Investigation and application of a model for porous foam aerosol penetration

Measurements of aerosol penetration through porous polyurethane foam plugs were carried out in order to develop a model describing the aerosol penetra tion behaviour. The data were found agree well with an existing semi-empiri cal model for porous foam aerosol penetration. This model was improved by r eformulating it to use consistent units, and accurately measurable input pa rameters. The model was implemented as part of a design spreadsheet, to des ign foam modules suitable for a range of specific aerosol monitoring applic ations. The design spreadsheet was validated by comparing its outputs with the known characteristics of a number of pre-existing foam modules, It pred icted the characteristics of these modules accurately, within the limitatio ns due to a lack of knowledge of the precise cell diameters of the foams us ed to make them. The use of the design spreadsheet to explore different opt ions for size-selective foam modules is illustrated. The results obtained h ighlight the importance of a reliable supply of foam, having closely specif ied cell diameters, in order to manufacture size-selective samplers meeting acceptable quality standards. Crown Copyright (C) 2001 Published by Elsevi er Science Ltd. All rights reserved.