Impact of ozone on indoor air quality: a preliminary field study

The purpose of this paper is to document the potential impact on indoor air quality of outdoorozone during photochemical pollution episodes. A preliminary one-day experiment wasconducted during summer 2002 in a room of the CSTB experimental house MARIA. Ozone,VOC and aldehyde concentrations were monitored outdoors and indoors from 8 a.m. to 8 p.m.Outdoor ozone hourly mean concentrations increased from 30 to 100 g/m3 during the day.The indoor to outdoor ratio ranged from 0.10 to 0.25, indicating possible ozone-inducedreactions occurring indoors.

A pilot study on VOCs and carbonyl compounds in Chinese residences

The concentrations of volatile organic compounds (VOCs) and carbonyl compounds were measuredat 40 residences in three cities of China (30 from Chengdu, five each from Changsha and Beijing).Indoor, outdoor and personal exposure samples were simultaneously collected at each site. The average concentrations of benzene, toluene, xylene, especially benzene, were significantly higher than those of other countries both indoor and outdoor. There is significant correlation between indoor concentration and personal exposure of VOCs and carbonyl compounds.

Aldehydes and VOCs in newly-built unoccupied houses in Tokyo

The Ministry of Health, Labor and Welfare in Japan have published the guideline values for14 chemical compounds including formaldehyde, toluene, xylenes etc., in order to solve theSick house syndrome problem. In this study, field measurements on indoor air quality wereconducted in newly-built houses which had not been occupied.The concentrations of aldehydes and VOCs, the ventilation rate, the emission rate offormaldehyde from each surface material, temperature and humidity were measured in threehouses in summer and in two houses in winter.

Measurements of indoor concentrations of aldehydes, VOCs and fungi in newly built apartment houses in Tokyo

The purpose of this study is to identify the causality explaining indoor concentrations offormaldehyde, VOCs and fungi which have significant health effects. In the rainy season(July), summer (August), autumn (October) and winter (December), measurements werecarried out in three newly built apartment complexes. In each complex the same buildingmaterials were used.

The application of semiconductor-based odour sensors capable of measuring and evaluating indoor air quality

Now believed to be responsible for anaphylaxis to chemical substances, concentrations of formaldehyde and VOCs emitted by interior finish materials and furniture, is very low in residential spaces. To accurately measure these concentrations, it is necessary to concentrate the air sample during sampling and to employ high-precision analysers such as a GC analyzer to obtain the results. Since these complicated sampling and analytical operations require a high level of expertise, the development of an on-the-spot precise measuring instrument has long been awaited.

Ventilation in dutch houses, a study in a representative sample of the dutch housing stock

The goal of this study was the determination of the existing situation in houses with regard to air quality and energy used for ventilation in relation to the health of inhabitants. For the energy policy the Government is considering increased energy requirements for dwellings. They are permanently opposed in doing so by people who are concerned about negative health effect due to increased requirements on for instance air tightness of buildings. To have at least a reference point, they are interested in the existing situation.

A first study of natural and hybrid ventilation systems in the urban environment

An experimental campaign was organized during the summer period 2002 in Athens, in the framework of the European RESHYVENT Project. The main purpose was to indicate the impact of the urban environment on the natural and hybrid ventilation air flow process in urban canyons. Field and indoor experimental procedures were carried out in two urban canyons, presenting different geometric and urban features. The experiments were organized for more than three consecutive days within three different periods in summer and on a 24-hour basis.

Computational and experimental reduced-scale modelling of air conditioned rooms

An improper air distribution within air-conditioned rooms is one of the largest causes of inadequate indoor air quality and thermal comfort. A good knowledge of the phenomena allows for the advance of eventual deficiencies, thus becoming a powerful tool for the optimization of new projects or for the improvement of the operation conditions of the projects already implemented. In this study two methods were applied, one computational and the other experimental, for modelling of non-isothermal turbulent flows in airconditioned rooms. The computational model consists of a numerical

Experimental and CFD studies on surface condensation

Condensation and mold problems have been identified as one of the severest IAQ problems in Japan. Especially in the wintertime, moisture condenses on cold wall surfaces where it can cause deterioration of the building materials and mold growth related to allergic symptoms. This paper discusses the possibility of using the CFD method to solve condensation problems.
Firstly, a CFD model for simulating condensation is developed, and then the validity of this model is examined experimentally.

An investigation of air inlet in simulating the dispersion of indoor contaminants via computational fluid dynamics

The aim of the study is to validate CFD approaches for the simulation of the dispersion of gases and vapors in an enclosed space at different flow rates, and to show the impact of one important determinant of simulation accuracy.CFD results and measurements were compared, showing a good correspondance for the pollutant concentration when the boundary condition was a profiled velocity inlet and not an uniform velocity inlet.

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