Standard Test Method for Evaluation of Solubility, Diffusivity, and Permeability of Flexible Barrier Materials to Water Vapor
|Publication Date:||10 February 1997|
|ICS Code (Waterproofing):||91.120.30|
1.1 This test method covers the evaluation of mass transfer properties of water vapor in films, plastic sheeting, coated papers and laminates. Barrier properties reviewed and specified within this method include solubility, diffusivity and permeability coefficients. This method also includes the means to determine the temperature dependence of these parameters.
1.2 Diffusion and solubility coefficients are particularly important in the evaluation of heavier gage plastic sheeting as well as paper substrates. These materials tend to absorb substantial amounts of moisture and to equilibrate over substantial periods of time. Predicting the field performance of these materials therefore requires the means to estimate the rate of approach to equilibrium and the degree of moisture absorbance in addition to permeability.
1.3 This test method assumes that the material being measured exhibits Fickian behavior. Measurement values are derived by a regression on the solution to Fick's first and second laws for a planar medium. These solutions are outlined in Annex 1 and are also addressed in Crank.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.