English

The dour threshold value of kitchen exhaust air was experimentally determined during typical cooking situations and tobacco smoking in a dwelling. During cooking, air from the exhaust duct was taken into a sample bag. The dour threshold concentrations of the samples were determined by sensory evaluation using olfactometer and untrained dour panel. Experiments were made both in laboratory and field settings. The largest dour threshold concentration of 168 o.u./m³ was determined during the frying of herring.

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.

Fluctuating airflow thorough buildings is caused by temporal and spatial variations of wind-induced pressures around building envelopes, and include pulsating airflow and eddy penetrations. Two approaches using a multi-zone pulsating airflow model are introduced in this paper to study the eddy penetration and multi-way airflow through large openings. In the first approach, the eddy flow is considered to be caused by imperfect correlations among pressures at different points of an opening.

A prototype of a low cost, low energy office building was built using a new Finnish component system building technology. Thanks to the energy efficient windows, the thermal insulation of the building envelope and the demand-controlled variable outdoor air flow HVAC system with heat recovery and energy-storing structures, the need for heating and cooling energy has been reduced to such a level that a low energy office can be cooled with outdoor air and with the aid of a heat recovery device. The building is kept warm with the support of its own operations almost throughout the year.

Avery largeelectronics factory had beencompletely refurbished, and new mechanical ventilation systems installed. In an area of the factory where the principal activity was the bench assembly of small components, there were persistent complaints of eye nose and throat irritations, and absenteeism among the workforce was excessive. Careful examination of the environment had failed to identify any significant contaminants in the air. The situationwas similar to the SickBuilding Syndrome in office buildings.

Airtightness deficiencies of building envelopes and weaknesses in the ventilation systems can disrupt the operation of heating and ventilation systems. This can lead to an insufficient level of air quality and higher energy consumptions. In order to assess the performances of buildings and ventilation systems, CSTB has designed and developed different experimental devices for field testing. In a first step, an equipment was produced to measure the envelope air leakage. This apparatus is mainly used for research purposes.

By means of parametric analyses, the paper describes how the "constantness" of a Constant Air Volume system is affected by temperature differences resulting from heat load variations or otherwise. Several design related parameters are considered. The paper starts with the background, then an outline of the (simulation based) approach, and how calculations were performed. Results are shown with respect to consequences for volume flow rates and for energy consumption.

The classification of outdoor (ambient) air as fresh for the purposes of ventilation is not always appropriate, particularly in urban areas. In many cities of the world, urban air frequently violates health-based air quality standards due to high ozone concentrations. The degree of protection from exposure to ozone offered by the indoor environment depends on the relationship between indoor and outdoor ozone levels. Existing concentration data indicates that indoor/outdoor ozone ratios range between 10 and 80%.

Modern one-family houses in Scandinavia built before 1980 are often naturally ventilated and heated by electric baseboard heaters. The overall supply of fresh air is often inadequate during the heating season in many of these houses. Long periods of time individual rooms might get too little fresh air. The performance of a natural ventilation system is very much dependant upon the overall airtightness and the distribution of the airtightness of the building and the weather.

During the last decade several surveys in Sweden have indicated that the indoor climate in existing schools is unsatisfactory, therefore a thorough project was carried out in Växjö). The indoor climate was investigated in three schools during 1989. Detailed measurements were made of ventilation (e.g. rates, air exchange efficiency), indoor air quality (e.g. CO2) and thermal comfort (e.g. air velocity). The main results were: high indoor temperatures, low air velocities and high concentration of CO2. Improvements were made in all three schools during 1990.