PR1999

Avariety of gaseous pollutants in indoor air now are becoming an object to control. Thus, westudied a removal technique using TiO2 photocatalyst under 365 nm or 254 nm UV-lightirradiation for toluene, benzene, formaldehyde and acetaldehyde as examples of hazardousvolatile organic compounds (VOCS), in order to get detailed analytical data for productsderived from these contaminants. Although these compounds were effectively destructed, notonly CO2 but also high concentration of toxic compounds, such as aldehydes were formed inthe case of under 365 nm UV-light irradiation.

As part of an ongoing investigation on service life of air filtration material, a new type of airfiltration material (multi-layered polymer) was compared with a widely used material todetermine growth or survival of micro-organisms after normal dust loading. Blinding wasperformed by the manufacturer supplying the materials as anonymous A and B. Microorganismswere extracted after 2, 4, 6, and 8 weeks by washing (shake out) and plating thesolution onto agar media, incubated and differentiated. Vital fluorescence microscopy wasalso performed. The results showed a significant difference (P

Air recirculation in the new office and laboratory building of the Norwegian Institute for AirResearch was discovered and characterised from a leaking sulphur hexafluoride cylinderstored in the garage. The garage/staging area was located at the far end of the right wing ofthe three-storey building, and was used for loading/unloading of equipment and for storage ofequipment and compressed gas cylinders. Sulphur hexafluoride tracer was detected in thecorridor on the ground floor right wing leading to the central reception area.

Models are presented for describing the performance of room air cleaners in removing pollutants from indoor air, particularly the levels of removal that can be achieved in practice. Controlled levels of pollutant were generated in a room environmental chamber, and the performance of a commercial room air cleaner was assessed according to the models. The room environmental chamber was operated in static (sealed) or dynamic (ventilated) modes.

Snow has already been used effectively as a cold energy resource in some heavy snowfall areasin Japan. As the surface of snow is covered with cold melting water when snow is used as a coldenergy resource, we can expect gas absorption on the surface. By this mechanism of the gasabsorption, some airborne contaminants such as dust or harmful gases can be removed by themelting snow surface.

This report describe the thermal performance and air distribution of a Kumamoto prefecturalindoor sports ground in Japan. The swirling flow type natural air ventilation system wasadopted in combination with environmental symbiotic technique, and attempts was made topositively harmonize the system with the environment. In the measurements, emphasis wasput on the identification of thermal environment and on the verification of the swirling flowtype natural air ventilation system.

In apartments of Korea, exhaust-only hood system is commonly installed for kitchen ventilation. However, as to resident's increasing complaints recently due to poor indoor air quality and hood noise, a careful review regarding kitchen ventilation system came to be in need. This paper presents a research that was conducted to improve ventilation problems in the existing kitchen of apartments. For this purpose, a field test has been carried out to examine the effect of range hood's exhaust airflow rates, and makeup air inlet's settings on kitchen ventilation efficiency.

Three very different task/ambient conditioning (TAC) systems were investigated in a climate chamber. Two desk-mounted TACS, the “Personal EnvironmentalModule” (PEM), intended for US offices, and the “ClimaDesk” (CDESK), intended for European offices, were compared experimentally with a floor-mounted unit, the “Task Air Module” (TAM). All three provide some individual control of cooling, while PEM and CDESK also provide individual control of heating.

During the experiments and under the experimental conditions, displacement ventilation with air outlets close to floor level were found to produce the lowest concentrations of hazardous substances and aerosols in the working areas of kitchen appliances when compared with mixed or displacement ventilation through ceiling outlets. Displacement ventilation with low-induction ceiling outlets achieved better results than mixed ventilation.

Recent years have brought the popularity of methods in which neutral networks are applied. They seem of particular importance while dealing with diagnosing, predicting and estimating. Those methods rely on collected data base, simulation and interpolation in the so-called learning process. There are attempts at neutral network application in building engineering. The paper sums up the initial phase of research on neural applications in the air exchange estimation.