Numerous ground-coupled air systems have been constructed in combination with heat recovery units in mechanically ventilated buildings in Switzerland. The objective of this study was to investigate the microbial content within these ventilation systems and to monitor the quality of the air supply. The concentrations and the types of microorganisms in the outdoor air, in the air of the pipes and in the supply air of twelve groundcoupled air systems were determined. In addition, three buildings were examined four times a year to cover seasonal changes.

Ventilation system designers may be guilty of professional negligence by working with inaccurate noise data and, even worse, they may be unwittingly causing Sick Building Syndrome. Ewen Rose reports

The need for individual control with manual overriding combined with controlled natural ventilation is discussed. It is made plausible that with these two facilities problems related with the Sick Building Syndrome can be avoided. This principle is applied in a so-call led passive climate system. A system is devised setting the level of heating and ventilation by controlling motors fitted to radiators, ventilation openings in windows, Venetian blinds and outside shading. Moreover, it will switch on the lighting when natural lighting is inadequate.

Statistics indicate that flying is the safest way to travet, but a trip on a ptane coutd be more hazardous to your health than you might imagine. Carolynne Dear reports.

Recent concern has centered on "sick buildings" in which there has been an unusually high percentage of health complaints by the building's occupants. Typically, these symptoms are thought to be tied to indoor air quality characteristics, such as high levels of respirable particles or volatiles, thermal conditions, etc. In addition, recent studies have drawn connections between "sick building syndrome" (SBS) symptoms and non-environmental variables, i.e., personal and occupational factors. This paper presents a brief review of a study by Hedge et al.