The occupant's behavior with respect to window opening may greatly affect the ventilation system, the energy consumption orland the indoor air quality. In order to quantify the magnitude of opening times, many surveys have focused on climatic parameters and concluded to the temporal correlation between the timelength of opening and the outside temperature or the solar irradiation. In this paper, we study the influence of sociological and technical parameters on the average time of opening during the winter.
Describes the activities of Annex 18, whose objectives have been to develop means, methods and strategies for DCV systems and to contribute to the implementation. A DCV system in this annex is defined as a ventilation system in which the air flow rate is governed by airborne pollutants.
A literature search was performed to gain as much knowledge as was available on ventilation, indoor air quality sensors and demand controlled ventilation (DCV) strategies. Field data was gathered on the time and spatial variation of indoor air quality in houses. Appropriate designs were then developed. Design strategies are discussed elsewhere (1). Hour by hour simulations of the performance of several ventilation systems in various Canadian climates were done. Energy savings were then estimated for DCV and heat recovery ventilation with air to air heatexchange.
A passive tracer gas technique has been used in an experimental study of the distribution of contaminants in a room with displacement ventilation. Humans are simulated by heated metallic bodies and the tracer concentration in the breathing zone (exposure) is shown to be greatly influenced by both the position of the tracer source and the air convection current around the bodies. It is shown that pollutants emitted close to a body are completely and directly transported to the upper mixed zone and not mixed into the lower zone.
A test programme has been designed to evaluate the performance characteristics of sensors for the automatic control of ventilation rates. The test programme consists of two main parts, one being the evaluation of sensor performance in laboratory tests and the other referring to long term characteristics of sensors in actual buildings. Included in thepresent evaluation are eight different types of humidity sensors, two carbon dioxide sensors and five mixed gas sensors.