This paper presents the results of tests carried out on 7 different air cleaners : one with HEPA filter and the 6 others are ionizer models . The air cleaners efficiency against dust, smoke, pollen, emitted noise and emitted ozone was evaluated. The results present the HEPA model as the most performing whereas the ionizing air cleaners do a poor job of removing particles from the air and create significant levels of ozone.
The aim of that study was to determine the causes of Sick House Syndrome . 60 sick houses in Japan were investigated during six summer form 2000 to 2005. That field survey revealed that indoor air was polluted with high carbonyl compounds and VOC concentrations over the guidelines. There is a clear relationship between indoor air pollution and the causes of symptoms in houses.
Three different air purification devices were investigated for that study : two photo catalytic oxydation (PCO) units and one gas-phase adsorption (GPA). The benefits of the GPA were significantly demonstrated. And this technology appears to be an attractive solution to improve aircraf cabin environment.
That study was carried out in a general hospital ward in Hong Kong, equipped with ceiling-mixing type ventilation system to analyse the dispersion characteristics of expiratory droplets. A model has been used to simulate the motion tracks of the droplets and droplet nuclei. The results show that the dispersion characteristics were size-specific and highly affected by the ventilation air flow pattern. The laterally projected air jets should be avoided in ward ventilations.
The survey has been carried out in two nursery schools located in Strasbourg to quantify both the formaldehyde levels and the air change rates of three classrooms investigated two days continuously, one day with and one day without the presence of children.The results show the impact of ventilation rate on formaldehyde levels.
The article compares the energy consumption linked to different ventilation systems of an office room (22 m2, 3 m high, occupied by 2 persons from 8 a.m to 6 p.m, internal heat source 15 W/m2). Those systems are : air renewal through windows opening, classical control mechanical ventilation with heat recovery, high energy efficient control mechanical ventilation with heat recovery. The mechanical systems provide 40 m3/h/person (air change rate 1.2 vol/hr).
A field experiment was conducted in a primary school in 3 steps : first Personal Air Quality (PAQ) was assessed with the used bag-filters present in the air supply path, then when the bag filters had been removed, and finally when filters were refitted. The results showed that PAQ was better when the filters were removed, the author find it urgent to improve standards and filtration products for comfort ventilation.
A statistical interpretation of nearly 8 000 individual questionnaires on perceived indoor environment has been made. Results show several correlations found between comfort complaints or presence of SBS symptoms and the characteristics of offices and apartments indoor environment.
In this paper a number of comfort indicators required for the assessment of indoor environmental building performance are presented, they both include temporal variation and the degree of discomfort perceived by the occupant. A test case using thermal building simulations is applied on a ventilated office building
For that study indoor and outdoor temperatures were recorded (respectively every 20 s and 1 minute) for 10 apartments houses in Japan during summer-autumn with the intention to investigate the relationships between ratios of air conditioner use and window opening. The method and results are presented.
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