Although a significant amount of work has been done to elucidate the conditions under which fungi will grow on the surfaces of materials, little information is available that quantitatively relates surface concentrations to airborne concentration and, ultimately, exposure. This paper discusses the impact of relative humidity (RJI), air velocity, and surface growth on the emission rates of fungal spores from the surface of contaminated material.

The aim of the experiment was to study the efficiency of three duct cleaning methods. The methods used were ( 1) rotating brushes, (2) compressed air cleaning, and (3) wiping by hand. The air handling systems under investigations had been in use 26 and 30 years after the construction phase and the systems had not been cleaned since buildings were completed. Accumulated amount of dust in the supply air duct was determined by BM-Dustdetector, tape method, and by visual inspection before and after cleaning. The amount of dust on the duct surface was decreased with all three cleaning methods.

The new Guideline VDI 6022 contains hygienic standards for ventilation and air-conditioning systems. The requirements for the planning, design, operation and maintenance of ventilation and air-conditioning systems and their components are dealt with to ensure a hygienic condition according to the state of the art. The Guideline is subdivided as follows:

• part 1 Offices and assembly rooms (published 07 /98)
• part 2 Standards for Hygiene training (published 12/98 as a draft)
• part 3 Factories (activities have been started 01/99)

Fungal-contaminated air handling systems have been implicated as a source for the dispersal of spores into the indoor environment, potentially serving as a route of exposure to building occupants. Because quantitative data are lacking, this study was conducted to measure the dispersal of spores from fungal colonies growing on three types of duct material: galvanized metal, rigid fibrous glass ductboard, and fiberglass duct liner.

Passive solar cooling for hot humid areas represents an important field for innovation, if we want to solve comfort needs in spaces (especially housing) designed to reduce economic, technical and health requirements. In urban areas or deep valleys and rain forests, which are common in most of the tropical equatorial countries, external breeze is not frequent and air speeds are too low to produce cooling, using a simple cross ventilation system. Since 1982 the author has developed new designs and constructions using passive solar techniques.

This study investigated the pressure flow characteristics over a number of fullscale modulated louvered windows (MLW). The various MLW parameters included louver inclination angle (8), depth (L), aperture (d) and the ratio of aperture/depth (d/L%). Airflow models were developed using both power law and quadratic model equations. By examining the coefficient of determination (r2) for both model equations, it was evident that the quadratic model equation suggested the best curves fit.