office

Birch and grass pollen grains as well as pollen-derived small particles appear as potent allergens in the outdoor air during spring and summer. The occurrence of pollen allergens in indoor air, however, has not been studied in depth due to lack of suitable sampling and analytical methods. Herein; a recently reported "direct on sampling filter estimation" (DOSAFE) technique (Acevedo et al., 1998) has been validated for quantification of pollen allergens in indoor air using two school rooms and two office rooms as experimental models.

The characteristics of a hybrid air-conditioning system, utilising natural and mechanical 'task' ventilation, are investigated in an office setting. The characteristics of the indoor environment are examined by means of CFD (Computational Fluid Dynamics) simulations under various conditions of incoming outdoor air. The control of the task air conditioning system (VAV system) is included in the calculation through changing the supply air volume to keep the task zones temperature at a target temperature.

Ventilation and infiltration rates were measured in eight office buildings using an automated tracer-gas measurement system. The buildings range in size from a two-story building with a floor area of about 2000 m2 to a 15-story office building.

Describes how multizone tracer gas analysis techniques can provide a complete description of office ventilation. Treats the concept of ventilation effectiveness to characterise internal air distribution. Discusses the measurement of whole building ventilation rates and ventilation effectiveness in mechanically ventilated office buildings.

Describes case studies of two sick Canadian buildings. The first illustrates a comprehensive programme of measuring air quality, ventilation and thermal conditions as well as monitoring the performance of the heating, ventilating and air conditioning systems. The second illustrates use of a standard survey questionnaire with back-up field monitoring of environmental parameters. In the first building the ventilation system was found to be malfunctioning. In the second building the humidity was very low.

Describes validation of a simple technique for infiltration measurement in large, multicelled, naturally ventilated buildings by reference to a computer model study and by field measurements in two naturally ventilated office buildings. The salient features of the technique are: 1) a single tracer gasis used, 2) measurements need only be carried out in part of the building, 3) an initially uniform distribution of tracer is not needed, and 4) artificial mixing of the tracer with the internal air is not essential.

A cross sectional survey investigating building sickness was carried out in two buildings with similar populations of office workers but differing ventilation systems, one being fully air conditioned with humidification and the other naturally ventilated.

Incidence of building occupant health and comfort complaints (tight building syndrome) have been linked to energy efficient, mechanically environmentally controlled sealed building technology and systems now characteristic to most office, commercial and publica buildings.

Pollutants in a substantial number of buildings have now been investigated by public and private agencies. The archive of data on indoor pollutant levels observed in office buildings under conditions of normal operation and occupancy are reviewed using a computer based Building Performance Database. Representative values of 153 pollutants as well as detailed frequency distributions of commonly measured pollutants and of temperature and humidity are presented.

This paper reviews the literature on sources and levels of pollutants in buildings and looks at the possible effects of a reduction in ventilation rates on the health and comfort of building occupants.