Health Of Building Occupants Research Articles

Indoor air quality assessment to design a model for indoor air quality management and health impact assessment in Northern Thailand

Indoor air quality (IAQ) has become an important area of concern these days and tends to be more serious to human health as well as resident convenience, especially in smoke haze season (February - April) in Upper Northern Thailand (UNT). Indoor air monitoring and model development for controlling the air quality indoors is necessary for all buildings, particularly in urban areas and polluted areas. This study aims i) to study indoor air quality, ii) to assess health impacts and factors related to indoor air quality, and iii) to develop an effective model for controlling indoor air quality in Sub-district Health Promoting Hospital (HP) and Early Childhood Development Center (ED). Temperature, relative humidity, air movement, PM2.5, PM10, Carbon Dioxide (CO2), Carbon Monoxide (CO), Ozone (O3), Formaldehyde (CH2O), Total Volatile Organic Compound (TVOC), Total bacterial and fungal were used to evaluate indoor air quality. It was found that PM2.5 and PM10 concentrations in all buildings exceeded indoor air quality standards. Moreover, CO2 concentration was higher than recommended levels, especially during the daytime. HP and ED found high values of total bacteria and total fungi, which were higher than recommended level. The indoor air quality management model of a clean room that involved with the calculation of total airflow in cubic feet per hour was created and a specific size of air cleaner for the room was selected. The results showed that PM2.5 and PM10 concentrations including other parameters of the selected rooms were reduced to the recommended levels after implementing the rooms. This result indicated the effectiveness of developing an indoor air quality management model. Thus, this model can be used as a successful study case for other HP and ED, leading to a positive impact on building occupant health.

Occupant health in buildings: Impact of the COVID-19 pandemic on the opinions of building professionals and implications on research

The objectives of this study are to investigate building professionals' experience, awareness, and interest in occupant health in buildings, and to assess the impact of the COVID-19 pandemic on their opinions, as well as to compare the research on occupant health in buildings to professionals' opinions. To address these objectives, a mixed research methodology, including a thorough review of the literature (NL = 190) and an online survey (NS = 274), was utilized. In general, there is an increasing research interest in occupant health and a heightened interest in health-related projects, among professionals, following the COVID-19 pandemic. Specifically, among the nine different building attributes examined, indoor air quality was the most researched building attribute with a focus on occupant health and was also presumed to be the most important by the professionals. Professionals considered fatigue and musculoskeletal pain to be the most important physical well-being issues, and stress, anxiety, and depression to be the most important mental well-being issues that need to be the focus of design, construction, and operation of buildings to support and promote occupant health, while eye-related symptoms and loss of concentration were the most researched physical and mental well-being symptoms in the literature, respectively. Finally, professionals indicated that COVID-19 pandemic had significant effect on their perspectives regarding buildings’ impact on occupant health and they believed future building design, construction and operation will focus more on occupant health because of the pandemic experience.

The Role of Building Sector in Preserving Occupant Health for A Sustainable Development: A Review

There has been a dramatic rise in research on sustainable development but limited attention is given to human aspects such as their needs and requirements in a sustainable building. The majority of people spend their time mostly indoor, either for working, studying or living. Therefore, it is important to understand the health implications of building on occupants. The impact of indoor environment on occupant health has been largely disregarded. It should be part of the main agenda in progressing towards sustainable development. This paper aimed to discuss the interplay between indoor environment and occupant health and highlighted the role of building sector in preserving occupant health to ensure that buildings can be optimised for the benefit of occupants. A literature search on published works of indoor environment and occupant health has identified four indoor environment parameters that contribute to occupant health. These include indoor air quality, indoor lighting, indoor cleanliness and ergonomic. The impacts of each indoor environment parameter on occupant health were discussed in this paper. The findings will serve as reference for policy makers to preserve occupant health in buildings and as enhancement strategies for sustainable building development to fulfil the human requirements.

Ten questions concerning occupant health in buildings during normal operations and extreme events including the COVID-19 pandemic

Even before the COVID-19 pandemic, people spent on average around 90% of their time indoors. Now more than ever, with work-from-home orders in place, it is crucial that we radically rethink the design and operation of buildings. Indoor Environmental Quality (IEQ) directly affects the comfort and well-being of occupants. When IEQ is compromised, occupants are at increased risk for many diseases that are exacerbated by both social and economic forces. In the U.S. alone, the annual cost attributed to sick building syndrome in commercial workplaces is estimated to be between $10 billion to $70 billion. It is imperative to understand how parameters that drive IEQ can be designed properly and how buildings can be operated to provide ideal IEQ to safeguard health. While IEQ is a fertile area of scholarship, there is a pressing need for a systematic understanding of how IEQ factors impact occupant health. During extreme events, such as a global pandemic, designers, facility managers, and occupants need pragmatic guidance on reducing health risks in buildings. This paper answers ten questions that explore the effects of buildings on the health of occupants. The study establishes a foundation for future work and provides insights for new research directions and discoveries.

Concentration characteristics of ozone and product for indoor occupant surface chemical reaction under displacement ventilation

Indoor chemical reaction occurring between ozone (O3) and occupant surfaces (skin, hair, and clothing) is an important source of volatile organic compounds (VOCs) in the indoor air. This kind of chemical reaction can bring obvious impact on indoor air quality (IAQ) and building occupant health. Theoretical model describing indoor occupant surface chemical reaction between O3 and Squalene, heat and mass transfer was established and verified by indoor environment experiment in this present study. Meanwhile, in order to obtain variation characteristics of ozone and product concentration in typical indoor space, four kinds of factors were taken into account and their influence on occupant surface chemical reaction under displacement ventilation was analyzed by means of numerical simulation, including air exchange rate (ACH), ozone concentration in supplied air, squalene concentration on occupant surface, chemical reaction rate. The results show that the rising of ACH is one favorite method for reducing the exposure concentration of product (secondary pollutant) under displacement ventilation. Moreover, as to ventilation system design and its commissioning, it’s very necessary to reduce ozone concentration in supplied air by reasonable measures. In addition, lower squalene concentration on occupant surface and chemical reaction rate are very meaningful for improving IAQ during ventilation process.

Buildings, Beneficial Microbes, and Health

Bacteria and fungi in buildings exert an influence on the human microbiome through aerosol deposition, surface contact, and human and animal interactions. As the identities and functions of beneficial human microbes emerge, the consequences of building design, operation, and function must be understood to maintain the health of occupants in buildings.

Features of Indoor Human Surface Chemical Reaction under Displacement Ventilation

Ozone reactions with human surfaces (skin, hair, and clothing) are an important source of volatile organic compounds in the indoor air, which play an important role in indoor air quality and building occupant health. It's the purpose of this study to obtain the characteristics of air change rate (ACH) and reactants concentration impacting human surface chemical reaction, which is very necessary and meaningful for guiding how to improve indoor air quality (IAQ). Theoretical model describing indoor human surface chemical reaction between O3 and Squalene, heat and mass transfer was established and verified. Meanwhile, three kinds of factors were taken into account and their influence on human surface chemical reaction under displacement ventilation was analyzed for typical building space. The results show that the rising of ACH is benefit for reducing the exposure concentration of product (secondary pollutant) under displacement ventilation. Moreover, lowering ozone concentration in supplied air and squalene concentration in human surface is very meaningful for improving IAQ.

Performance of a biological degradation method for indoor formaldehyde removal

Formaldehyde is a common gaseous pollutant affecting the indoor air quality and the health of occupants in buildings. Various technologies have been tried, such as adsorption, photocatalytic oxidization and botanical filtrations. However, the removal of indoor formaldehyde is still a challenging problem due to the low rate, byproduct formation and low efficiency of the above mentioned methods. Biological degradation technology with high removal efficiency has been successfully applied in industries for effluents and waste gas treatments. However, the potential biohazard risk from possible microorganism leakages of the biological system is the biggest concern of indoor air biofiltration systems. This study investigated the performance of a biological degradation system for formaldehyde removal at typical indoor condition. A microbial immobilization method was applied in the biofiltration system to reduce the potential biohazard risk. Bacterial strain of Pseudomonas putida was embedded in calcium alginate gel, which was then formed to a novel packing material called microbial granules. To investigate the operating performance of the biofilter in practical indoor environment, the concentrations of experimental inlet formaldehyde was controlled between 0.222 and 1.339 mg m−3, while the corresponding removal efficiency of the biofilter system varied from 68.6% to 93.5%. The pressure drop was maintained at 120 Pa with air flow rate increased up to 1.5 L min−1. The effect of inlet concentration, empty bed residence time, and nutrient feeding rate on the performance of the system was investigated as well. No microbial leakages were detected at air downstream during the experimental study, while the high microbial activity of bacteria entrapped in the packing material was observed.

Outdoor ozone and building-related symptoms in the BASE study

Reactions between ozone and indoor contaminants may influence human health and indoor air quality. The U.S. EPA Building Assessment Survey and Evaluation (BASE) study data were analyzed for associations between ambient ozone concentrations and building-related symptom (BRS) prevalence. Multiple logistic regression (MLR) models, adjusted for personal, workplace, and environmental variables, revealed positive relationships (P < 0.05) between ambient ozone concentrations and upper respiratory (UR), dry eyes, neurological and headache BRS (odds ratios ranged from 1.03 to 1.04 per 10 mug/m(3) increase in ambient ozone concentrations). Other BRS had marginally significant relationships with ambient ozone (P < 0.10). A linear dose-response in UR symptoms was observed with increasing ambient ozone (P = 0.03); most other symptoms showed similar but not statistically significant trends. Ambient ozone correlated with indoor concentrations of some aldehydes, a pattern suggesting the occurrence of indoor ozone chemistry. Coupled with the MLR ambient ozone-BRS analysis, this correlation is consistent with the hypothesis that ozone-initiated indoor reactions play an important role in indoor air quality and building occupant health. Replication with increased statistical power and with longitudinal data is needed. If the observed associations are confirmed as causal, ventilation system ozone removal technologies could reduce UR BRS prevalence when higher ambient ozone levels are present. This paper provides strong statistical evidence that supports (but does not prove) the hypothesis that ozone entrained into buildings from the outdoor air is involved in increasing the frequency that occupants experience and a range of upper and lower respiratory, mucosal and neurological symptoms by as much as a factor of 2 when ambient ozone levels increase from those found in low-ozone regions to those typical of high-ozone regions. Although replication is needed, the implication is that reducing the amount of ozone entrained into building ventilation systems, either by ambient pollution reduction or engineered gas-phase filtration, may substantially reduce the prevalence of these symptoms experienced by occupants.

Airborne Infection Control in Health Care Facilities

Documented correlations between building occupant health effects and exposure to indoor airborne contaminants are very limited because of low indoor concentrations and confounding exposure elsewhere. However, an important exception has been found in hospitals where immune compromised patient mortality has been directly linked to increased indoor airborne fungal contamination caused by construction activity. Inhalation of viable Aspergillus spores often results in invasive pulmonary aspergillosis, a disease with a high fatality rate. A review of the literature is given and recommendations and needs are outlined for barriers, filtration, air pressure control and bioaerosol sensors.