contributing to Academic Resilience in College Students During COVID-19

We sought to examine the potential environmental protective factors contributing to academic resilience among college students during emergency distance education. Data were collected from a sample of undergraduate students (n = 195) representing various majors and academic classifications. Our study results revealed that students perceived their motivation and comprehension of course material during emergency distance education as significantly lower than those before emergency distance education. Moreover, over 26% of the participants reported a decreased GPA during this period. However, a positive physical learning environment and student-perceived teacher academic support benefited students' academic performance. Interestingly, the physical learning environment positively predicted teacher academic support, beta=.31, t(193) = 4.32, p < .001. The physical learning environment also explained a significant proportion of variance in teacher academic support scores, R-2 = .08, F(1, 193) = 16.25, p < .001, suggesting student perceptions of teacher support partially depends on their physical learning environment. Finally, students that had a higher classification were more likely to report an increased GPA;seniors were better at coping with the negative effects of emergency distance education than juniors and sophomores.

Review of an intelligent indoor environment monitoring and management system for COVID-19 risk mitigation.

The coronavirus disease (COVID-19) outbreak has turned the world upside down bringing about a massive impact on society due to enforced measures such as the curtailment of personal travel and limitations on economic activities. The global pandemic resulted in numerous people spending their time at home, working, and learning from home hence exposing them to air contaminants of outdoor and indoor origins. COVID-19 is caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), which spreads by airborne transmission. The viruses found indoors are linked to the building's ventilation system quality. The ventilation flow in an indoor environment controls the movement and advection of any aerosols, pollutants, and Carbon Dioxide (CO2) created by indoor sources/occupants; the quantity of CO2 can be measured by sensors. Indoor CO2 monitoring is a technique used to track a person's COVID-19 risk, but high or low CO2 levels do not necessarily mean that the COVID-19 virus is present in the air. CO2 monitors, in short, can help inform an individual whether they are breathing in clean air. In terms of COVID-19 risk mitigation strategies, intelligent indoor monitoring systems use various sensors that are available in the marketplace. This work presents a review of scientific articles that influence intelligent monitoring development and indoor environmental quality management system. The paper underlines that the non-dispersive infrared (NDIR) sensor and ESP8266 microcontroller support the development of low-cost indoor air monitoring at learning facilities.

Winter in Europe 2022-2023 - Concerns About The Effects of The Energy Crisis On Indoor Environmental Quality and Public Health

The fall of 2022 finds the old continent in a highly problematic economic and political context. The effects of the covid pandemic have not yet been overcome, but new problems generated by an armed conflict in Europe and a harsh climate context have been added. European political leaders are stuck on topics related to saving resources and the economic survival of their own countries. The economic and social measures suggested by the political class under the pressure of the approaching winter risk generate effects on the population's health with more devastating long-term results than the covid pandemic. Reducing electricity consumption at any cost, reducing water consumption, and adjusting the thermal comfort parameters in dwellings on a large scale can affect the population's health and lead to subsequent costs that are difficult to estimate. This paper tries to analyze this context and identify a method for evaluating the effects on indoor environmental quality. © 2022 IEEE.

What Is the Temperature Acceptance in Home-Office Households in the Winter?

Remote work can have many benefits when set up properly. Nevertheless, the preferences of home workers' comfort havenot been profoundly studied yet. Therefore, this study aims to understand their accepted Indoor Environmental Quality values in winter based on self-reported comfort. In this regard, 26 households in Catalonia's Mediterranean region were monitored and surveyed for separated periods of 15 days during from 22 November 2021 to 6 March 2022. Measurements including temperature, temperature, CO2 and Relative Humidity levels were data logged in their most used workspace. Results show that most people work between 18 °C to 20 °C and find those temperatures acceptable. Common spaces used as homeoffices are on average 0.8 °C warmer and there are 470 ppm lower CO2 concentrations. Families with children or teenagers and especially women tend to have a warmer mean operative temperature. The comparison between theoretical thermal comfort models (Fanger and Adaptive) to direct vote perception from a sample of spaces and conditions shows low correlation with real perception having the Adaptive model a better prediction of votes. In general, people report feeling more comfortable at the office, although a high number of participants feel indifferent or reckon that depends on other factors.

A review on indoor environmental quality in sports facilities: Indoor air quality and ventilation during a pandemic

Because of COVID-19, the indoor environmental quality (IEQ) in sports facilities has been a concern to environmental health practitioners. To develop an overall understanding of the available guidelines and standards and studies performed on IEQ in sports facilities, an extensive literature study was conducted, with the aim of identifying: (1) indicators that are being used to assess IEQ in different sports facilities;(2) indicators that are potentially interesting to be used to assess indoor air, in particular;(3) gaps in knowledge to determine whether sports facilities are safe, healthy and comfortable for people to stay and perform their activities. The outcome indicates that most current standards and previous investigations on IEQ in sports facilities mainly focused on dose-related indicators (such as ventilation rate), while building-related indicators (such as ventilation regime) and occupant-related indicators (such as IEQ preferences) were rarely considered. Little attention is given to the fact that ventilation systems may play an important role in the air quality of the location, and few investigations have been performed on the transmission of SARS-CoV-2. This study recommends more research into both occupant and building-related indicators as well as cross-modal effects between various IEQ factors for developing future standards on sports facilities.

Natural ventilation as a healthy habit during the first wave of the COVID-19 pandemic: An analysis of the frequency of window opening in Spanish homes

Since SARS-CoV-2 spread worldwide in early 2020, many countries established lockdowns for protection. With a main transmission by aerosols, ventilation was promoted. This article analyses natural ventilation of Spanish housing during the spring 2020. An online questionnaire was launched, obtaining for this study 1502 responses. The comparative window opening before and during confinement and households, dwellings and home activity variables, were analysed. The binary logistic regression model before pandemic, indicated that ventilating properly related to: a worse perceived IAQ (OR = 1.56);thermal adaptation measures, especially those that prefer to open/close windows (OR = 1.45);not having heating system (OR = 1.15);and using power to heat water (OR = 1.60). For the confinement period, the model highlighted: being an employee (OR = 1.88);using heavy clothing in the home (OR = 2.36);and again, open/close windows for adaptation (OR = 2.24). According to specific tasks in quarantine, frequent ventilation was boosted by: an increasing use of oven (OR = 14.81);and alteration of work-habits (OR = 2.70), sport-habits (OR = 1.79), and outdoor-activities (OR = 1.60). Thus, an adequate natural ventilation pattern during the quarantine linked to low environmental comfort in general, by virtue of indoor air quality. This is corroborated by less acoustic-thermal insulation, worse indicators of heating use, and the adaptive response to opening/closing windows when external temperature changed.

Can Homes Affect Well-Being? A Scoping Review among Housing Conditions, Indoor Environmental Quality, and Mental Health Outcomes.

The purpose of the scoping review is to explore the relationship between housing conditions, indoor environmental quality (IEQ), and mental health implications on human well-being. In fact, time spent at home increased due to the recent COVID-19 lockdown period, and social-sanitary emergencies are expected to grow due to the urbanization phenomenon. Thus, the role of the physical environment in which we live, study, and work, has become of crucial importance, as the literature has recently highlighted. This scoping review, conducted on the electronic database Scopus, led to the identification of 366 articles. This, after the screening processes based on the inclusion criteria, led to the final inclusion of 31 papers related specifically to the OECD area. The review allowed the identification of five housing conditions [house type, age, and floor level; housing qualities; household composition; neighborhood; green spaces] that, by influencing the IEQ parameters, had impacts on the mental health outcomes addressed. By synthesizing the contributions of the review, a list of design recommendations has been provided. These will serve as a basis for future researchers, from which to develop measures to reduce inequalities in housing by making them healthier, more resilient, and salutogenic.

Monitoring and Assessment of Indoor Environmental Conditions in Educational Building Using Building Information Modelling Methodology.

Managing indoor environmental quality (IEQ) is a challenge in educational buildings in the wake of the COVID-19 pandemic. Adequate indoor air quality is essential to ensure that indoor spaces are safe for students and teachers. In fact, poor IEQ can affect academic performance and student comfort. This study proposes a framework for integrating occupants' feedback into the building information modelling (BIM) methodology to assess indoor environmental conditions (thermal, acoustic and lighting) and the individual airborne virus transmission risk during teaching activities. The information contained in the parametric 3D BIM model and the algorithmic environment of Dynamo were used to develop the framework. The IEQ evaluation is based on sensor monitoring and a daily schedule, so the results show real problems of occupants' dissatisfaction. The output of the framework shows in which range the indoor environmental variables were (optimal, acceptable and unacceptable) and the probability of infection during each lecture class (whether or not 1% is exceeded). A case study was proposed to illustrate its application and validate it. The outcomes provide key information to support the decision-making process for managing IEQ and controlling individual airborne virus transmission risks. Long-term application could provide data that support the management of ventilation strategies and protocol redesign.

Use of work-space at home under COVID-19 conditions in the UAE

Purpose The study assesses user satisfaction of workspaces modified at home in response to the COVID-19 pandemic, thereby analyzing the flexibility of modern homes in the twenty-first century in the United Arab Emirates. Design/methodology/approach Data was collected using a structured online survey from 113 participants about their home office created to accommodate working/studying from home. Analysis of survey revealed the importance of type of residence in affecting satisfaction of functionality and well-being. Findings The collected demographic variables played a crucial role in affecting satisfaction with various elements, from indoor air quality of the working space to the amount of natural light received by the space. Finally, participants who felt the need to add color and change furniture layout, experienced feelings of productivity, commitment and motivation by working from home. The same participants decided to keep the amended changes to their living spaces, even after they return to working from their offices. The study concludes by presenting implications of this experience on future home designs;thereby offering suggestions of authorities, and designers to produce more flexible and resilient houses. Research limitations/implications A relatively small sample with limited professions was considered. Further research recommendations include increasing the sample size to target more categories of the residents of the UAE. Future research can expand the criteria used to evaluate satisfaction and include noise levels as well as accessibility. Practical implications The study offers suggestions to authorities and designers to produce more flexible and resilient homes, taking demographics into consideration. Roof gardens, shading devices and privacy needs are crucial elements for the future home. Originality/value The research provides enough information to inform designers about the future of space interiors, how well they are configured, serviced and how adaptable they are, in order to enhance user satisfaction.

Dwelling in times of COVID-19: An analysis on habitability and environmental factors of Spanish housing

In the wake of the SARS-CoV-2 pandemic, promoted by the World Health Organization (WHO), governments urged people to stay at home. For this reason, practically all human activity took place inside the houses. The research question established if housing quality responded to people's needs in the context of confinement. Specifically, the purpose was to taxonomize the dwelling stock occupied by confined households during the first COVID-19 wave in Spain, as well as to deepen in features and subjective perceptions on Indoor Environmental Quality (IEQ). As an exploratory study, an online questionnaire was disseminated in the Spring of 2020, obtaining 1,673 valid responses. A descriptive statistical analysis included sociodemographic, territorial and housing variables, related to indoor environmental quality, the availability of outdoor spaces, and the prospects for changes in. Also, a logistic regression stablished multivariate relations for the dependent variable “general dwelling satisfaction”. The results associated urban habitat, tenancy regime, higher incomes, and fewer cohabitants, with worse perceived IEQ, and lack of own outdoor space. Same variables showed relations with people's desire for domestic changes. In conclusion, it is remarkable the determining role of housing design for dwellers’ satisfaction, especially in uncertain times like COVID-19 pandemic. This not only conditioned the different ways of inhabiting and occupying dwellings, but also the people's capacity to face lockdown. The built environment, the habitat, and households’ circumstances also influenced. The latter did on people's perception of their experience, and how they lived and expressed it. Additionally, resilient building design and renovation opportunities were identified. © 2022

Influence of the Heating System on the Indoor Environmental Quality—Case Study

This aim of this paper is to explore the specific indoor environmental quality factors under different heating conditions in a meeting room of an administrate building located in Kosice. In terms of thermal comfort, a system with radiant ceiling heating provides more favorable results. Low relative humidity was recorded for both heating systems, which could be due to insufficient air conditioning settings. The results of measuring CO2 concentrations were almost identical for both systems and did not exceed the recommended limit value of 1000 ppm. The increase in CO2 concentrations was mainly related to the presence of employees in the monitored room. On none of the monitoring days, whether in the case of a mechanical heating system or a radiant ceiling heating system, the average 24 h concentration of PM10 did not exceed the legally permissible limit of 50 µg/m3. The presence of selected volatile organic compounds in the room has not been demonstrated due to effective ventilation by air conditioning. The results of the evaluation were comparable and smaller fluctuations in values can be attributed to other factors, such as the presence of persons in the monitoring room or the overall heating as well as ventilation and air conditioning (HVAC) systems.