Air networks are very important in indoor air quality of the patient environment. Qualitative and quantitative criteria for the design, installation and maintenance of the air network must be defined in the project.

For hospitals, air filtration is obviously a very important point in the control of nosocomial infections. A strategy and reference points are presented .

In hospitals, legionella, humidification and indoor air quality can be mastered with simple technical equipment.

Comments about the project of the new french standard NF S 90-351 "Clean rooms and related controlled environments in medical establishments" and the consequences on the design approach of clean rooms to master airborne contamination are given.

The french standard NF S 90-351 has been modified to include a wider field of application. This standard now takes into account previsional aspects. It is needed to define "areas at risk", and materials and equipment performances.

Air tighness of ventilation network is very important, so the manufacturers have developped sets of new sealed fittings. These new equipments have been tested in CETIAT laboratory. Results show good performance in term of air tighness and installation time.

Results of on site measurements in office buildings relative to the performance characteristics of five ventilation networks are presented. The poor air tightness is responsible for defects and bad performance.

The new French regulation about energy performance of buildings (RT 2000) specifies airtighness criterion for ventilation network. The author gives a methodology to measure the overall airtighness of ventilation installations on site. Examples based on a school and an apartment building are given.

The objective of this European Directive, which has to be transposed in national laws in European countries before 4 January 2006, is to promote the improvement of the energy performance of buildings, taking into account outdoor climatic conditions and local conditions, as well as indoor climate requirements and cost-effectiveness.
The directive lays down esuirements as regard :
a - the general framework for a methodology of calculation of the integrated energy performance of buildings (including aspects such as ventilation and indoor climatic conditions);

This document describes the designing process of a smoke management system for an atrium, using tools going from empirical equations to complex models, in order to have a safe evacuation of occupants in case of fire.