Investigation Of Indoor Air Quality Research Articles

Investigation of indoor air quality in painting studios and health risk assessment

ABSTRACT Indoor pollutants risk the health of people who spend about 90% of their time indoors. Studies have shown that volatile organic compounds (VOCs), which are among these pollutants, can cause asthma and allergies as well as various types of cancer. This study aimed to evaluate the indoor air quality of painting studios and determine the health risk factors for human health. In the survey conducted for 6 weeks, indoor pollutants were measured for three painting studios. In addition, VOC types were determined by Thermal Desorber-Gas Chromatography (TD-GC-MS) analysis in the samples taken on Tenax TA sorbent by active sampling method. The results showed that TVOC and CO₂ values indoors are up to 1.5 and 2.2 times higher than outdoors, respectively. The total cancer risk was found to be higher than the acceptable limit, with a value of 1.60E–06.

Field investigation of indoor air quality and its association with heating lifestyles among older people in severe cold rural China

Field investigation of indoor air quality and its association with heating lifestyles among older people in severe cold rural China

Changes in Indoor Air Quality in Public Facilities before and after the Enactment of Taiwan’s Indoor Air Quality Management Act

South Korea was the first to administer the Indoor Air Quality Control Act in 1996, followed by Taiwan’s implementation in 2012. This study investigated indoor air quality (IAQ) in public facilities before and after the enactment of Taiwan’s Indoor Air Quality Management (IAQM) Act in 2012 to assess the effectiveness of the Act. The study also calculates health risks for employers, and consumers/visitors separately. The mean concentration of carbon dioxide (CO2) after the IAQM Act’s enactment was higher than before, except for government offices. The lowest attainment rates for CO2, below 80%, were 73% in hospitals and 78% in libraries. As for formaldehyde, average concentrations were higher after the IAQM Act’s implementation, except for the exhibition room and library. Notably, improvements in particulate matter with a diameter less than 2.5 μm (PM2.5) levels were evident in hospitals and libraries compared to other environments (attainment rates increased from 85% to 100% and 89% to 94%, respectively). However, in schools, preschools, and public transport spaces, unattainment rates worsened. Regarding cancer risk from formaldehyde exposure in the public, the 95% of upper risk limits ranged from 3.44×10−5 in the public transport system to 8.80×10−4 in preschools. Our findings highlight the necessity of integrating more measurement data after IAQM Act implementation and formulating management strategies based on risk assessments for future investigations.

Investigation of indoor noise pollution level and air quality of furniture manufacturers

Indoor air quality has become a more prominent concern since the arrival of the COVID-19 pandemic. Manufacturing industries have always been prone to occupational health risks, which depend on the dynamics of the production shop floors. The furniture industry is one of these sectors with a unique work environment. Although a typical furniture manufacturing facility involves physical, chemical, and noise pollution-producing elements, this industry has been studied relatively less for indoor air quality and noise-related risks. This study investigated nine furniture manufacturing organizations’ indoor air quality and noise pollution levels through comprehensive quantitative techniques. The results of the measurements were compared against reference values set by specific guidelines to explore the degree of occupational health risk associated with the World Health Organization’s (WHO) suggested levels. Repetitive measurements from five pre-designated workstations were taken at each facility. The study’s results indicated that organization size and department were significant factors for PM 2.5 and HCHO parameters, while only department type was substantial for noise exposure levels. However, across all departments and organization sizes, LAeq noise levels were below the safety threshold of 85 dB(A). Most organizations presented a lack of proper use of personal protective equipment and poor ventilation across shop floors.

Investigation of indoor air quality and pulmonary function status among power loom industry workers in Tamil Nadu, South India

Investigation of indoor air quality and pulmonary function status among power loom industry workers in Tamil Nadu, South India

Numerical investigation of indoor thermal comfort and air quality for an office equipped with corner impinging jet ventilation

ABSTRACT This study investigates the feasibility of using only corner impinging jet ventilation (CIJV) for heating and cooling a medium-sized office space with two occupants while maintaining adequate indoor thermal comfort and air quality compared to traditional mixing ventilation systems. This study examines what impact various outdoor temperatures, ranging from −15°C to 25°C, have on an office environment in terms of indoor thermal comfort and air quality. Three different workspace positions were evaluated. The results show that the CIJV system meets the ASHRAE thermal comfort standards for all three positions. In terms of indoor air quality, CIJV performs better than traditional mixing systems, with improved mean age of air and ACE values. This study concludes that CIJV can be used both close and far away from the supply inlets and still provide adequate indoor thermal comfort and air quality during both cooling and heating season.

Investigation of indoor air quality in coal-heating rural residential buildings in Northern China based on longtime monitoring

Indoor air quality (IAQ) is closely related to resident health and has been drawing extensive consideration from academics as well as government regulators. However, few studies have quantitatively investigated IAQ in rural buildings during the heating period, in which the resident time indoors is relatively longer. This study has monitored and quantitatively analyzed the indoor air parameters (temperature, CO2, formaldehyde and PM2.5) of 20 rural houses in Northern China during the heating season (15 days out of 120). After quantitatively analyzing the IAQ parameters, the Pearson correlation model was also adopted to evaluate the relationships between them. Results showed that only 4 households could keep the indoor temperature above 18°C for more than 50% of the heating period. Additionally, there were 7, 2 and 18 households, of which the over-standard time of CO2, formaldehyde and PM2.5 took up more than 40%. The concentration of indoor PM2.5 was higher than outdoors most of the time. Therefore, indoor PM2.5 was mainly caused by indoor activities rather than transported from outside. Correlation analysis showed that CO2 was positively correlated with formaldehyde and PM2.5 in 16 and 12 households.

Investigation of Indoor Air Quality by Incorporating Sewage Sludge Waste into Fired Clay Brick

Generally, the production of sewage sludge waste has increased due to rapid growth of the population. Due to that, the disposal method has become crucial issues nowadays. Therefore, this research focuses on the investigation of indoor air quality of fired clay brick incorporating with sewage sludge. The bricks were incorporated with 0% and 5% of two type of sewage sludge and fired at 1050°C with heating rates 1°C/min. The experiment of Indoor Air Quality was obtained by measuring gases emissions of total volatile organic compound (TVOC), carbon dioxide (CO2), carbon monoxide (CO), ozone (O3), formaldehyde (HCHO) and particulate matter (PM10) and were compared with Industry Code of Practice on Indoor Air Quality requirement standard. From the result shows that by incorporation of 5% of sewage sludge into fired clay brick complied with the standard requirement for building material usage with no negative effect to the environment. As the conclusions, the use of sewage sludge as clay replacement reduces the waste disposal in landfills and produce the low-cost building materials.

Numerical investigation of indoor air quality in health care facilities: A case study of an intensive care unit

The risk of healthcare-associated infections (HAIs) is higher in patients admitted to intensive care units (ICU) and high dependency units (HDU). Currently, most ventilation studies focus on specialized areas, mainly isolation rooms and operating rooms. This paper focuses on the ventilation of multiple-bed hospital wards in developing countries. This study uses computational fluid dynamics (CFD) simulation to model and investigate airflow and the spread of pollutants. The study aims to investigate ICUs with various ventilation system designs. These predicted behaviors and characteristics were compared numerically to determine compliance with the requirements of airflow patterns, airborne contaminant distribution, and current international standards. The case study simulations were carried out using ANSYS Fluent simulation software as a solution tool. Three different ventilation systems, Vertical Laminar Airflow Ventilation (VLAF), Horizontal Laminar Airflow Ventilation (HLAF), and Temperature-Controlled Airflow Ventilation (TcAF), were modeled within five different designs to determine the most effective possible distribution of air inside the patient's room, based on different categories, primarily temperature distribution, CO2 concentration, and airflow distribution. The authors applied the TcAF technique in an ICU room, comparing the results of the proposed technique with those of other common techniques (HLAF and VLAF). It was found that TcAF showed the most effective airflow distribution around patients, isolating each patient from the others. However, the temperature distribution was excluded from the ASHRAE standard. HLAF with two exhausts is the most suitable option, with a lower CO2 concentration than the alternatives and a temperature that meets ASHRAE standards.

Indoor Air Quality and Smoking Control in Healthcare Environments in Northern China

Background: Air pollution has adverse effects on human health, while people experience regular contact with air pollutants in a high concentration via inhalation and ingestion. Nowadays, the average person spends more than 90% of their lifetime inside both private and public buildings, and this figure can reach close to 100% for the sick or elderly who cannot take care of themselves. Attention should be paid to indoor air quality (IAQ), especially for certain groups in specific places. Purpose: This study intends to investigate indoor air quality in a large general hospital in Northern China, where people desire clean air for good nursing, and then propose solutions to any air pollution present. Methods: Some influential factors related to air pollution, including PM2.5 and PM10, were measured in winter. Observations were applied to indicate that the smoking behaviors of medical staff were an important contributor to air pollution. Experimental measurements were designed to test the concentration of airborne nicotine. Questionnaire surveys and follow-up interviews were conducted to understand attitudes towards smoking behaviors and offer design strategies. Results: The scopes of 24 h mean concentrations of PM2.5 (10.2~57.8 µg/m3, 17.5~45.5 µg/m3, and 20.5~91.1 µg/m3) and PM10 (17.7~81.8 µg/m3, 13.0~83.8 µg/m3, and 31.7~188.1 µg/m3) exceeded relevant guideline values, and the airborne nicotine concentrations (1.29 µg/m3 and 1.62 µg/m3) confirmed that smoking behaviors occurred in the consulting room. Conclusions: To control tobacco to ensure good indoor air quality, smoking behaviors should be managed instead of forbidden. This will also provide greater satisfaction to medical staff. Smoking behavior management requires a comprehensive consideration based on ambient conditions and psychological demands. As there is a lack of specific requirements in relevant design regulations that are tailored to ensure the environmental satisfaction of medical staff, the findings from this study can be used as evidence to inform the design of healthcare environments for public health in future.

Investigation of indoor air quality in university residences using low-cost sensors

Indoor air quality (IAQ) is crucial for the wellbeing of university students. Yet, IAQ in student residences is highly variable and challenging to monitor. This work is the first to monitor IAQ in student residence with a low-cost sensor network.

Investigation of Indoor Air Quality in Natural Ventilated Classroom in Perlis

Indoor air pollutants have been linked to many health effects in humans and particularly children who are more vulnerable to the poor IAQ. This study presents quantitative assessment of IAQ in the selected primary schools in Perlis that is situated at northern peninsular of Malaysia. The objectives of this study was to investigate indoor air quality and comfort parameters in the natural ventilated school classroom in Perlis. A real-time monitoring method that was derived from Industry Code of Practice on IAQ 2010 by Department of Occupational Safety and Health (DOSH) was used in this research. IAQ monitoring was conducted using Aeroqual Series 500, Tactical Air Sampler, SKC Aircheck XR5000, Elitech Rc-4 and UT363BT Anemometer were carried out at two primary schools which are SK Seri Perlis and SK Putra. Selected parameters such as respirable particulates (PM10), total volatile organic compound (TVOC), formaldehyde (CH2O), carbon monoxide (CO), ozone (O3), temperature, relative humidity and velocity were measured for two months period. The IAQ monitoring results revealed that the air pollutants were recorded higher in SK Seri Perlis compared to SK Putra due to its location that is nearby roadside. The examined pollutants concentration such as PM10, CO, and O3 were within the acceptable limits of Industry Code of Practice on Indoor Air Quality (2010) by DOSH, while CH2O, temperature, relative humidity and velocity were detected higher than the acceptable limits.

Factors influencing indoor air pollution in buildings using PCA-LMBP neural network: A case study of a university campus

This study investigated indoor air quality (IAQ) and its association with building characteristics and environmental factors in eleven different campus buildings in Gainesville, Florida. Integrated indoor and outdoor sensor systems are built and installed to measure the levels of airborne particulate matter (PM2.5 and PM10), nitrogen dioxide (NO2), ozone (O3), relative humidity (RH), and temperature continuously in 10 min intervals for two weeks for each case building. Twenty building-related characteristics were collected through a walkthrough-based survey, HVAC historical data, and construction drawings. Through these data, a PCA-assisted Levenberg-Marquardt Backpropagation (LMBP) neural network model was developed for rapidly and accurately analyzing and predicting the interaction between IAQ and its affecting factors. Factors with significant contributions to indoor exposure were may mostly be determined by outdoor sources. This is evidenced by the strong associations that were found between indoor PM(2.5-10) and O3 values and their corresponding outdoor values and factors, including distance from the major traffic (DFMT), cracks occurring, outdoor temperature, and humidity. Indoor NO2 concentrations were affected by DFMT, indoor O3, indoor RH, number of air grilles, room volume, and window-to-wall ratio. Also, the comparison shows that the PCA-LMBP model outperforms the traditional BP-ANN and multi-linear regression methods. The average values of 1.34, 2.53, and 4.86 were obtained for the root-mean-square error (RMSE) of PCA-LMBP, BP-ANN, and MLR models, respectively. These results can be accordingly referred for the follow-up studies that analyze IAQ in similar building and environmental conditions.

Investigation of Indoor Air Quality in Residential Buildings by Measuring CO2 Concentration and a Questionnaire Survey.

Indoor air quality (IAQ) in houses is often deteriorated by chemical substances emitted from heating, building materials, or other household goods. Since it is difficult for occupants to recognize air pollution, they rarely understand the actual conditions of the IAQ. An investigation into the actual condition of IAQ in houses was therefore conducted in this study. Carbon dioxide () concentrations in 24 occupied houses was measured, and the results from our analysis showed that the use of combustion heaters increased the concentration of and led to indoor air pollution. Results indicate that as outdoor temperature decreased, the frequency of ventilation decreased simultaneously, and concentration increased. Results of the questionnaire survey revealed that the actual IAQ in each house did not match the level of awareness its occupants had regarding ventilation. Along with this difficulty in perceiving air pollution, the lack of knowledge about ventilation systems and the effects of combustion heating may be additional barriers to IAQ awareness.

Investigation of Indoor Air Quality and Thermal Comfort of a College Building in Hyderabad, India

The aim of this present study is to investigate the indoor air quality (IAQ) and thermal comfort (TC) of the class and faculty rooms at a college in Hyderabad, India. The concentrations of air pollution at class and faculty rooms available across four floors were determined with the help of indoor air quality monitoring equipment. The measurements were conducted continuously in the indoor and outdoor environment for 07 months with the variation in two different seasons such as monsoon and winter. The collected data were analyzed and compared with the Indian green building code (IGBC). Different parameters such as temperature, carbon dioxide (CO2), carbon mono-oxide (CO), oxygen (O2), total volatile organic compounds (TVOC), and particulate matter (PM 2.5 & 10) were analyzed.The mean concentrations of PM 2.5 in all four floors were slightly above the IGBC standards in monsoon seasons and higher in winter seasons. Indoor PM 10 was higher as per IGBC in the winter season as compared with that in monsoon season. TVOC, CO, and CO2 showed significantly higher in class and faculty rooms of all the four floors in both seasons. The predicted mean vote (PMV) index shows a significantly cold when compared with the thermal sensation scale which can accelerate the respiratory tract infectious diseases. Each floor shows different concentration levels of all the above-mentioned IAQ parameters.A questionnaire was developed, and a survey was conducted to analyze the comfort indices and responsible conditions for dissatisfactory factors. The results obtained from the daily monitoring parameters were compared with the survey questionnaire. The inferences were developed based on the PM 2.5 & 10 and CO2 concentration levels. Based on the obtained inferences and as per the IGBC standards specific suggestions were given to alter the building physiology.

Investigation of air pollution mitigation measures, ventilation, and indoor air quality at three schools in London

In UK urban areas, due to ease of accessibility and convenience, many schools are located close to main busy roads. This often results in pollution hotspots around schools due to on-road vehicular pollutant emissions, especially during drop-off and pick-up times of students to and from schools. As well as being exposed to air pollutants in the school grounds, students are also exposed indoors. Thus, the need for scientific investigations focusing on mitigation of air pollution exposure indoors and outdoors for schools has significantly increased. The main objectives of the present study were therefore to: 1) obtain a clearer understanding of the extent of the air pollution problem inside and around schools and the factors that affect it; and 2) determine how it may be mitigated effectively using a range of interventions. These were achieved by carrying out monitoring of air pollution and associated parameters in and around three primary schools in London, UK. The study investigated the exposure reduction potential of various interventions, such as green screens, air purifiers, and school streets. A good understanding was obtained of the improvement in air quality that was achieved by the interventions both inside and outside the classrooms in the three schools. A green screen along the fences of the school reduced PM concentration by up to 44% in the playground. Installing air purifiers in a classroom resulted in lowering in PM concentration of about 57%. The school street initiative decreased PM concentration by about 36% in front of the school during pick up time. From the overall findings, practical recommendations have been included, as far as has been possible, that will enable formal guidance to be produced to help improve air quality in and around UK schools.

Investigation of indoor and outdoor air quality in a university campus during COVID-19 lock down period

The pandemic of COVID-19 currently shadows the world; the whole earth has been on an unprecedented lockdown. Social distancing among people interrupted domestic and international air traffic, suspended industrial productions and economic activities, and had various far-reaching and undetermined implications on air quality. Improvement in air quality has been reported in many cities during the lockdown. On March 22, 2020, the Turkish government enforced strict lockdown measures to reduce coronavirus disease transmission. This lockdown had a significant impact on the movement of people within the country, which resulted in a major drop in worldwide commercial activities. During this period, university campuses were emptied due to the transition to distance education. In this study, various air pollutants sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), fine particulate matter (PM2.5), total bacteria, and total fungi were measured in different indoor environments at Eskişehir Technical University Campus in Eskişehir, Turkey during COVID-19 lock down period. Also, to calculate the indoor and outdoor ratios (I/O) of the pollutants, simultaneous outdoor measurements were also carried out. The average indoor SO2, NO2, O3, and PM2.5 concentrations in different indoor environments ranged between 2.10 and 54.58, 1.36–30.89, 12.01–39.05, and 21–94 μg/m3, respectively. The total number of bacteria and fungi ranged between 21.83-514.15 and 13.10–83.36 CFU/m3, respectively. Our study intends to give a glimpse to quantify the impact of a pandemic on air quality in different indoor environments in a university campus in Eskişehir, Turkey and calls for follow-up studies. Indoor concentrations were evaluated together with outdoor concentrations. In general, it can be said that the calculated I/O ratios for SO2, NO2, O3, bacteria, and fungi were less than 1 in most indoor environments.

An Assessment of Indoor Air Quality (IAQ) in Foundry Laboratory

Abstract Indoor Air Quality (IAQ) is an important element for a healthy working environment. Working in poor IAQ can lead to sick building syndrome (SBS) with symptoms and troublesome to concentrate in delivering the task. In this study, a preliminary IAQ investigation was carried out at a teaching foundry facility of a higher learning institution in Malaysia. The foundry processes are known to discharge pollutants and gasses. Therefore, this assessment was used to investigate the existence of harmful gasses including Carbon Dioxide (CO2), Carbon Monoxide (CO), particulate matter (PM), and Volatile Organic Compound (VOC) throughout the complete foundry process cycle. An advanced environmental monitor kit was used to monitor the air quality at three different locations within the foundry space to get a good distribution of data. The results reveal that only CO2 and PM10 traces were detected with the reading is still within the allowable range based on guidelines from the Department of Occupational Safety and Health (DOSH), Malaysia. As for thermal comfort result, the Temperature and Relative Humidity (RH) was found to exceeds the benchmark value. Therefore, a more comprehensive and detail thermal comfort study should be conducted to validate the current finding and an appropriate mitigation strategy must be put in place to ensure the thermal comfort of the occupants during the teaching and learning process in the foundry can be improved.

Investigation of indoor air quality in university libraries in terms of gaseous and particulate pollutants in Bartin, Turkey.

Indoor air quality (IAQ) was investigated in two libraries of Bartin University. Particle matter, TVOC, and CH2O were measured simultaneously in different rooms of the libraries. Measurements were made by PCE-RCM 11 measuring device. They were conducted monthly between September 2019 and October 2020 for 2 weeks for each library. TVOC mean concentration was higher than the limit value reported by Seifert et al. (1999). PM2.5 and PM10 concentrations were higher in winter unlike TVOC and CH2O concentrations. The indoor seconder blowing dust was detected to be the most important source of particulate matter in the indoor environment. On the other hand, it was thought that the pollutants in the gas phase were affected by indoor and outdoor air temperature, indoor/outdoor air exchange rate, and indoor/outdoor pollutant sources. The parameters changed during the day and in different rooms of the libraries. Pollutants did not pose any hazard on human health, since the calculated HQ and HI ≤ 1 for both exposure groups. The indoor air of the libraries was detected to be slightly polluted and bad according to the IAQI and IEI, respectively. On the other hand, the indoor air quality of the libraries was good in terms of all parameters according to the IAQC.Supplementary informationThe online version contains supplementary material available at 10.1007/s10661-022-09818-8.

Investigations of indoor air quality for office buildings in different climate zones of China by subjective survey and field measurement

This study investigated the indoor air environment of office buildings in different climate zones of China, including the indoor air pollutant concentrations, and its associated interactions with the staffs' feelings and health symptoms, which could provide basis to improve the indoor environments of office buildings. Thermal parameters and pollutant (including CO2, formaldehyde and TVOC) concentrations were monitored in different floors of sampled office buildings. Questionnaire were also surveyed to investigate humans' perception to the indoor air quality and the associated sick building syndrome. Furthermore, cancer risk assessments of these office buildings were carried out based on onsite air pollutants data. The results showed that indoor and outdoor pollutant concentrations are highly correlated, and the pollutants concentration levels vary over the time of the day, with poor indoor conditions observed in the morning and the afternoon. The questionnaire results suggested that actions should be taken to improve the indoor air environment of office buildings, and ventilation appears to be the most desirable strategy. The risk assessment results showed that health problems could exist even though the pollutant concentration levels in the indoor environment were within the standard limits. This paper investigated the discomfort reasons in the office buildings by providing pollutant concentrations and health risk assessment data together with information about the human's perception on the indoor environment. Finally, we noted that outdoor fresh air with purifiers/filters should be used to reduce the indoor pollutant concentrations.