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Various air cleaning technologies and products are commercially available to remove VOCsfrom indoor environment. By conducting full-scale chamber tests, this paper compares theremoval characteristics for VOCs between three commercial portable room air cleaners,representing three major types of technology: sorption filtration, ultraviolet-photo-catalyticoxidation (UV-PCO) and ozone oxidation.

The paper presents part of the outcomes from the project set up by the Polish Committee forScientific Research and devoted to development of the recommended control strategies forDemand Controlled Ventilation (DCV) systems in Poland. The performance of both differentCO2-based occupancy detection algorithms for online demand controlled ventilation systemsand different methods of digital filtration of signals have been studied.

The survey concerned three swimming pools using a similar type of basic water treatment, buthaving different structures and ventilation systems. The survey included measuring air currentvelocities above the pools and studying the microbiological and physico-chemical quality ofthe pool water. In addition, microbes were determined from the indoor air, structures andventilation systems, and airborne particles and volatile organic compounds from the indoor airsamples. The total particle concentration of the indoor air and their size distribution variedbetween the swimming pools.

Air supply diffusers used in air-conditioning systems can be classified as ceiling diffusers,side-wall diffusers, floor diffusers, jet nozzles and low velocity displacement diffusers. Fixedor adjustable slats are usually used to control airflow directions. Recently, swirling vanes areused in floor diffusers to create a swirling out-flow jet, so that more rapid mixing withambient air can be achieved.

The objectives of the present work are to use computational fluid dynamics (CFD) to studythe airflow pattern and to evaluate the effectiveness of the passive cooling design of theproposed Jurong General Hospital (JGH) using natural wind. The complex three-dimensionalCFD model is used to assess the environmental conditions at the deep podium inside the JGHcomplex with prevailing wind conditions in Singapore, corresponding to the monsoon(November-February) and hot (March-October) seasons.

Tracer gases are often used to assess airflow rates in air handling units. Published methods aremostly designed for units with recirculation ratios lower than those commonly found inSingapore and other tropical countries. Large recirculation ratio homogenize theconcentrations, so that concentrations in supply and extract ducts are close to each other. Inaddition, such units often present a large time constant, so the time needed to reachequilibrium is very large. A procedure for tracer gas dilution technique adapted to such airhandlingunits is presented.

School indoor air quality has become of concern recently in Korea. In this paper, it is intendedto investigate the ventilation performance and thermal comfort characteristics of a classroom,when an outdoor air system is installed in addition to a ceiling-mounted heat pump system.Experiments were conducted in a full-scale model classroom to collect experimental data tovalidate numerical schemes. Three-dimensional temperature distributions were measured withthermocouples distributed throughout the space, and ventilation effectiveness was measuredusing a tracer gas technique.

This paper presents the indoor air quality performance of a displacement ventilation system ina thermal chamber. This study consists of two sets of experiments. In the first experiment, thethermal chamber was operated under displacement ventilation (DV) mode with the relativehumidity (RH) set at about 65% while the ambient temperature (AT) at 1.3 m height variedfrom 22 to 26C. In the second experiment, all the conditions are the same except that theventilation strategy is changed to mixing ventilation (MV).

Earlier studies have shown that airflows are not well balanced in office buildings. This maylead to too low ventilation rates in some rooms and too high ventilation rates in others.Several studies have shown that low ventilation rates may lead to a higher prevalence of SBSsymptoms. The reduction of these symptoms may be achieved with improved ventilation.The purpose of this study was to evaluate the benefits of balancing the airflows of the airdistribution system of an office building in Helsinki.

In order to effectively control nosocomial infection 12 respiratory isolation rooms fortuberculosis patients in four hospitals have been built by the Energy & Resources Laboratories,Industry Technology Research Institute in Taiwan. This project was funded by the Center ofDisease Control of the Health Department. The performance of the air-conditioning andventilation/exhaust system of respiratory isolation rooms has been tested and validated. Thetested items include ventilation rate, static pressure, temperature, humidity and noise.