According to the authors, there is a way to increase levels of filter efficiency while reducing the expense of the upgrade. The objective is to define the lowest cost system and not the lowest price system : to determine the best filter for the best cost. The 3 major components to life-cycle costing formula are initial investment and maintenance (that can easily be computed), energy consumption and disposal (that are more complicated to analyze). Examples are given.

In this article a conventional DX system is compared to three other all-electric enhanced dehumidification DX system packages to provide insight into their respective preformance capabilities. The author's conclusion is that augmenting a conventional DX cooling coil with enhanced dehumidification components (such as a wraparound heat pipe heat exchanger, a desiccant dehumidifier in a wraparound configuration too, or a post coil desiccant dehumidifier regenarated by condenser waste heat) can substantially increase an integrated system's moisture removal capacity.

The SEF (system effect factor) causes loss of capacity of fan volume attributed to poorly designed and installed duct fittings at the inlet or outlet fan. It is the interaction of the air with obstructions such as elbows, guards, drive sheaves or dampers, that create SEF.
So SEF must be considered at the design stage of a fan system, it must be included as a separate item in the fan equipment schedule. Ignoring SEF has heavy cost implications.

In the first part of this paper, the techniques that allow the reduction of the radon exposure in buildings are presented. And in the second part, the authors present the results of studies that have shown the links between radon exposition and health. In conclusion, the authors assert that the risk of lung cancer due to a domestic exposure to radon is obvious.

Ashrae 52.1 and 52.2 test standards have been of great value in providing classification methods to compare and contrast filter performances. But they were criticized too, becauset the exposure of electrostatic filtration media to "real world" air results in a performance below the efficiency determined by the Ashrae 52.2. Test.

In this paper the development of international standards for filters used in general building ventilation and for gas turbine intake air cleaning is examined. CEN (Comit Europen de Normalisation) and ISO (International Standards Organisation) have working groups with European or worldwide membership to write european or international air filter standards and rating systems.

The method presented in this paper is called DIAGVENT, it was set up by the CETIAT (Aeraulic and air handling technical center) to provide the professionals a practical tool for the diagnosis of the ventilation installations in residential buildings and offices.
It relates the on-site practice, applying a Swedish experience at different French cases .
Three levels of diagnosis are presented :
Diagvent 1 for the checking of the good achievement of the ventilation installations.

The French car group Peugeot-Citroen has been using for several years the perforated textile ducts at high induction Mix-ind for the heating of its industrial premises.That air diffusion technique uses the blowing air to start the moving of the ambient air at a very low speed.The ambient air inducted around the duct is mixed with the blowing air, so very quickly the temperature of the air inside the premises is homogenized.

This study shows that the removal of combustion products formed during cooking is more efficient in the newer homes than in those studied in the early-to mid-1980s. Realtime measurements were made of CO, CO2, temperature, and water vapor in 74 kitchens in Netherlands. Their inhabitants kept a diary during the measurement period about their cooking and ventilation behaviour, and answered an individual questionnaire too.

In this paper, the authors have studied the oxidation processes on air filter surfaces initiated by ozone. Ozone concentrations were monitored upstream and downstream of used and new filter samples using a small-scale test rig at two different airflows.Test results have shown that the removal of ozone by a loaded filter decreases over time then gets steady. Though necessary, the filtration of ozone creates oxidation processes that are responsible for the generation of products that affect the perceived air quality mainly after periods when the ventilation system is not in operation.