Indoor Environmental Quality Assessment Research Articles

Assessment of Indoor Environmental Quality of Mymensingh Medical College Hospital

Assessment of Indoor Environmental Quality of Mymensingh Medical College Hospital

Framing holistic indoor environment: Definitions of comfort, health and well-being

In research and assessment of indoor environmental quality (IEQ), the terms ‘Comfort’, ‘Health’ and ‘Well-being’ are often used interchangeably without a clear definition of terms or effects on conditions for occupants. This calls for a systematic restructuring of the ontological approach to IEQ and, based on a meta-analysis of recent IEQ literature, the authors suggest three substantial contributions: 1) A framework consisting of comfort, health and well-being as three equal branches of IEQ to increase focus on previously neglected aspects and make inter-domain relations more transparent. 2) The identification of key IEQ trends and by extension suggestions for formal definitions of three main domains as part of a multidisciplinary conceptual framework for working holistically with IEQ. 3) The introduction of positive stimuli to IEQ assessment as opposed to the predominance of focus on the absence of negative parameters of current practice. Through including this positive stimuli dimension, the field of IEQ shifts from ‘not bad’ to ‘truly good’, encouraging the design of enriched environments to further positive experiences improving occupant well-being.

An Assessment of Indoor Environmental Quality in School Buildings in the State of Kuwait

In this study, indoor quality and environmental comfort were investigated in secondary school buildings located in the State of Kuwait. Comfort variables such as temperature and relative humidity (thermal comfort), noise (acoustic comfort), illumination (visual comfort), as well as allocated classroom floor area per student (spatial comfort) were measured. Data was collected over a 7-month period on a spot basis during school hours in student-occupied classrooms at 46 selected schools. The measured data was then compared to international guidelines and standards related to indoor environment quality. The data for noise and allocated space were shown to be in the comfort ranges in all the schools. However, 11% of the schools are not adequately illuminated, 33% had temperatures not within the recommended limits, and 22% of the schools had humidity levels either higher or lower than the recommended levels. Also, 9% of the schools had low illumination readings.In addition, during the data monitoring, a survey was conducted by which the student occupants completed a questionnaire so that subjective and objective evaluations could be compared. The findings of the questionnaire displayed significant correlations between the measured data and some ailments and other complaints experienced by the students.Ultimately, the results found in this research will provide a baseline for comparison with future indoor environment quality assessments in buildings. Furthermore, recommendations are suggested in order to improve the environmental quality problems encountered in some of the schools, which may be beneficial for policymakers, facilities managers, and design engineers.

Building and indoor environmental quality assessment of Nigerian primary schools: A pilot study

A total of 15 classrooms went through on-site assessments/inspections, including measurements of temperature (T), and concentrations of carbon monoxide (CO) and carbon dioxide (CO2 ). In addition, the level of surface biocontamination/cleaning effectiveness was assessed by measuring adenosine triphosphate (ATP) levels on students' desks. Based on the data, the quality of facilities in the buildings was low. Classroom occupancy exceeded ASHRAE 50 person/100m2 standard in all cases indicating overcrowding. However, concentrations of CO2 remained below 1000ppm in most classrooms. On the other hand, indoor T was above the recommended levels for thermal comfort in all classrooms. Maximum indoor CO was 6ppm. Median ATP concentrations on the desk tops were moderately high in all schools. The use of open incinerators and power generator sets near classrooms, which was suspected to be the main source of CO, should be discouraged. Improved hygiene could be achieved by providing the students access to functioning bathroom facilities and cafeteria, and by effective cleaning of high contact surfaces such as desks. Although ventilation seems adequate based on CO2 concentrations, thermal comfort was not attained especially in the afternoon during extreme sunlight. Therefore, installing passive and/or mechanical cooling systems should be considered in this regard.

Development of an Indoor Environmental Quality Assessment Tool for the Rating of Offices in Real Working Conditions

The Indoor Environmental Quality (IEQ) refers to the quality of indoor spaces in relation to the health and well-being of users. IEQ is a holistic concept considering various components of the overall indoor comfort: thermo-hygrometric, lighting, air quality and acoustics. Each component is described through specific performance indicators and benchmarks. The quality of the built environment is assessed at different stages from design to operational phase. The scientific literature reports several case studies related to the assessment of the individual components of the IEQ Tools aimed at the evaluation of the overall IEQ. The paper proposes an assessment tool based on the SB Method (Sustainable Building Method) and the Multi Criteria Analysis for the evaluation of IEQ during the operational phase of a building. Each component of IEQ is analysed through objective indicators and calculation methods. The tool provides two main outcomes: a global score expressing the overall performance of the building from the IEQ perspective; quantitative evaluations of all indoor comfort components through monitoring and measurement of the environmental variables. The above contributes to select intervention areas to optimize indoor design and to identify technologies aimed at ensuring the best IEQ levels for users at the operational stage. The system was applied to an open-plan working space of an office building. Monitoring activities and measurements are carried out to detect the indoor and outdoor variables affecting the IEQ. All aspects of IEQ were analysed and quantified so to evaluate the overall performance of the building and provide data to improve the working conditions.

Assessment of Indoor Environmental Quality for Retrofitting Classrooms with An Egg-Crate Shading Device in A Hot Climate

In the Mediterranean climate, a large number of educational buildings suffer from discomfort due mostly to energy-deficient thermal envelopes and a lack of cooling systems. Impending climate change is expected to worsen overheating in classrooms, especially during heatwave periods. Therefore, the protection of window openings to reduce incident solar radiation while maintaining adequate indoor environmental quality must be considered a necessary key focus. The main objective of this research is to assess the influence of an egg-crate shading device on the indoor environmental quality of a classroom in Southern Spain. To do so, two classrooms—with and without this shading device—were simultaneously monitored over a whole year. The implementation of an egg-crate shading device allowed for a significant reduction of the incident solar radiation, both in summer and mid-season (around 45–50%), which objectively slightly conditioned indoor operative temperatures. Given the noticeable influence of the user patterns observed, indoor illuminance was also improved, as the rolling shutters tended to be opened at higher aperture levels.

Utilisation of building information modelling for indoor environmental quality assessment – A review

The indoor environmental quality (IEQ) is considered as a social aspect of sustainability that concerns on health, safety and well-being of building occupants. The satisfaction of occupants in the buildings is affected by acoustic, thermal, lighting and ventilation and has been corresponding to the self-estimated workers job performance in the workspace. The poor indoor environmental quality in building has resulted to health problems such as asthma and cancers and this having an effect in frequency of absenteeism and intention to quite job. Therefore, occupant satisfaction is an important factor in the design, operation, and management of buildings. This study reviews the extent to which relevant literature on IEQ has been carried out and the utilisation of Building Information Modelling (BIM) for the IEQ assessment. Reviewed works shows that many works have been carried out on indoor environmental quality of buildings and other aspect of sustainability such as environmental and economic sustainability. However, despite an increased interest in GreenBIM, it is surprising that little empirical research has been conducted on the topic. Most of the studies are directed towards the environmental benefits of sustainability such as energy consumption, carbon dioxide emission, and waste reduction. This study aims to identify areas that are yet to be considered and provides information on interventions that could be used to improve the health and wellbeing of occupants of the building is a compliment to previous studies that are on the other components of sustainability.

PERFORMANCE OF A GREEN BUILDING'S INDOOR ENVIRONMENTAL QUALITY ON BUILDING OCCUPANTS IN SOUTH AFRICA

Indoor environmental quality (IEQ) is important to the health, comfort, and well-being of building occupants. Unsatisfactory IEQ is associated with a number of phenomena, most notably, sick building syndrome (SBS), building-related illnesses (BRIs), and multiple chemical sensitivity (MCS), which have major negative effects on productivity. However, green building investors (owners) are not only concerned about reducing the negative impact of their buildings on the environment, but also about the potentially negative impact green buildings can have on their employees' productivity. This research sets out to address, through a questionnaire survey in South Africa, what constitutes the determinants of green building occupants' satisfaction with the IEQ elements of a green building and the health implications of a building's IEQ on the building occupants. Data analysis (involving a one-sample t-test) reveals some interesting findings in regard to what constitutes the determinants of green building occupants' satisfaction with the IEQ elements and the health implications of the IEQ elements of a five-star green rated building in South Africa. Findings from the survey revealed that the occupants of the building were not satisfied with the green building's IEQ, most especially the ineffectiveness of blocking natural and artificial lighting. Also, it was revealed that the IEQ with particular reference to the noise level and ventilation of the space has some serious health implications for the building occupants. The occupants' evaluation revealed that the major health issues from which they suffer include fatigue, headache, common cold, coughing, and influenza, and these affect their productivity and performance. Since building occupants are a rich source of information about IEQ assessment and its effect on productivity, the study can be used to assess the performance of green buildings, identify areas needing improvement, and provide useful feedback to designers and operators about specific aspects of green building design features and operating strategies that need improvement. This study adds to the body of knowledge on green buildings' IEQ performance.

Post-Occupancy Evaluation and IEQ Measurements from 64 Office Buildings: Critical Factors and Thresholds for User Satisfaction on Thermal Quality

The indoor environmental quality (IEQ) of buildings can have a strong influence on occupants’ comfort, productivity, and health. Post-occupancy evaluation (POE) is necessary in assessing the IEQ of the built environment, and it typically relies on the subjective surveys of thermal quality, air quality, visual quality, and acoustic quality. In this research, we expanded POE to include both objective IEQ measurements and the technical attributes of building systems (TABS) that may affect indoor environment and user satisfaction. The suite of three tools, including user satisfaction survey, workstation IEQ measurements, and TABS in the National Environmental Assessment Toolkit (NEAT) has been deployed in 1601 workstations in 64 office buildings, generating a rich database for statistical evaluation of possible correlations between the physical attributes of workstations, environmental conditions, and user satisfaction. Multivariate regression and multiple correlation coefficient statistical analysis revealed the relationship between measured and perceived IEQ indices, interdependencies between IEQ indices, and other satisfaction variables of significance. The results showed that overall, 55% of occupants responded as “satisfied” or “neutral”, and 45% reported being “dissatisfied” in their thermal quality. Given the dataset, air temperature in work area, size of thermal zone, window quality, level of temperature control, and radiant temperature asymmetry with façade are the critical factors for thermal quality satisfaction in the field. As a result, the outcome of this research contributes to identifying correlations between occupant satisfaction, measured data, and technical attributes of building systems. The presented integrated IEQ assessment method can further afford robust predictions of building performance against metrics and guidelines for IEQ standards to capture revised IEQ thresholds that impact building occupants’ satisfaction.

Development of a non-domestic building refurbishment scheme for Malaysia: A Delphi approach

Building refurbishment is a key in promoting environmentally sustainable development due to its potential for reducing greenhouse gas emissions and energy consumption associated with existing buildings. The general metrics for assessing the impacts of refurbishment have not been established for existing buildings in most of the countries. In Malaysia, there is currently no single environmental assessment scheme for building refurbishment. The existing environmental assessment schemes are not sufficiently robust, as they do not include factors such as quality of services and economics. It is essential to have a customised suite of sustainability schemes specifically designed for the Malaysian context to facilitate best practice for non-domestic refurbishment assessment. A comprehensive Delphi process was developed to assist in the identification of suitable assessment schemes for use in non-domestic buildings. Three successive rounds of surveys were conducted with ten Delphi experts with expertise in sustainability and green assessment. The study revealed that energy related factors such as air-conditioning were ranked as the most important assessment theme for refurbishment, followed by indoor environmental quality and water assessment. The findings of this research will be used to develop a weighting system by using the analytic hierarchy process in the next research stage, leading to a complete refurbishment environmental assessment scheme.

Indoor Environmental Quality Assessment of Historic Buildings in the State Park: A Case Study in Michigan

Michigan State University and the Michigan Department of Natural Resources established a partnership for sustainable park planning in October 2011. The purpose of the partnership was to enable students in the design fields to work on real-world projects and provide practical solutions. One of the notable projects was to assess old historic buildings in one state park and propose renovation plan to improve its indoor environmental quality and energy efficiency. The buildings in the park functioned as the traveler’s destination in the 1920s and still preserve original interior and exterior features. 
 
 The team of undergraduates and faculty in interior design visited the park and assessed the interior and exterior conditions of two of its buildings. They used an assessment tool which was designed on a basis of the elements in the indoor environmental quality category (IEQ) of the US Green Building Council’s LEED. Results revealed that the indoor environmental conditions of the buildings should be improved. The energy efficiency of the buildings was low. Based on this assessment, this study offered practical suggestions for improving the building’s indoor environmental quality. This study also proposed an assessment tool for the historic buildings in the state parks in Michigan to assess current indoor environmental quality of those buildings.

Indoor Environmental Quality Assessment Model IEQ Developed in ITB. Part 2. Model Reliability Analysis

Indoor Environmental Quality Assessment Model IEQ Developed in ITB. Part 2. Model Reliability Analysis

Indoor Environmental Quality Assessment Model IEQ Developed in ITB. Part 1. Choice of the Indoor Environmental Quality Sub-Component Models

Indoor Environmental Quality Assessment Model IEQ Developed in ITB. Part 1. Choice of the Indoor Environmental Quality Sub-Component Models

An Indoor Environmental Quality (IEQ) assessment of a partially-retrofitted university building

Achieving standards-based Indoor Environmental Quality (IEQ) in existing buildings is growing steadily due to the strong demand for deep retrofits in Europe. Existing non-domestic buildings pose challenges mainly due to occupancy patterns, lack of personal control over comfort and outdated building structures. Renovations of many post-war non-domestic buildings (>35 years old) have faced technical and financial challenges. Consequently, these buildings are often only partially retrofitted, which are often ad-hoc in nature. This paper describes the evaluation process of indoor environmental conditions in a partially-retrofitted university building in Galway (Ireland) originally built during the 1970s and partially retrofit in 2005. The research assesses criteria outlined in EN 15251 and draws on methods from ASHRAE 55 and CBE IEQ survey. Occupant surveys complemented by physical measurements were used to assess the compliance of IEQ parameters for thermal, visual and acoustic comfort and indoor air quality. The relationship between the performance of the building envelope and occupant comfort is described across retrofitted and non-retrofitted zones of the building. The results suggest that ad-hoc retrofitting of the façade did not make any significant difference to IEQ and occupants continued to adapt personally to the existing conditions. Their preferred satisfaction levels in the survey were lower than the measured thermal sensation. It is recommended that future retrofits are adequately planned and optimised to improve both IEQ and energy performance. A whole building retrofit approach must balance and include factors such as human health, building fabric and energy savings to avoid the pitfalls of current practice.

Indoor environment quality assessment in classrooms: An integrated approach

Indoor Environmental Quality is an important issue in educational buildings since it is directly related to students’ well-being and learning activities. Indoor Environmental Quality parameters have been assessed in three representative campus building typologies (old, new, and retrofitted), in Tehran, Iran, by measurements and questionnaire (n = 842) from July 2016 to April 2017. Results have been compared to the students’ overall satisfaction level and recommended standards. According to results, minimum attention to local standards with regard to Indoor Air Quality, acoustic, and lighting, especially in the old and retrofitted buildings, seems the main reason of low environmental quality in the studied cases. Fitting a multiple regression model to the questionnaire data, a mathematical model is developed to predict the overall comfort (Indoor Environmental Quality index). Studied buildings have been ranked based on the Indoor Environmental Quality index from high quality: I (building C) to out of the comfort range: IV (building A). Moreover, results reveal that the acceptable range of each Indoor Environmental Quality parameters, especially with regard to thermal and acoustic comfort, is broader in real condition in comparison with the standards. Finally, the buildings’ annual energy consumption is used to propose a Retrofit Potential Index in order to assess the impact of comfort parameters on energy consumption by integrated analyses.

Indoor environmental quality assessment, part 2: Model reliability analysis

Indoor environmental quality index involves a set of indoor environmental quality sub-components, provides an assessment of building user comfort and satisfaction and may be used as a tool to support the design of energy-efficient buildings. Unfortunately, the unknown reliability of the indoor environmental quality model is a recognized barrier for its wider practical use. In this article, a preliminary reliability test for the indoor environmental quality model is presented, providing a correct evaluation of the measurement data results and a step-by-step guide to the expression of its uncertainty. The uncertainty based on the physical parameters is first analyzed and then corrected by considering the impacts of the instability of the physical parameters. In the end, all sources of uncertainty are recognized, including uncertainties introduced by the probability distribution of panel sensory tests. A procedure for detecting internal incongruity in the indoor environmental quality model structure is also provided, and a criterion for elimination of this syndrome is proposed. Finally, in standardized indoor environment, the estimated uncertainty of the IEQindex is presented to be no less than ±17%.

‘We like to live in the weather’: Cooling practices in naturally ventilated dwellings in Darwin, Australia

To move to holistic indoor environmental quality (IEQ) assessment methods of residential building performance in Australia, a relevant evidence base on the comfort behaviour and preferences of contemporary households is needed. A lack of information on the environmental conditions, behaviour and preferences relevant to dwellings in Australia’s hot humid climates has been revealed as an area of ongoing policy and research interest. This paper explores the cooling practices of households living in predominantly naturally ventilated dwellings in Darwin, the Northern Territory through a survey of behaviour, preferences and dwelling construction (n=102) and a 12-month longitudinal thermal comfort study in 20 houses (n=2535). The results show that these households employ a range of adaptive behaviours in response to warm and hot conditions. The houses were almost always naturally ventilated, with the assistance of ceiling fans for approximately 50% of the time. The limited use of air-conditioning in these houses is more strongly associated with indoor humidity levels than temperature. These patterns of comfort behaviour provide a basis for the enhancement of building simulation models for the performance assessment of dwellings in naturally ventilated mode in hot humid climates in Australia.

Fuzzy inference system for the assessment of indoor environmental quality in a room

The aim of the project presented in this article was to design a system which allows for assessment of indoor environmental conditions, with a special consideration regarding the comfort of occupants. The system consists of two microprocessor devices with numerous sensors, as well as a PC application which includes fuzzy inference module. Fuzzy inference algorithm allows for comfort assessment based on data gathered by sensors. It can also help to analyse the efficiency of HVAC systems. The article includes description of the system's functions and selection criteria for sensors taking into account of measurands. Also described in this paper is the construction of knowledge base, based on information from environmental standards and experts' statements. The constructed system was tested and examined, to confirm its application in practical comfort assessment and to highlight the advantages of using fuzzy logic in the process of analysing measured parameters and inference, which captures the way living beings process data.

Multitrait-multimethod analysis of subjective and objective methods of indoor environmental quality assessment in buildings

Indoor environmental quality (IEQ) refers to the condition of a building’s internal environment that is related to the occupants’ health, comfort, and wellbeing. The assessment and improvement of IEQ in buildings are based on either subjective or objective assessment or the use of both measures, and in recent times, have been attracting attention due to its role in contributing to green building and sustainable environment. This study is aimed at evaluating and analysing the validity of the IEQ parameter traits as assessed using subjective and objective measures. The convergent and discriminant validity of the measured parameter traits were tested by analysing a multitrait–multimethod (MTMM) matrix using confirmatory factor analysis (CFA). The results indicated that there is no convergent validity in the IEQ parameter traits as assessed using subjective and objective methods. However, discriminant validity of the measured parameter traits was adequately supported. This clearly shows that as much as IEQ parameter traits measured through objective physical measurement and subjective occupant survey define the same concept, they cannot be taken to represent a single and same unit of measurement.

Indoor environmental quality assessment: Part 1: Choice of the indoor environmental quality sub-component models

Indoor environment quality is a relative measure of comfort perception by people exposed to the indoor conditions. It is expected that any assessment of energy performance should also include indoor comfort. This study is to review indoor environmental quality models (with respect to thermal and acoustic comfort, indoor air and lighting quality). A simplified indoor environmental quality model is also developed with consideration of EN 15251 draft ‘Guideline for using indoor environmental input parameters for the design and assessment of energy performance of buildings’. This article analyses what components should be modelled and in particular discusses the effect of different weighting schemes on the overall indoor environmental quality index. The analysis includes thermal comfort models, indoor air quality, acoustic comfort and daylight illumination versus lightning. The proposed indoor environmental quality component sub-models will give the most reliable results when the model indoor environment input data are correctly measured and disturbing influences of indoor environmental quality monitoring process are well defined and properly assessed. The final indoor environmental quality result is based on subjoining the uncertainty values achieved in panel analysis of percentage of persons dissatisfied with indoor environmental quality with corrected measurement uncertainty. All simulations for IEQindex sub-components and preliminary metrological analysis of the whole indoor environmental quality model were performed with the NIST program for Monte Carlo tests. The presented indoor environmental quality model proposal is developed to support engineers’ practice as the convenient tool for a practical assessment of building’s occupational satisfaction.