English

This paper gives as a posthumous tribute to Walter Dittes, a summary of his thesis prepared at the University of Stuttgart (Germany) .It describes the various air diffusion patterns that can be used (mixing ventilation, displacement ventilation or use of both in different zones), and explains how thermal plumes are treated according to the chosen pattern.A zone model is then described for the prediction of air flows and pollutants transfers between zones within the indoor space.

This paper presents the requirements of the new European standard EN 13779 (2005) that replaced the German standard DIN 1946 Part 2 (1994). It has to be used in combination with the German recommendation VDI 6022 Blatt 1 for the design of ventilation systems fulfilling the requirements regarding indoor air quality.

Interdisciplinary research was based on simultaneous measurement of thermal environment and air quality, along with the survey of employees during their normal working activity. Statistical software and appropriate statistical methods were used to analyze the results of the questionnaire and to determine possible links with the indoor environment parameters.The results show the importance of psychological factors in subjective evaluations of the thermalenvironment.

The purpose of the present investigation was to study the indoor climate and the psychosocial work environment in different office environments.A cross-sectional questionnaire survey was performed in 11 naturally and 11 mechanically ventilated office buildings. Both buildings with cellular, multi-person and open-plan offices were studied.

Sick Building Syndrome or Sick House Syndrome (SBS/SHS) has become a serious problem in Japanese daily life.This survey was conducted in 53 houses in Miyagi prefecture during four summer seasons from 2000 to 2003 to understand the states of indoor air pollution and occupants health conditions in dwellings suspected as Sick Houses.It appears that the relationship between chemical substance concentration and subjective symptoms is not clear and the causes of symptoms are different between individuals.

The transmission paths of infectious diseases remained a myth up to now.Our hypothesis is that, on windless days, the outflow from a window on the lower floor of a building will re-enter the immediate upper floor, and therefore bring the droplet aerosols upstairs. The objective of this project is to reveal the mechanisms of this airflow by actuallyquantifying the fraction of the lower-floor exhaust air within the intake air of the adjacent upper floor.

In 2003, a SARS negative pressure isolation ward was built in Beijing to isolate patients. According to it, the authors carried out a numerical simulation and validated the experiment to optimize the indoor air distribution for it. They also compared the results from the simulation with those from measurement.As can be seen from the simulation, an acceptable airflow pattern is obtained in most places of the isolation room.

A downward ventilation system has been proposed as a standard ventilation design by Centers for Diseases Control and Prevention (CDC) in Hong Kong for isolation rooms. This paper deals with the effect of a downward ventilation system in a general ward to test whether it could reduce the risk of cross infection. The dispersion of exhalation pollutants and exposure of receiving patients in a general ward was studied.

This paper presents the first design code for sports buildings in China : it includes an important chapter on indoor air environment dealing with indoor air velocity, temperature, humidity and fresh air volume.This code could be a guide for the designing of indoor air environment of sports building, especially for the Beijing Olympic game in 2008, and is useful to help advanced HVAC design and analysis on the similar large space buildings.

This project brought together, during a two-day meeting, six experienced IEQ investigators with decades of combined problem-solving experience in thousands of buildings. A group process gathered and synthesized their knowledge about : - the key environmental factors causing building-related symptoms in office buildings and- the key strategies for preventing these problems. Those empirical results were compared to current scientific knowledge and summarized for use in developing practical guidelines for maintaining good IEQ.