Indoor Environmental Quality Survey Research Articles

Association Between Air Microbiological Exposure With Sick Building Syndrome (SBS) among College Dormitory Students in Public University

Introduction: Microbiological pollutants in indoor air can lead to sick building syndrome (SBS). A conducive academic environment in university dormitories requires healthy indoor air quality to enhance student performance. This study aimed to determine the association between indoor air microbiological exposure and SBS among college dormitory students at a public university. Methods: A cross-sectional study was conducted among 112 male and female college dormitory students who stayed in the public university dormitory for more than three months. Respondents were given a self-administered questionnaire-based NIOSH Indoor Environmental Quality Survey. 14 houses were selected for the measurement of indoor air quality which included PM2.5, PM10, relative humidity (%), temperature (°C), air velocity (m/s), indoor bacterial concentration (cfu/m3), and indoor mould concentration (cfu/m3). Results: Higher percentages of SBS symptoms were reported among female (94.6%) college dormitory students compared to male (82.1%). A significant difference in itching symptom on the arms and forearms was found among individuals of different genders (p<0.05). Indoor air parameters such as temperature (OR = 2.56, 95% CI = 2.66-9.87), relative humidity (OR = 1.77, 95% CI = 1.54 – 5.79), indoor bacteria concentration (OR=2.28, 95% CI = 2.48 – 10.93), and indoor mould concentration (OR=2.59, 95% CI = 1.75 – 8.98) were significantly associated with the recent SBS symptoms. Multiple logistic regression showed that the most significant predictor of SBS was indoor mould concentration. Conclusion: Exposure to high concentrations of indoor bacteria and mould, high temperatures, and high relative humidity influenced the prevalence of SBS among college dormitory students. Further assessment and preventive action need to be taken to reduce the exposure of indoor air microbiological to the students.

Indoor Environmental Quality Survey in Research Institute: A Floor-by-Floor Analysis

Comprehensively monitoring indoor environmental quality (IEQ) parameters and their dynamic relations is essential to ensure improved productivity and a healthy environment for building occupants. Although IEQ significantly influences working efficiency, studies addressing this aspect with researchers in institutes as the focal point are limited. Thus, this study employed drill-down analyses, such as floor-by-floor and building-by-building examinations and used an occupant IEQ survey approach to evaluate working conditions in research buildings. This study systematically and objectively assessed IEQ using the Korea building occupant survey system. The results indicate that acoustic qualities affect the work productivity and satisfaction of the building occupants. The floor-by-floor analysis is necessary to identify IEQ factors and the reasons for the satisfaction of occupants. Additionally, it is important to improve the user-friendliness of the system, implement frequent survey distribution systems, and empirically analyze data associations among building, spatial, and demographical characteristics.

Association between Human Health and Indoor Air Pollution in Saudi Arabia: Indoor Environmental Quality Survey

In many aspects of life quality, bio-contaminants and indoor air quality have had catastrophic consequences, including a negative impact on human health with an increased prevalence of allergic respiratory reactions, asthma, and infectious diseases. We aimed to evaluate the quality of indoor air environment and find out the association between human health and indoor air pollution and also to assess the physical health status of a group of Saudi and non-Saudi populations during this pandemic. Also, we aimed to assess the most common health condition or symptoms associated with ventilation. A questionnaire was distributed online to test indoor air quality, ventilation status, common signs and symptoms of any allergy or mental status and their relationship to certain variables. A total of 362 respondents were included. Before living in the current home, flu or Influenza and chapped lips were more prevalent than allergies and chapped lips signs while living in the current home. (12.2% , 10.8% vs. 18.5% , 13.55% before and after respectively) Multiple colds were the second most common symptom (10.2%). Hoarse voice and headaches were the least common symptoms experienced; each constituted 4.4%. During the COVID-19 Pandemic, most respondents wore a facemask, approximately 76.5%; and almost one-third of respondents had bright natural light inside the current home (43.1%). The presence of natural light within the current home was significantly associated with symptoms experienced during living in the current house (p<0.05). Natural sunlight exposure could decrease allergic symptoms and minor health problems associated with poor ventilation and air quality indoors. In current living homes, the majority of respondents never used air purifiers (72.9 percent). In order to get attention from people to enhance the quality and ventilation mechanism of indoor air, special care and awareness of the effects of the use of air purifiers on human health is needed.

Indoor environmental quality and occupant satisfaction in green-certified buildings

ABSTRACT Green-building certification systems aim at improving the design and operation of buildings. However, few detailed studies have investigated whether a green rating leads to higher occupant satisfaction with indoor environmental quality (IEQ). This research builds on previous work to address this. Based on the analysis of a subset of the Center for the Built Environment Occupant Indoor Environmental Quality survey database featuring 11,243 responses from 93 Leadership in Energy and Environmental Design (LEED)-rated office buildings, this study explores the relationships between the points earned in the IEQ category and the satisfaction expressed by occupants with the qualities of their indoor environment. It was found that the achievement of a specific IEQ credit did not substantively increase satisfaction with the corresponding IEQ factor, while the rating level, and the product and version under which certification had been awarded, did not affect workplace satisfaction. There could be several reasons for this, some of which are outside the control of designers and beyond the scope of rating systems based primarily on design intent. The challenges and priorities facing building professionals, researchers and green building certification systems are discussed for the creation of more comfortable, higher performing and healthier green-rated buildings.

Comparing temperature and acoustic satisfaction in 60 radiant and all-air buildings

There is little knowledge from occupied buildings of the impact of radiant heating and cooling systems on indoor environmental quality aspects such as thermal comfort, indoor air quality, and acoustics. We present indoor environmental quality survey results from 3892 respondents in 60 office buildings located in North America; 34 of which used all-air systems and 26 of which used radiant systems as the primary conditioning system. In the current study, we present the survey results of 1645 occupants in buildings with radiant systems. To our knowledge, this is the largest dataset used in a comparison of occupant satisfaction in radiant buildings. We used an existing database to extract a subset of occupant responses from all-air buildings whose key characteristics match those radiant buildings. The results indicate that radiant and all-air spaces have equal indoor environmental quality, including acoustic satisfaction, with a tendency towards improved temperature satisfaction in radiant buildings.

Occupant satisfaction in LEED-certified higher education buildings

Purpose– The purpose of this paper is to quantify occupant satisfaction levels within Leadership in Energy and Environmental Design (LEED)-certified higher education buildings and determine the extent to which this certification helps designers to deliver successful interior environments.Design/methodology/approach– A web-based adaptation of the Center for the Built Environment's (CBE) Occupant indoor environmental quality Survey was distributed within two LEED-certified higher education buildings at a public university. Occupants were then asked to participate in interviews designed to contextualize survey results and further understand issues identified by building users. Descriptive statistics and a content analysis were utilized to determine satisfaction levels in each building.Findings– In general, LEED certification may be used as an aid for delivering successful interior environments, however, opportunities for enhancing the reliability of this tool were identified. For example, while Building A and Building B exceeded the CBE standards, neither met the 80 percent thermal comfort satisfaction rating recommended in the LEED system. Interviewees identified thermal set points, lack of thermal controls, and cold material finishes as the culprits. Based on study findings and supporting literature, suggestions are made for improving the LEED certification process and integrating post-occupancy evaluations (POEs) into the development of higher education buildings.Originality/value– This study's findings may shed some light on how LEED certification and POEs aid in the production of exemplary higher education facilities. This study helps to inform sustainable practices in higher education settings and serve as a foundation for continued research in the field of sustainable design.

Indoor Environmental Quality Survey: A Brief Comparison between Different Post Occupancy Evaluation Methods

Building occupants are important factor in giving information on indoor conditions such as comfort, productivity, building performance and occupants ́ health. Even that, being their appraisal mainly based on subjective judgments, it is difficult to set up a standard and objective method for this purpose. The present work aimed to describe, analyze and compare the most common tests on this topic, in order to highlight critical, failings and strengths.

INDOOR AIR QUALITY AND PREVALENCE OF SICK BUILDING SYNDROME AMONG OFFICE WORKERS IN TWO DIFFERENT OFFICES IN SELANGOR

This study was done to investigate the relationship between Indoor Air Quality (IAQ) and prevalence of Sick Building Syndrome (SBS) in two different offic es (old and new) in Selangor. Hundred and seventy workers were selected consist of 85 office workers for each building. Questionnaire based on Indoor Ai r Quality and Work Symptoms Survey, NIOSH, Indoor Environmental Quality Survey, 1991 was used to record prevalence of SBS. Measurement of indoor air quality was performed using instruments recommended by IAQ Code of Practice, Department of Occupational Safety and Health, Malaysia. IAQ supplied air was significantly higher in new buildi ng with the median 22.49 cfm/person while 15.79 cfm/person in old building (z = -6.23, p<0.001). Th e prevalence of SBS in old building was significant ly higher compared to the new building ( χ 2 = 30.6, p<0.001). Levels of indoor air pollutants i n old building were significantly higher compared to new building for: CO 2 (z = -4.62, p<0.001); TVOC (z = -2.71, p<0.05); PM 10 (z = -2.11, p<0.05); PM 2.5 (z = -2.35, p<0.05), meanwhile for UFP (z = 4.72, p<0.001) and THI value (z = -4.57, p<0.001), new building was si gnificantly higher compared to old building. There was significant association between the prevalence of S BS and the indoor air pollutants in the old buildin g namely CO 2 (OR = 3.56, 95% CI = 1.327-9.548); CO (OR = 4.95, 95% CI = 1.740-14.127); TVOC (OR = 4.71, 95% CI = 1.571-14.151); PM 10 (OR = 6.23, 95% CI = 2.278-17.065) and PM 2.5 (OR = 4.18, 95% CI = 1.564-11.199), while in the new building, the preva lence of SBS showed significant association with an indoor air pollutant namely UFP (OR = 6.53, 95% CI = 1.757-24.327). After controlling the cofounders; age, medical condition, smoking and having pet at h ome, the results showed that CO 2, CO, TVOC, PM 10 , PM 2.5 influenced SBS in old building while UFP influence d SBS in the new building. This study suggested that when there was an increase in the ventilation rates per person in office building, it would signi ficantly reduced prevalence of SBS, even though both buildings meet the existing ASHRAE ventilation standards for office building. Reduction in prevalence of SBS would depend on the increase in ventilation rates, ventilation effectiveness and reduction in indoor a ir pollutants that can cause SBS.

Case Study

An indoor environmental quality survey was conducted in a small private automotive repair shop during May 2009 (hot season) and February 2010 (cold season). It was established that the detached building, which is naturally ventilated and lit, had all the advantages of the temperate local climate. It provided a satisfactory microclimatic working environment, concerning the thermal and the lighting comfort, without excessive energy consumption for air-conditioning or lighting. Indoor number concentrations of particulate matter (PM) were monitored during both seasons. Their size distributions were strongly affected by the indoor activities and the air exchange rate of the building. During working hours, the average indoor/outdoor (I/O) number concentration ratio was 31 for PM0.3-1 in the hot season and 69 for the cold season. However I/O PM1-10 number concentration ratios were similar, 33 and 32 respectively, between the two seasons. The estimated indoor mass concentration of PM10 for the two seasons was on average 0.68 mg m−3 and 1.19 mg m−3, i.e., 22 and 36 times higher than outdoors, during the hot and the cold seasons, respectively. This is indicative that indoor air pollution may adversely affect mechanics’ health. Noise levels were highly variable and the average LEX, 8 h of 69.3 dB(A) was below the European Union exposure limit value 87db (A). Noise originated from the use of manual hammers, the revving up of engines, and the closing of car doors or hoods. Octave band analysis indicated that the prevailing noise frequencies were in the area of the maximum ear sensitivity.

Occupant satisfaction in LEED and non-LEED certified buildings

Occupant satisfaction with indoor environmental quality (IEQ) in office buildings has been positively correlated to self-estimated job performance and, potentially, to overall company productivity. LEED is a voluntary, consensus-based, market-driven program that provides third-party certification of green buildings, contributing to promote sustainability into the mainstream of building design and construction. From the literature, however, it is unclear the extent to which LEED certification also improves occupant satisfaction with IEQ. The aim of this paper is to study if LEED certified buildings lead to a higher, equal or lower satisfaction with indoor environmental quality than non-LEED rated buildings. Occupant satisfaction has been evaluated on a subset of the Center for the Built Environment Occupant Indoor Environmental Quality Survey database featuring 144 buildings (65 LEED certified) and 21,477 individual occupant responses (10,129 in LEED buildings). Differently from previous studies of the CBE database, the results show that occupants of LEED certified buildings have equal satisfaction with the building overall and with the workspace than occupants of non-LEED rated buildings. The difference in mean satisfaction scores between LEED and non-LEED buildings for other 15 IEQ parameters investigated is always lower than 6% with a negligible effect size. Therefore, it can be concluded that there is not a significant influence of LEED certification on occupant satisfaction with indoor environmental quality, although the analysis of mean votes of satisfaction reveals that occupants of LEED buildings tend to be slightly more satisfied with air quality, and slightly more dissatisfied with amount of light.

CO2–Based Demand–Controlled Ventilation and Its Implications for Interior Design

CO2–based demand–controlled ventilation (DCV) is a ventilation method that resets outdoor air supply rates using CO2 as an operating parameter ( ASHRAE, 2007a ). Even though CO2 itself is not harmful, high levels of CO2 concentration in indoor environments displace oxygen in the air and can cause a deficiency of oxygen for breathing. The most important aspect of CO2 in DCV is that it is a good indicator of occupancy in indoor spaces. Therefore, CO2 is an effective parameter for controlling ventilation based on occupancy level. CO2–based DCV has been increasingly used in recent years to optimize the energy consumption in ventilation systems as technological advances make its implementation more feasible and interest in environmentally responsible building design grows. This study aims to provide information about CO2–based DCV and suggest implications for interior design practitioners and educators. To achieve this purpose, this study reviewed previous studies and examined the current practices in CO2–based DCV in order to suggest guidelines for CO2–based DCV implementation for interior designers. The guidelines focused on proper CO2 sensor location design, taking into consideration the activities and other equipment in the room. In addition, a study of CO2–based DCV in the lecture halls of a university campus was conducted. Physical measurements were done in the lecture halls, and trends data were collected from the university's facility management department to compare the measurements. A perceived indoor environmental quality survey was also done to explore the occupants’ responses about CO2–based DCV.

Listening to the occupants: a Web-based indoor environmental quality survey

Building occupants are a rich source of information about indoor environmental quality and its effect on comfort and productivity. The Center for the Built Environment has developed a Web-based survey and accompanying online reporting tools to quickly and inexpensively gather, process and present this information. The core questions assess occupant satisfaction with the following IEQ areas: office layout, office furnishings, thermal comfort, indoor air quality, lighting, acoustics, and building cleanliness and maintenance. The survey can be used to assess the performance of a building, identify areas needing improvement, and provide useful feedback to designers and operators about specific aspects of building design features and operating strategies. The survey has been extensively tested and refined and has been conducted in more than 70 buildings, creating a rapidly growing database of standardized survey data that is used for benchmarking. We present three case studies that demonstrate different applications of the survey: a pre/post analysis of occupants moving to a new building, a survey used in conjunction with physical measurements to determine how environmental factors affect occupants' perceived comfort and productivity levels, and a benchmarking example of using the survey to establish how new buildings are meeting a client's design objectives. In addition to its use in benchmarking a building's performance against other buildings, the CBE survey can be used as a diagnostic tool to identify specific problems and their sources. Whenever a respondent indicates dissatisfaction with an aspect of building performance, a branching page follows with more detailed questions about the nature of the problem. This systematically collected information provides a good resource for solving indoor environmental problems in the building. By repeating the survey after a problem has been corrected it is also possible to assess the effectiveness of the solution.