A method for estimating the reliability of mechanical ventilation systems in dwellings hasbeen developed. The analysis is based on component level reliability models interconnectedby so called fault-tree schemes. A simplified model for maintenance is included. Theanalysis procedure is applied on an central exhaust ventilation system and on a central supplyand exhaust ventilation system with heat recovery. For each system, three different qualitystandards have been defined and combined with three levels of maintenance. Work has alsobeen done on collecting relevant input data, e.g.

The U.S. Environmental Protection Agency is seeking to improve the thermal quality of newhomes, most of which are being built in the sunbelt by large building development companies.Low-infiltration production (tract) homes need ventilation systems that satisfy the low-costpriority of the builders as well as the safety, health and low operating cost expectations ofhomeowners.

The main goal of IEA Annex 27 "Evaluation of ventilation systems" is to develop tools toevaluate ventilation systems in an objective way in terms of indoor air quality, energy,comfort, noise, life cycle costs, reliability and other building related parameters.To check the developed tools some measurements in real dwellings are necessary. Thedevelopment of the tools is in its final stage. During the AIVC conference some of these toolswill be presented. The indoor air quality tool is not yet ready.

The design of low-energy office buildings requires specific attention to an energy efficient concept for providing good indoor air quality conditions. With this respect, mechanical ventilation shows undeniable advantages: it can be optimally controlled (infrared detection, CO2 control,...), heat recovery is applicable, outdoor noise and pollution penetration can be minimised. Another crucial challenge in low-energy office buildings is avoidance or, if possible, the minimisation of active cooling needs.

The main source of humidity in office buildings is the human occupant. Moisture is therefore a result of heat transmission from the person to the room air. The article covers heat transmission of the human body, humidity and comfort, cooling and dehumidification, and refrigeration capacity.

This paper summarizes recent developments in natural and passive cooling in buildings and the main results from the European research project P ASCOOL. The project was completed at the end of 1995, after 2i'months of theoretical and experimental work resulting in a better understanding of passive cooling techniques and the development of tools and design guidelines. The project was a collaboration of 29 European universities and research organizations from 12 countries.

A new type of residence (the SEA house) has been proposed in winter, the house is heated by solar energy. Thermal insulation, heat storage, and air circulation are used to maintain the room temperature at a comfortable level and to reduce the temperature difference between the south side and the north side of the house. In summer, earth tubes are used for the purpose of cooling the proposed house. The thermal performance of the house was simulated by a computer program called PSSP, which can predict room temperature in a multiroom system.

Commercial cooking equipment exhaust systems have a significant impact on the total energy consumption of Foodservice facilities. It is estimated that commercial cooking exhaust ventilation capacity in food-service facilities across the United States totals 3 billion cfm (1 . 4 billion L/s) with an associated annual energy cost approaching $3 billion, based on an average of $1/cfm ($0.47 per L/s) per year. Significant energy and cost savings can be achieved by reducing ventilation rates.

This paper presents results of applying the capture and containment test procedures in ASTM Fl 704-96, Standard Test Method for Performance of Commercial Kitchen Ventilation Systems, to determine the threshold capture and containment exhaust flow rates for a number of cooking appliances and two types of kitchen exhaust hoods.