Indoor Air Quality In Schools Research Articles

Indoor air quality differences between urban and rural preschools in Korea

Preschool indoor air quality (IAQ) is believed to be different from elementary school or higher school IAQ and preschool is the first place for social activity. Younger children are more susceptible than higher-grade children and spend more time indoors. The purpose of this study was to compare the indoor air quality by investigating the concentrations of airborne particulates and gaseous materials at preschools in urban and rural locations in Korea. We investigated the concentrations of airborne particulates and gaseous materials in 71 classrooms at 17 Korean preschools. For comparison, outdoor air was sampled simultaneously with indoor air samples. Airborne concentrations of total suspended particulates, respirable particulates, lead, asbestos, total volatile organic compounds and components, formaldehyde, and CO(2) were measured with National Institute for Occupational Safety and Health and/or Environmental Protection Agency analytical methods. The concentration profiles of the investigated pollutants in indoor and urban settings were higher than those in outdoor and rural areas, respectively. The ratios of indoor/outdoor concentrations (I/O) of particulates and gaseous pollutants were characterized in urban and rural preschools. Total dust concentration was highest in urban indoor settings followed by urban outdoor, rural indoor, and rural outdoor locations with an I/O ratio of 1.37 in urban and 1.35 in rural areas. Although I/O ratios of lead were close to 1, lead concentrations were much higher in urban than in rural areas. The I/O ratio of total VOCs was 2.29 in urban and 2.52 in rural areas, with the highest level in urban indoor settings. The I/O ratio of formaldehyde concentrations was higher in rural than in urban areas because the outdoor rural level was much lower than the urban concentration. Since an I/O ratio higher than 1 implies the presence of indoor sources, we concluded that there are many indoor sources in preschools. We confirmed that pollutants in indoor and urban settings were higher than those in outdoor and rural areas, respectively. Preschool children are expected to spend more time inside preschool facilities and therefore to be more exposed to pollutants. As far as we know, preschool IAQ is different from elementary school or higher school IAQ. Also, they are more vulnerable than higher-grade children. We found that the indoor and urban concentration profiles of the studied pollutants in preschools were higher than those in outdoor and rural areas. We believe that our findings may be useful for understanding the potential health effects of exposure and intervention studies in preschools.

Biomonitoring of indoor air genotoxic properties in ten schools using Scindapsus aureus

School is the most important indoor environment for children besides their home. Indoor air quality in school is a critical parameter that needs to be considered for children's health. Atmospheric measurements provide concentrations of pollutants which are used for risk assessments. However, those data are limited to study complex interactions between pollutants, and the genotoxic potential of air pollution is still often misunderstood. The aim of this study was to assess the genotoxic potential of indoor air pollutants in ten schools in France. For this purpose, we have used the comet assay in Scindapsus aureus (pothos) which is a very common indoor plant. For all classrooms, data obtained with exposed plants were significantly higher than those obtained with control. This study shows that plants can be used in indoor environments as well as outdoor for air monitoring, and can participate in health risk assessment.

Indoor Air Quality Assessment of Elementary Schools in Curitiba, Brazil

The promotion of good indoor air quality in schools is of particular public concern for two main reasons: (1) school-age children spend at least 30% of their time inside classrooms and (2) indoor air quality in urban areas is substantially influenced by the outdoor pollutants, exposing tenants to potentially toxic substances. Two schools in Curitiba, Brazil, were selected to characterize the gaseous compounds indoor and outdoor of the classrooms. The concentrations of benzene, toluene, ethylbenzene, and the isomers xylenes (BTEX); NO2; SO2; O3; acetic acid (HAc); and formic acid (HFor) were assessed using passive diffusion tubes. BTEX were analyzed by gas chromatography–ion trap mass spectrometry and other collected gasses by ion chromatography. The concentration of NO2 varied between 9.5 and 23 µg m−3, whereas SO2 showed an interval from 0.1 to 4.8 µg m−3. Within the schools, BTEX concentrations were predominant. Formic and acetic acids inside the classrooms revealed intermediate concentrations of 1.5 µg m−3 and 1.2 µg m−3, respectively.

학교 실내공기질 및 건강 영향

Indoor air quality at classrooms is of special concern since students are susceptible and indoor air problems can be so subtle that it does not always produce easily recognizable health effects. The main objectives of the study were to investigate the time-activity pattern of school students, to determine the sources of poor indoor air quality in schools, and to demonstrate how indoor air quality in schools causes adverse health effects such as headache, upper airway irritation, fatigue, and lethargy. Recent articles ranging from 1987-2009 related to school indoor air quality were systematically reviewed. Building-associated health effects can increase student absences from school and degrade the performance of children while in school. The reduced ventilation rate was associated with a decreased ability to concentrate along with increased adverse health symptoms. There was an association between residential proximity to busy roads and a variety of adverse respiratory health outcomes in children. Consequently, the current findings suggest the need for control strategy for school indoor air pollutants with multidisciplinary approach methods because Korea has no other natural resources except manpower especially.

A methodology for post-occupancy evaluation of ventilation rates in schools

The importance of maintaining adequate indoor air quality in schools is recognised as a contributing factor to pupils' learning performance. This paper describes a series of field measurements that investigating the ventilation rates in four recently built secondary schools in England. All schools were assessed for compliance with the recently adopted Building Bulletin 101, which defines the set of criteria in relation to the ventilation rates and indoor air quality in new school buildings. Using the obtained results a methodology has been suggested for post-occupancy evaluation of ventilation rates in schools. The suggested methodology draws particular attention to the dynamic nature of the interaction between the building and their occupants. Practical application: The new Building Bulletin 101 is quoted in Approved Document F as a means of compliance with Building Regulations for school buildings in the UK. This paper, based on four case studies, highlights some of the problems facing architects, mechanical engineers and building control officers associated with post-occupancy evaluation of ventilation rates in new school buildings. The methodology suggested in this paper, which differs radically from the current practice, takes into account the changing nature of the indoor environment in schools including occupancy level and occupant behaviour.

Indoor Air Quality in Schools and Health Symptoms among Portuguese Teachers

ABSTRACT The purpose of this study was: (i) to characterize the school indoor environment; (ii) to evaluate self-reported prevalence of disease symptoms among Portuguese teachers; and (iii) to evaluate, as far as we know for the first time in Portugal, the impact of the indoor air quality of schools on the prevalence of disease symptoms among teachers. The study was performed in the city of Oporto, starting in 2004; it included the analysis of questionnaires fulfilled by schoolteachers (n = 177), walkthrough surveys of schools grounds, buildings, and individual classrooms (n = 76), as well as indoor air monitoring. Respirable particle increase was related to chalk use and CO2 concentrations widely exceeded reference values. Schools located near traffic lines presented higher benzene and toluene concentrations. The guideline for total viable microorganism concentration was exceeded in 35.6% of classrooms. Significant increases in disease symptoms among teachers could be related to poor indoor air quality, which was mainly due to inefficient ventilation and influence of traffic emissions. Statistically significant correlations were found between central nervous system injuries and the levels of CO2 and total volatile organic compounds, and between upper respiratory problems and mucosal irritation and the levels of TVOC and respirable particles.

Feinstaubbelastung in Schulen - Untersuchungsergebnisse und Lösungsansätze am Beispiel der Stadt Frankfurt am Main

Indoor air quality in schools, especially the levels of particulate matter in classrooms, have become a matter of great public concern in Germany, Convenient recommendations to improve the hygienic situation in classrooms via cleaning and ventilation are often not followed. Here, data on particulate matter in the indoor air of classrooms, before and after intensified cleaning, are reported. In the winter of 2006, analyses for particulate matter were done in two primary schools in Frankfurt/M, one of them located in a rural area the other one in an inner city area of Frankfurt/M. Particulate matter (PM10) was analysed by laser beam technology, the data documented every five minutes from 8 am to 2 pm. In parallel, a documentation of the number of persons present in the room, their activity and ventilation was done according to a standardised protocol. Measurements were collected for a period of three weeks. During the first week, the normal school situation was analysed, i.e., the classrooms were ventilated as usual and were cleaned by wet wiping twice a week. During the second and third weeks, the rooms were cleaned every day, so that the effect of intensified cleaning could be studied. In winter 2007, these measurements were continued for one week in two classrooms of a passive house school, following the identical study protocol. During the first week--wet cleaning twice a week--mean particulate concentrations of 86 microg/m3 (median 60 microg/m3) were obtained, during the 2nd and 3rd weeks--wet cleaning every school day mean concentrations of 60 microg/m3 (median 53 microg/m3)--with great differences on different days. Especially during and after handicraft (casting candles) lessons, maximum levels up to >1000 microg/m3 were analysed. Although an impact of cleaning on levels of indoor particles could be established, indoor PM10 levels were dominated by indoor factors, such as occupancy and activity of the persons in the room. After substraction of the outdoor PM10 levels from the indoor levels, the "indoor part" was ca. 50 microg/m3 before, and ca. 30 microg/m3 during intensified cleaning. Further detailed investigations showed the predominance of particles >1 microm indoors, which could easily be diminished by cleaning and ventilation. Indoor particles <0.5 microm, however, were increased via ventilation. In classrooms, generally higher indoor levels of air particulate matter are detected than outdoors. Particulate matter in the indoor air of classrooms is to be considered as an indicator of low hygiene and of increased and avoidable heath risk for pupils and teachers. Our data indicate the relevance of cleaning--and with regard to PM <1 microm also of ventilation--for the reduction of particulate matter in classrooms. Therefore, these measures should be taken to improve indoor air quality in schools.

Asthma Prevalence, Management, and Education in New York State Elementary Schools: A Survey of School Nurses

A survey of school nurses was conducted in New York State elementary schools to assess asthma and asthma management in students. The survey contained questions about asthma morbidity, management and education, obstacles to management, and school indoor air quality. The reported prevalence of asthma among students was 8.5%. Of the students with asthma, 64% visited the health office, 26% were absent from school, 20% had physical limitations, and 7% needed urgent care. Only 28% had a written management plan at school, less than 25% of schools used asthma self-management programs, and obstacles to management included lack of time and funding. More than 25% rated school indoor air quality as "fair" or "poor." Schools need to adopt key components of asthma management, and school nurses should be encouraged to work with others in the school setting to address indoor air quality problems that might be affecting health.

Comparative overview of indoor air quality in Antwerp, Belgium

This comprehensive study, a first in Belgium, aimed at characterizing the residential and school indoor air quality of subgroups that took part in the European Community Respiratory Health Survey and the International Study of Asthma and Allergy in Childhood [Masoli M, Fabian D, Holt S, Beasley R. Global Burden of Asthma, Medical Research Institute of New Zealand, University of Southampton; 2004.] questionnaire-based asthma and related illnesses studies. The principal aim was to perform a base-line study to assess the indoor air quality in Antwerp in terms of various gaseous and particulate pollutants. Secondly, it aimed to establish correlations between these pollutants investigated, the pollutant levels in the indoor and outdoor micro-environments, findings of the previous questionnaire-based studies and an epidemiological study which ran in conjunction with this study. Lastly, these results were compared and evaluated with current indoor and ambient guidelines in various countries This paper presents selected results on PM1, PM2.5 and PM10 mass concentrations and elemental C estimates as black smoke, as well as gaseous NO 2, SO 2, O 3 and BTEX concentrations of 18 residences and 27 schools. These are related to current guidelines of Flanders, Germany, Norway, China and Canada and evaluated with reference to selected similar studies. It was found that indoor sources such as tobacco smoking and carpets, the latter causing re-suspension of dust, are responsible for elevated indoor respirable particulate matter and place school children and residents at risk. Both PM2.5 and PM10 equalled or exceeded the current guidelines adopted by Flanders, noting that 12-h and 24-h PM2.5 were compared with an annual limit value. Indoor and ambient NO 2 concentrations in the school campaign were higher than the annual EU ambient norm. The other studied pollutant levels were below the current guidelines.

Particulate matter in the indoor air of classrooms—exploratory results from Munich and surrounding area

Numerous epidemiological studies have demonstrated the association between particle mass (PM) concentration in outside air and the occurrence of health related problems and/or diseases. However, much less is known about indoor PM concentrations and associated health risks. In particular, data are needed on air quality in schools, since children are assumed to be more vulnerable to health hazards and spend a large part of their time in classrooms. On this background, we evaluated indoor air quality in 64 schools in the city of Munich and a neighbouring district outside the city boundary. In winter 2004–2005 in 92 classrooms, and in summer 2005 in 75 classrooms, data on indoor air climate parameters (temperature, relative humidity), carbon dioxide (CO 2) and various dust particle fractions (PM 10, PM 2.5) were collected; for the latter both gravimetrical and continuous measurements by laser aerosol spectrometer (LAS) were implemented. In the summer period, the particle number concentration (PNC), was determined using a scanning mobility particle sizer (SMPS). Additionally, data on room and building characteristics were collected by use of a standardized form. Only data collected during teaching hours were considered in analysis. For continuously measured parameters the daily median was used to describe the exposure level in a classroom. The median indoor CO 2 concentration in a classroom was 1603 ppm in winter and 405 ppm in summer. With LAS in winter, median PM concentrations of 19.8 μg m −3 (PM 2.5) and 91.5 μg m −3 (PM 10) were observed, in summer PM concentrations were significantly reduced (median PM 2.5=12.7 μg m −3, median PM 10=64.9 μg m −3). PM 2.5 concentrations determined by the gravimetric method were in general higher (median in winter: 36.7 μg m −3, median in summer: 20.2 μg m −3) but correlated strongly with the LAS-measured results. In explorative analysis, we identified a significant increase of LAS-measured PM 2.5 by 1.7 μg m −3 per increase in humidity by 10%, by 0.5 μg m −3 per increase in CO 2 indoor concentration by 100 ppm, and a decrease by 2.8 μg m −3 in 5–7th grade classes and by 7.3 μg m −3 in class 8–11 compared to 1–4th class. During the winter period, the associations were stronger regarding class level, reverse regarding humidity (a decrease by 6.4 μg m −3 per increase in 10% humidity) and absent regarding CO 2 indoor concentration. The median PNC measured in 36 classrooms ranged between 2622 and 12,145 particles cm −3 (median: 5660 particles cm −3). The results clearly show that exposure to particulate matter in school is high. The increased PM concentrations in winter and their correlation with high CO 2 concentrations indicate that inadequate ventilation plays a major role in the establishment of poor indoor air quality. Additionally, the increased PM concentration in low level classes and in rooms with high number of pupils suggest that the physical activity of pupils, which is assumed to be more pronounced in younger children, contributes to a constant process of resuspension of sedimented particles. Further investigations are necessary to increase knowledge on predictors of PM concentration, to assess the toxic potential of indoor particles and to develop and test strategies how to ensure improved indoor air quality in schools.

Statistical analysis of parameters influencing the relationship between outdoor and indoor air quality in schools

Under the French national research program PRIMEQUAL, measurements of outdoor and indoor pollution have been performed in eight school buildings in La Rochelle (France) and its suburbs. The school buildings were either naturally ventilated by opening the windows or mechanically ventilated with minimum fresh air, and demonstrated various permeabilities. Ozone, nitrogen oxides (NO and NO2), and particulate matter (PM) (15 size intervals ranging from 0.3 to 20 μm) concentrations were monitored continuously indoors and outdoors for two 2-week periods. The indoor relative humidity, temperature, CO2 concentration (room occupancy), window openings and permeability of the building were also measured. Principal component analysis (PCA), a multivariate observation-based statistical method, was used to determine the parameters influencing the relationship between the outdoor and indoor concentration levels. After a brief description of the experimental data and methodology, the paper presents a detailed analysis of the PCA diagrams. This analysis leads to distinguish between positively correlated, negatively correlated and non-correlated variables. The main conclusions arising from the study are: (1) the influence of the room occupancy on the particle concentrations indoors changes with different particle sizes, (2) the building air-tightness and the outdoor concentration level greatly influence the indoor/outdoor (I/O) concentration ratios of ozone, and (3) indoor ozone and particles concentrations are negatively correlated, which may be the result of complex homogeneous and/or heterogeneous processes.

Perceptions of indoor air quality associated with ventilation system types in elementary schools.

With the increased utilization of school buildings on a year-round basis, school indoor air quality has become a national concern. The purpose of this study was to evaluate possible associations between ventilation system type and occupant perception of indoor air quality. Staff (n = 403) from 12 schools completed a self-administered questionnaire. Carbon dioxide (CO2) levels, air exchange rates, and particle counts were also measured for each school. Schools with unit ventilator (UV) systems had the lowest mean CO2 level at 637 ppm, followed by the variable air volume (VAV) systems with 664 ppm, and constant volume (CV) systems with a mean of 703 ppm. Schools with UV systems had the lowest mean air exchange rate at 2.67 air changes per hour (ACH), followed by the VAV system type at 2.80 ACH and the CV system type at 4.61 ACH. Indoor versus outdoor particle ratios were calculated for each ventilation system type. Particles with aerodynamic diameters ranging from 0.1-1.0 microm had a geometric mean ratio ranging from 0.38 to 0.68; particles with aerodynamic diameters ranging from 1-3 microm had ratios ranging from 1.39 to 5.47, and particles with aerodynamic diameters greater than 3 microm had ratios ranging from 3.20 to 14.76. Schools using VAV systems had a significantly lower prevalence of red and watery eyes while schools with UV systems had an elevated prevalence of nasal congestion, sore throat, headache, and dustiness complaints. This increased prevalence of complaints in buildings with UV systems may be due to the increased particulate levels.

Indoor air pollutants in schools: nasal patency and biomarkers in nasal lavage.

There is growing concern about the respiratory health aspects of the indoor air quality in schools. A standardized investigation, including nasal lavage (NAL), measurement of the nasal cavity by acoustic rhinometry, and hygienic measurements of airborne pollutants, was performed in classrooms, outside the pollen season. All 279 school personnel working in the main buildings of 12 randomly selected primary schools in an urban community in central Sweden (Uppsala) were invited to enroll in the study; 234 (84%) participated. Eosinophil cationic protein (ECP), myeloperoxidase (MPO), lysozyme, and albumin were analyzed in NAL fluid. Crude statistical analysis, as well as multiple regression analysis, was performed, controlling for room temperature, age, sex, current smoking, and a history of atopy. Most classrooms (83%) did not meet the Swedish ventilation standards. A lower degree of nasal patency was found at higher concentrations of respirable dust, nitrogen dioxide (NO2), formaldehyde, and total molds, and in the presence of Aspergillus spp. in the classroom air. The most consistent findings were observed for formaldehyde, NO2, and Aspergillus spp., related to both decreased nasal patency and increase of ECP and lysozyme in NAL. The presence of yeast was associated with an increase of ECP and lysozyme in NAL, but was not related to nasal patency. Ventilation flow was below current hygienic standards in the classrooms. Air pollutants in the classroom air may influence nasal patency and inflammatory response in the nasal mucosa.

Indoor air quality in a middle school, Part I: Use of CO2 as a tracer for effective ventilation.

The overall objective of the study was to evaluate the indoor air quality at a middle school with an emphasis on characterizing baseline conditions. The focus of this article is on the relationship between occupancy and measured concentrations of carbon dioxide, and an evaluation of the use of carbon dioxide as a tracer for ventilation in the school. The school was characterized as having no health complaints, good maintenance schedules, no carpeting within the classrooms or hallways, and no significant remodeling, and its officials had agreed to allow the sampling to take place during school hours. Monitoring followed the guidelines recommended in the "Preliminary Draft: Conceptual Standardized EPA Protocol For Characterizing Indoor Air Quality in School Buildings." Four indoor locations including the cafeteria, a science classroom, an art classroom, and the lobby outside the main office, and one outdoor location were sampled for various environmental comfort and pollutant parameters for one week in February 1997. A consistent relationship between hourly occupancy and corresponding carbon dioxide concentrations was seen. Carbon dioxide concentrations in the cafeteria, art room, and lobby were within specified American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) guidelines for comfort (< 1000 ppm). The science room had the highest concentrations (frequently exceeding 1000 ppm) due to high occupancy and non-functioning unit ventilators. Measured ventilation rates were within specified ASHRAE guidelines for the art room, cafeteria, and lobby. The science room, which relied on natural ventilation only, was not able to meet the ASHRAE guideline on one of the three days studied. The use of a completely mixed space, one compartment mass balance model with estimated CO2 generation rates and measured CO2 concentrations is shown to be a useful method for evaluating ventilation. Modeled effective ventilation, air changes per hour, and mixing factors reflected measured carbon dioxide concentrations and measured ventilation in each room. Mechanical ventilation afforded better mixing than natural ventilation. This study demonstrates the usefulness of collecting indoor CO2 and occupancy data when carrying out indoor air quality evaluations in schools.

Subjective Indoor Air Quality in Schools in Relation to Exposure

This paper presents data on indoor air quality in schools as perceived by those working in them and relates these data to exposure measurements. Data on subjective air quality, domestic exposures and health aspects were gathered by means of a questionnaire which was sent to all personnel in 38 schools; it was completed by 1410 persons (85’4 of the total). Data on exposure were gathered by exposure measurements in classrooms. The results indicate that 53% of the personnel perceived the indoor air quality as bad or very bad. It was perceived as worse by those who were younger, those who were dissatisfied with their psychosocial work climate and those who were not exposed to tobacco smoke at home. In older school buildings and buildings with displacement ventilation there was less dissatisfaction with the air quality. There were no significant relations between complaints and air exchange rate or concentration of carbon dioxide. The air quality was perceived as worse at higher levels of exposure to a number of airborne compounds including volatile organic compounds, moulds, bacteria and respirable dust. It was concluded that exposure to indoor pollutants affects perception even at the low concentrations normally found indoors in nonindustrial buildings.

Subjective Indoor Air Quality in Schools - The Influence of High Room Temperature, Carpeting, Fleecy Wall Materials and Volatile Organic Compounds (VOC)

There is a growing concern about indoor air quality (IAQ) in schools. We have studied relations between subjective indoor air quality (SIAQ) and measured IAQ among school personnel (N = 97) in six mid-Swedish primary schools. Information on SIAQ and the psychosocial work environment was measured by a self-administered questionnaire, using analogue rating scales. Indoor exposures were quantified by hygienic measurements. Perception of high room temperature was related to a poor climate of cooperation, fleecy wall materials, and the concentration of volatile organic compounds (VOC), including xylene, limonene, and butanols. Perception of air dry-ness was related to atopy, work stress, poor climate of cooperation, high room temperature, low air humidity, and high VOC concentration, including, limonene, and n-alkanes. Perception of dusty air was related to work stress, the role of schoolteacher, and exposure to 2-ethyl-1-hexanol. No relations were found between SIAQ and CO2, building age, or respirable dust. To achieve a good SIAQ, room temperature should be kept at a maximum of 22°C, and exposure to VOCs and fleecy materials should be minimized. Finally, a sound psychosocial work climate is essential for the perception of a good physical indoor climate.

Indoor air quality in schools: exposure to fungal allergens

This study examined indoor air quality within schools in Kansas City, Spokane, Santa Fe, and Orlando. Air sampling was undertaken with both Andersen Single Stage Samplers and Burkard Personal Air Samplers. The data show a wide range of indoor exposures ranging from less than 100 colony forming units (CFU/m3) for viable fungi and 100 spores/m3 for total spores in Spokane and Santa Fe to concentrations over 6000 CFU/m3 for viable fungi and 15 000 spores/m3 for total fungi in Orlando and Kansas City, respectively. In the majority of sites the indoor airspora reflected the outdoor taxa withCladosporium the most abundant genus identified; however, several indoor locations had elevated levels ofPenicillium andAspergillus indicating possible sources of indoor contamination. Airborne basidiospores and smut spores were also fairly abundant in the schools and were among the top five taxa identified. The data also indicated that the airborne concentrations vary significantly during the day and between classrooms within each school. Continued studies in schools are needed to fully assess both the exposure levels and the clinical significance to atopic children allergic to these spores.