A children's day care centre in Finland was the site of a study on the effect of ventilation and air filtration systems on indoor air quality. Indoor and outdoor concentrations of NO, NO2, TSP and PM10 were measured using automatic nitrogen oxide analysers and dust monitoring. Nitrogen oxides and particulate matter from traffic penetrated easily in the absence of filters.50%-70% of nitrogen oxides were excluded with chemical filtration. At holidays and weekends, the particle levels fell less than 10% of the outdoor level, rising to 25% on weekdays.
An investigation was performed on the indoor and outdoor air quality of fourteen public places in Hong Kong with mechanical ventilation. They included restaurants, libraries, recreation places, shopping malls, sports centres and a car park. Pollutant concentrations were measured during peak traffic hours at each sampling location. States that the results showed that the indoor/outdoor ratios at public places were higher than those at home and offices.
Indoor air contaminants may be grouped into four categories: microbial contaminants; respirable particles; gaseous contaminants, and vaporous contaminants. Conventional filters like HEPA filters can only be useful for bioaerosols and respirable particulate. Absorbers such as activated adsorbed can be useful for almost all gases and vaporous contaminant, but eventually they will lose efficiency. Photocatalysis can remove all VOCs and bioeffluent, but not very useful for gases contaminant such as ammonia.
One of the reasons for using displacement ventilation is that it may provide better indoor air quality in the occupied zone than conventional mixing ventilation. It is therefore important to understand the importance of the system on this aspect. A validated CFD model was employed to generate concentration distribution data for CO2, radon and moisture in a Hong Kong shop with displacement ventilation. Analysis found that the concentration distribution affected by factors such as the source type and location, its associated plume strength and human body convection, etc.
States that many environmental parameters need to be considered when assessing the quality of the air in an indoor environment, with an emphasis on clear definitions. Outlines the factors that determine IAQ and provides guidance on how to design an appropriate sampling strategy for organic compounds in the vapour phase. Reviews the present state of development of European and international standards for methods of measurement of indoor air pollutants.
In urban areas, people stand the most of their time in indoor environment. In this context, indoor air quality is more and more a subject of concern. Outdoor air quality can have a large impact on indoor air quality. An experimental study has been conducted into a dwelling, in collaboration between the LHVP and the CSTB, in order to study the indoor concentration of pollutants depending on the outdoor pollution and the air renewal due to ventilation system. Different experiments have been conducted in an empty dwelling situated in a polluted area in Paris during winter and summer periods.
Describes a study which examined the effect of temperatures of 23, 29, and 50 Deg C on formaldehyde and volatile organic compounds (VOCs) emission from laminate flooring Type A (with particleboard as substrate) and Type B (with high density fibre (HDF). For the first two temperatures, the measurements did not show any emissions of formaldehyde and very low emissions of VOCs. At the highest temperature however, Type A showed a high initial emission of formaldehyde and VOCs, decreasing with time. There were much lower emissions from Type B.
The Field and Laboratory Emision Cell (FLEC) was presented for the first time at the Healthy Buildings Conference in 1991. The FLEC is now used worldwide for many different applications that are related to emission testing of building products. Several labelling schemes are now on the market using both the FLEC and more classic climate chambers to fulfil the increasing demand for more indoor environmentally friendly building products.