health

The objective of this paper was to illustrate the potential of the CFD technique to compare the effectiveness of different general ventilation systems in reducing the workers' exposure to styrene vapour in a workroom. . Thanks to the CFD technique predicted airflow velocities and styrene distribution are shown for the 3 different ventilation arrangements at identical planes across the room. And predicted values of styrene concentration at workers'position are given.

European radon research and industry collaboration concerted action (ERRICCA2) is establishing a European scientific led industrial forum aimed at reducing risks to health from radiation (principally radon) in the built environment. It brings together 35 organisations from 20 countries.

A poor ventilation in buildings costs considerable amounts of money for hospitals and businesses.10 % of hospital acquired infections are directly due to an airborne route. The quantity and the quality of air supplied is important but also the way it is introduced into spaces. A change of the Wells Riley equation (establishing a link between the likelihood of infection, the infective agent production rate, the exposure time, the pulmonary and room ventilation rate) is proposed to take into account ventilation eefectiveness.

An intervention study was carried out in eleven elementary schools in Trondheim, Norway. Three schools with poor ventilation standard, four schools with carpets, and four reference schools participated. Carpets were replaced by vinyl flooring and the poor ventilation systems were upgraded. Altogether 1100 children aged twelve to thirteen years and 400 teachers were all included in the study. The baseline registration of health related symptoms was performed during January/February 1997. The questionnaires were repeated, after the interventions, in February 1998 and 1999.

At first, this paper deals with the history of indoor environment and ventilation , with the evidence that a good IAQ is essential for public health. An inadequate ventilation plays a major role on the global burden of allergies, airways infections. The more complex the HVAC system is, the more liable it is to fail (if improper maintenance) sothe non-industrial indoor environment is the most important environment from a human health perspective.

Fiberglass duct interior liners with and without biocides were submitted in an environmental chamber during 15 days to high air humidities, moisture and nutrient. Conclusion is that liners with biocide reduce microbial growth under high humidity as long as they remain dirt free and dry. Impermeable smooth liners show better performance than liners with porous or rough surface.

A Norwegian research project in under progress to develop a new concept for control of air movements in protection isolates, operating theatres and other risk areas in hospitals. The aim is to reduce airborne hospital infections through appropriate design of building, HVAC installation and control of air movements. A container solution was developped for isolates. Its HVAC system, and especially the ventilation system are described in details. The first container has been finished in June 2002 to be tested.

In an environmental lab with a panel of 30 women exposed 4 hours, comfort and health have been detremined both with a used or a new filter present in the ventilation system. All other environmental parameters were kept constant. A used filter in a HVAC system can have a negative effect on both the immediate perception of the indoor air quality and on perceptions and health-related symptoms. However, the annoyance experienced through the sensory system may have amplified the intensity of symptoms.

Relationships between research about indoor and outdoor air quality are reviewed. The author mentions that outdoor air pollution has attached greater regulatory interest, although people spend more time indoors. The contribution of exposure to indoor pollutants is now more recognized but this increased consideration has little effect on regulations. Nevertheless, the author considers that indoor air quality researchers and public health officials have a lot to learn from the outdoor air quality experience, in fields such as exposure, dosimetry, health effects and risks, mixed exposures.

The risk of contaminant deposition (10 microns particles) on an operating room surgical site is evaluated for different ventilation systems - conventional, laminar, non-aspirating, displacement -, using airflow modeling and particle tracking methodologies. Results show that laminar flows are the most appropriate to avoid particles deposition.