Indoor School Environment Research Articles

Predictors of indoor absolute humidity and estimated effects on influenza virus survival in grade schools

BackgroundLow absolute humidity (AH) has been associated with increased influenza virus survival and transmissibility and the onset of seasonal influenza outbreaks. Humidification of indoor environments may mitigate viral transmission and may be an important control strategy, particularly in schools where viral transmission is common and contributes to the spread of influenza in communities. However, the variability and predictors of AH in the indoor school environment and the feasibility of classroom humidification to levels that could decrease viral survival have not been studied.MethodsAutomated sensors were used to measure temperature, humidity and CO2 levels in two Minnesota grade schools without central humidification during two successive winters. Outdoor AH measurements were derived from the North American Land Data Assimilation System. Variability in indoor AH within classrooms, between classrooms in the same school, and between schools was assessed using concordance correlation coefficients (CCC). Predictors of indoor AH were examined using time-series Auto-Regressive Conditional Heteroskedasticity models. Classroom humidifiers were used when school was not in session to assess the feasibility of increasing indoor AH to levels associated with decreased influenza virus survival, as projected from previously published animal experiments.ResultsAH varied little within classrooms (CCC >0.90) but was more variable between classrooms in the same school (CCC 0.81 for School 1, 0.88 for School 2) and between schools (CCC 0.81). Indoor AH varied widely during the winter (range 2.60 to 10.34 millibars [mb]) and was strongly associated with changes in outdoor AH (p < 0.001). Changes in indoor AH on school weekdays were strongly associated with CO2 levels (p < 0.001). Over 4 hours, classroom humidifiers increased indoor AH by 4 mb, an increase sufficient to decrease projected 1-hour virus survival by an absolute value of 30% during winter months.ConclusionsDuring winter, indoor AH in non-humidified grade schools varies substantially and often to levels that are very low. Indoor results are predicted by outdoor AH over a season and CO2 levels (which likely reflects human activity) during individual school days. Classroom humidification may be a feasible approach to increase indoor AH to levels that may decrease influenza virus survival and transmission.

Indoor and outdoor characterisation of organic and inorganic compounds in city centre and suburban elementary schools of Aveiro, Portugal

Pollutants inside school buildings may affect children's health and influence learning performance and attendance. This study investigated pollutant concentrations inside and outside school buildings at different locations (city centre and suburban) in Aveiro, Portugal, between April and June 2010. The aim was to evaluate simultaneously comfort parameters (temperature, relative humidity, CO2 and CO) and indoor and outdoor concentrations of VOCs, NO2, PM10 and bioaerosols. PM10 samples were analysed and characterised, for the first time, for the water soluble inorganic ions (WSII), organic carbon (OC), elemental carbon (EC), carbonates, and detailed organic speciation. The CO2 and bioaerosol levels were higher than the acceptable maximum values to the occupants' comfort. Concentrations of the traffic tracer NO2 were higher outdoors. The daily indoor PM10 levels were always higher than those outdoors, except on weekends, suggesting that the physical activity of pupils and class works highly contributed to the emission and resuspension of particles. Almost all identified VOCs showed I/O ratios higher than one, which denotes an important contribution from indoor sources at both schools. The suburban school was more exposed to industrial emissions than the institution located in the city centre. Especially at the city centre, infiltration of outdoor particulates leads to contamination of school indoor environment with vehicle emissions and biomass burning smoke likely coming from biofuel use in nearby restaurants and bakeries.

Indoor school environment: easy and low cost to assess inorganic pollutants

Total particulate matter (TPM) was passively collected inside two classrooms of each of five elementary schools in Lisbon, Portugal. TPM was collected in polycarbonate filters with a 47 mm diameter, placed inside of uncovered plastic petri dishes. The sampling period was from 19 May to 22 June 2009 (35 days exposure) and the collected TPM masses varied between 0.2 mg and 0.8 mg. The major elements were Ca, Fe, Na, K, and Zn at μg level, while others were at ng level. Pearson′s correlation coefficients above 0.75 (a high degree of correlation) were found between several elements. Soil-related, traffic soil re-suspension and anthropogenic emission sources could be identified. Blackboard chalk was also identified through Ca large presence. Some of the determined chemical elements are potential carcinogenic. Quality control of the results showed good agreement as confirmed by the application of u-score test.

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.

An update on sick building syndrome

The aim is to describe recent insight into risk factors for symptoms included in the sick building syndrome (SBS) and to give an insight into preventive work to reduce SBS. New studies have added evidence for the role of personality traits and psychosocial work environment, reactive chemistry and the inflammatory properties of indoor particles for SBS. Field studies using physiological methods and measurements of oxidative stress can lead to better understanding of the cause of SBS. Moreover, there is an increased focus on the indoor environment and 'sick house syndrome' in Asia. SBS is related to both personal and environmental risk factors. In the office environment, SBS may have important economical implications. More focus is needed on the indoor environment in schools and day care centres, hospitals and nursing homes for elderly. Improvements of the home environment may be the most cost-effective way to reduce the burden of indoor exposure. The link between indoor and outdoor air pollution should not be neglected, and the role of energy saving and climate changes will be an important future issue.

Evaluating Indoor Environmental Quality of Public School Buildings in Jordan

This paper aimed to investigate the indoor environments of schools in Jordan. It considers the availability of public safety conditions and conformity of school's environmental conditions to standards, and also aimed to obtain baseline data about environments in schools that could help decision makers in their efforts to improve the school environment. Indoor environmental quality is an integral part of the entire building performance that encompasses several environmental parameters such as air quality, air temperature, relative humidity, and acoustics. Creation of a successful indoor environment is dependent on an understanding of the environmental factors that include building design and setting. A cross multiple design strategy was adopted that included objective measurements (building physical measurements, monitoring, and archival data) and subjective measurements that included (questionnaires, interviews, and student's medical records). Seventeen schools were selected based on a multi-stage systematic sampling strategy. The sample size was sufficient to be representative of the entire school building stock in the country. The school-building design was adapted to the prototype systems that were duplicated in different locations in Jordan. The findings indicated that there were significant differences among building prototypes and across the locations of the schools. Site selection and planning were found to play a significant role in improving indoor environment quality. Building design should take the environmental factors into consideration from the early stages of design and construction. Overall these strategies depend on adapting passive design techniques that can improve energy efficiency and enhance occupant comfort and satisfaction.

충남 지역 일부 학교의 PM10과 중금속 농도에 관한 연구

In this study, in order to analyze the air quality of the indoor environments of schools, we measured the indoor, outdoor and personal exposure concentration level of <TEX>$PM_{10}$</TEX> for 40 classrooms(20 old, 20 new) in chungnam area from June 22 to July 19 and from November 21 to December 30, 2003. 1. Old classrooms contained more dust than new classrooms; the average of respirable dust is <TEX>$43.27\;{\mu}g/m^3$</TEX> for new classrooms while <TEX>$53.38\;{\mu}g/m^3$</TEX> for old one. The exposure concentration level of respirable dust in new classrooms were in summer higher outdoors than indoors. The values were indoors <TEX>$46.71\;{\mu}g/m^3$</TEX>, outdoors <TEX>$50.46\;{\mu}g/m^3$</TEX>, and personal <TEX>$41.62\;{\mu}g/m^3$</TEX>. Meanwhile in winter indoors had a higher concentration level than outdoors, the values being indoors <TEX>$39.11\;{\mu}g/m^3$</TEX>, outdoors <TEX>$34.86\;{\mu}g/m^3$</TEX>, and personal <TEX>$49.01\;{\mu}g/m^3$</TEX>. 2. Cr concentration level within dust was slightly higher in summer indoors (<TEX>$101.50{\pm}32.10\;ng/m^3$</TEX>) and outdoors (<TEX>$100.89{\pm}35.18\;ng/m^3$</TEX>) than winter indoors (<TEX>$85.80{\pm}48.95\;ng/m^3$</TEX>) and outdoors (<TEX>$74.43{\pm}38.93\;ng/m^3$</TEX>), but in personal concentration level, winter was higher. The results of this research show insufficient understanding of health risks from indoor air pollution, and shows possible health problems to students from school indoor air pollution. As such, a logical and systematic education program for students about the importance of indoor air quality should be carried out. Also the results of <TEX>$PM_{10}$</TEX> concentration level measurements emphasize the need for regular measurements of indoor / outdoor and personal concentration level. New classrooms in particular needs to be used after measuring pollutants and safety, and requires installation of a ventilation device in all classrooms to improve air quality.

Sick Buildings or Not: Indoor Air Quality and Health Problems in Schools

Poor indoor air in schools has become a wide-spread problem with serious effects on occupant health. Resultant costs can be considerable at both local and national government levels. These include absenteeism and rehabilitation as well as building alterations and even demolition and rebuilding. This project aims to show factors contributing to health problems in Swedish schools. It includes a literature survey and particle measurements taken during various activities. Due to the fact that today there is no standard for indoor air quality (IAQ) in schools, in this project we used the outdoor air surrounding the building as an indicator. Results showed that indoor school environments had high airborne pollution levels, to a degree that probably causes health problems for many people. Regarding IAQ, this project shows the importance of taking into consideration choices in activities and furnishing of the building.

Indoor environment and pupils' health in primary schools

Dutch children are legally bound to spend 15% of their time in a school setting. The indoor environment in Dutch primary schools is known to be substandard. However, it is unclear to what extent the health of pupils is affected by the indoor school environment. The paper aims to assess the associations between indoor environmental quality in Dutch schools and pupils' health, also taking into account the children's home environment and personal factors. A cross-sectional study was performed in 11 classrooms in 11 different schools in the Netherlands. The study included exposure measurements, building inspections, and a questionnaire survey on pupils' health and domestic exposure. Principal Component Analysis (PCA) and non-parametric tests were performed to assess relationships. None of the schools complied with all indoor environmental quality standards. The importance of both the school and the domestic environment to pupils' health is shown in a multivariate analysis. If both the school and the home environment are highly polluted, improving conditions at school alone may not result in improved health of the children. Aux Pays-Bas, la loi oblige les enfants à passer 15% de leur temps dans un environnement scolaire. On sait que l'intérieur des écoles primaires hollandaises est sub-standard. En revanche, on ne sait pas précisément dans quelle mesure la santé des élèves est affectée par leur environnement scolaire intérieur. L'objectif de cet article est d'évaluer les relations qui existent entre la qualité de l'environnement intérieur des écoles hollandaises et la santé des élèves, en tenant compte également de l'environnement du foyer de ces enfants et de facteurs personnels. Une analyse en coupe a été exécutée dans 11 salles de classe de 11 écoles différentes des Pays-Bas. Cette étude englobait les mesures d'exposition, des inspections des bâtiments et un questionnaire sur la santé des élèves et leur exposition aux conditions domestiques. Pour évaluer ces relations, on a procédé à une analyse en composantes principales (ACP) et à des tests non-paramétriques. Aucune de ces écoles ne répondait aux normes de qualité environnementale intérieure. L'importance de l'environnement scolaire et domestique sur la santé des élèves est illustrée dans une analyse à variables multiples. Si l'environnement scolaire et l'environnement à la maison sont tous les deux très pollués, la seule amélioration des conditions dans les écoles risque de ne pas se traduire par une amélioration de la santé des élèves. Mots-clés: caractéristiques des bâtiments, parc bâti, santé, qualité de l'air intérieur, analyse par composantes principales (APC), écoles

Creation of healthy indoor environment in schools, ISIAQ Task Force on schools -A Nordic approach, International Society for Indoor Air Quality and Climate, ISIAQ会員7Euro、非会員11Euro, A4判44ページ

Creation of healthy indoor environment in schools, ISIAQ Task Force on schools -A Nordic approach, International Society for Indoor Air Quality and Climate, ISIAQ会員7Euro、非会員11Euro, A4判44ページ