Prise en compte de la charge électrostatique des filtres (Taking into account of the electrostatic charge of the filters)

This paper is a review of the existing methods and techniques that allow the reproduction in laboratory of the real behaviour of filters, mainly the electret filters. First, the principles of the ways the electret filters work are described, along with their performances when installed. Then the testing methods for filters are presented with the differences between the performances measured in laboratory and in-situ. Finally, the results of intercomparison tests organized by Cetiat 's company in 2004 for Eurovent on the basis of EN 779 Annex A - test methods- are presented.