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.

This paper presents a new technology for capture and containment testing in commercial kitchen ventilation research. It is called large-scale focusing schlieren system and offers a nonintrusive approach to effluent flow observation. Schlieren systems can be added to conventional kitchen ventilation research laboratories or other hood testing facilities and allow continuous observation of a large area around a hood-appliance setup.

Laboratory hoods are designed to capture contaminants generated in the laboratory and discharge them outside. In many laboratories this results in several fan systems. To provide a convenient location for maintenance to service the fans, the fans are often located in penthouses. Good design of laboratory ventilation requires that the duct be negative in occupied spaces. However. it is not possible to design a fan room or penthouse with the duct negative downstream of the fan.

The use of the laboratory fume hood as the primary containment device in the laboratory has been a standard practice for almost half a century. Quantitative testing of the performance of these devices, however; is a more recent discipline. The use of the ANSI/ASHRAE 110-1995, Method of Testing Performance of Laboratory Fume Hoods (ASH RAE 1995) is becoming a standard specification in the purchase of new fume hoods, the commissioning of new laboratory facilities, and benchmarking fume hoods in existing facilities.