ventilation system

The communication presents the Technical Appraisal Procedure followed in France for Demand-Controlled ventilation systems through the illustration of the use of a thermo-hygro-aeraulic nodal model called MATHIS developed by CSTB. The calculations methodology is described. Its application is illustrated for different family of ventilation systems currently under the scope of the procedure. The needs and the current developments for a better modelling of Indoor Air quality are lastly exposed. 

In France, the new Promevent protocol for ventilation system inspection in new dwellings has been published in 2017. It proposes a complete method for checks and measurements in order to uniform and improve the quality of inspection performed by measurers. The Promevent protocol proposes a methodology for pre-check, functional checks, functional measurements at air terminal devices and ductwork airtightness measurement. It also includes requirements for sampling and gives guidelines for the report.

People in industrialised countries spend about 90% of their time indoors. Hence, a good indoor climate is essential for health and well-being. Ventilation of buildings plays an important role concerning health aspects of the occupants and inadequate ventilation may cause health costs that may have been avoidable if ventilation would have been adequate. Additionally, good or bad ventilation has impacts on the quality of the building, e.g. in very tight buildings, the risk of mould and dampness is higher if air change is insufficient.

The objective of this paper is to assess the impact of the envelope airtightness on airflow patterns for single detached dwellings depending on the ventilation system.

This study investigates the influence of outlet location on conventional, turbulent-mixing operating-room (OR) ventilation performance. This was done by numerical simulation using computational fluid dynamics. Multiple configurations of OR outlets, both at floor and ceiling level, were examined, and the results were compared. OR ventilation-system performance in each case was examined by conducting a tracer-recovery test. Two common anesthetic gases, halothane (C2HBrClF3) and desflurane (C3H2F6O), were used to perform the test.

The proceedings of the seventh AIVC Conference contain 16 papers and 5 posters as follows: Requirements for adequate and user-acceptable ventilation installations in dwellings; Ventilation air infiltration and building occupant behaviour; A preliminary study of window opening in 18 low energy houses; Occupants' influence on air change in dwellings; The influence of occupant behaviour on indoor air quality - a case study; Ventilation and occupant behaviour in two apartment buildings; Inhabitant behaviour with regard to mechanical ventilation in France; Ventilation heating system of small hou

The indoor environmental quality and health of occupants in approximately 5000 dwellings were investigated by questionnaire covering the whole of Japan. The purpose of this survey was to clarify the association between indoor air quality and adverse health effects and to study effective ways of keeping indoor air clean using mechanical ventilation. Questionnaires were distributed to 7812 occupants living in mechanically ventilated houses across 47 Prefectures in Japan in February 2012 of which 5265 occupants replied.

With the increasing need for higher energy efficiency in buildings, airtightness and ventilation systems choice become major performance issues in well insulated buildings. Buildings energy requirements lead to adapt ventilation strategies in order to reduce energy losses through mechanical balanced or extract ventilation. With the new French thermal regulation, the use of energy-efficient ventilation systems is implicitly required; low air infiltration is explicitly required in residential buildings through minimum airtightness levels.

Scientific studies have linked particulate matter with a series of significant health problems. In ventilation systems, indoor particle concentration and dust load on air duct surfaces are two concerns for human health. PROBE-PM (Predicting code for building environment-particulate matter transport simulation), a code to simulate the particle transport in the whole ventilation system is developed.

In this study, the characteristics of the movement of chemical compounds in the concealed spaces and indoor spaces in houses were investigated using building cut models and a simulation program Fresh2006. The equivalent leakage areas in the concealed spaces were measured using cut models of wooden structures: a common wooden structure, an improved wooden structure and a wooden (2 inch x 4 inch) stud structure.