On the time-dependant efficiency of building ventilation on the indoor air quality in a medium sized urban area in Greece.

From an air pollution study in a medium-sized, seaside town in Central Greece (Volos) it wasfound that some common air pollutants (CO, NO, NOx, SO,, 0,), whose emissions are connectedto activities and conditions that reveal some characteristics of periodicity on a daily,weekly or yearly basis (e.g.: production activities, meteorological conditions), are monitoredin the atmosphere in concentrations that reflect this periodicity.

Comparison of IAQ performances of French ventilation systems in residential buildings.

Until now, there is no widely accepted way to express any index for this purpose and takinginto account the large variety of possible pollutants. Things can be simplified is the aim is moreto compare different systems and strategies than to give an absolute value of quality.For the study of a pollutant source, the main important point for comparison is the pattern ofits production, whatever this pollutant is.

Aerosol Deposition in Turbulent Channel Flow: Implications for Energy-Efficient Indoor Air Quality Control

The occupants of buildings are exposed to a range of aerosol contaminants, of both indoor and outdoor origin; at present, filtered mechanical ventilation is the only effective means of airborne particulate control in polluted urban areas. Significant energy costs may be incurred, however, through the large pressure drops associated with membrane filtration. An alternative to filtration might be the enhancement of aerosol deposition on a protruding surface which is parallel to the incoming airflow direction, but which does not significantly retard the airflow.

Assessment of Indoor Air Quality and ASHRAE Standard 62

Today, laws and regulations play a major role in just about everything we do. The declining quality of the air in our buildings is causing movement towards regulations relating to how buildings should be designed and operated. It is important that designers and operators are aware of all current design and operating standards. ASHRAE Standard 62, "Ventilation for Acceptable Indoor Air Quality" developed in l 989 and now under revision, has created new challenges for designers and engineers.

Modelling supply devices in order to predict improvements in internal air quality.

The air distribution effects of floor mounted swirl diffusers are investigated and described inthis paper. Results are based on a case study of an office typical of those in urban commercialenvironments. The effects of the swirl applied to the supply air as well as temperaturedifferentials between supply and room air are explored. The investigation is restricted tosituations where cooling is required.The results of the work, which is undertaken by way of CFD analysis, are presented in termsof appropriate ventilation effectiveness parameters.

A Methodology to Assess the IAQ Performances of Ventilation Systems in Residential Buildings

Until now, there is no widely accepted way to express any index for this purpose and taking into account the large variety of possible pollutants. Things can be simplified if the aim is to compare different systems and strategies rather than to give an absolute value of quality. For the study of a pollutant source, the main important point for comparison is the pattern of its production, whatever this pollutant is. The detailed data for each inhabitant is the curve of the number of hours above a pollutant level concentration Ci: Nh (Ci).

Ventilation design options for IAQ in HVAC systems.

                 

Sensorial and Instrumental Approaches to Indoor Air Monitoring

The paper deals with a research about analytical techniques for meaningful, reliable, cost-effective, in-situ, real-time and continues determination of airborne chemicals, by means of a new electrochemical sensor; the research aims to develop objective instrumental sensing systems able to substitute the subjective human responses. Sensor detection capability could regard a series of analytes: carbon dioxide, carbon monoxide, inorganic pollutants, ammonia and other metabolic gases, irritants, odours.

Perceived Air Quality: Should We Use a Linear or a Nonlinear Scale for the Relation between Odour Intensity and Concentration?

Assessing the perceived air quality in decipols by trained panels can be performed rather perfectly today. To calculate the olf load from these results is a little more problematic as one requires olf loads which can simply be added (linearly). The reason for this difficulty is the nonlinear relation between the perceived air quality in decipol and the pollution load in olf. The relation can be expressed by an exponential function in a range between l to 15 decipols. Unfortunately the exponent and the constant in the exponential function differ for different substances.

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