This paper discusses how ventilation and air distribution can have a positive or negative impact on chemical, biological and radiological agents entering buildings, on their movement within the buildings and on their removal. It also points out the key role played by the envelope airtightness of the building and its pressurization as a security tool.

Advantages and drawbacks of a Displacement Ventilation system are presented in this paper, in comparison with the traditional "mixing" ventilation cooling systems.

The first part of this article insists on the importance of a good ventilation system (polluted air exhaust, humidity, filtration, VOCs exhaust). The second part deals with a test house, equipped with either decentralized or centralized ventilation system. CO2 and ventilation rate measurements being compared, the validation of a model for the determination of the indoor CO2 concentration levels in one room of the house has been made.

A kind of protocol for the desinfection of air-handling ducts is presented in this paper with its different steps : relationship with the customer, available techniques, prerequisites for the desinfection, choice of the products and the desinfection itself.
The limits of the system are presented too along with possibilities to develop.

The search for top quality is the requirement of the professionals of "hygienisation". A description of desinfection with its methodology applied to ducts is presented : dust removal, cleaning of the surfaces before their disinfection.

Has the DOAS the ability to provide sufficient air movement to meet comfort requirements ? The test results from a DOAS delivering the minimum ventilation air via overhead high induction diffusers are presented in this paper.

In this paper, the author presents what could be done to improve the poor indoor air quality in some schools :- A demand for accountability from school systems about maintenance procedures such as roof-leak repair, classroom ventilation and air-conditioning, presence and care of carpeting etc.- A promotion of a responsible and adequate funding for the maintenance of public facilities- The most important activity is a good, basic, responsive and adequately funded building maintenance.

Standard 55-2004, on thermal Environmental Conditions for Human Occupancy was recently published and approved by ASHRAE and ANSI. This article gives an overview of the key features and limits of applicability of that standard.

In so far as prevalence of asthma and allergies is different from East to West Germany, a suggestion that it was associated with lifestyle factors was made. The endotoxin levels in dust collected from more than 4000 infants and mothers mattresses were compared. But none of the predictors analyzed and even a combination of predictors can be used as a surrogate for high or low mattress dust endotoxin levels in epidemiological studies.

This paper reports on an investigation of the adequacy of CFD for the predicting isothermal pollutant transport in a large indoor space with simple geometry, no furniture and no occupants. Agreement between predictions and experimental measurements was good.