【国外标准】 Standard Test Method for Measuring the Yield for Aerosol Foam Sealants

5.1 The yield measurement of aerosol foam sealants is used to indicate the amount of foam sealant that can be obtained from a single container of product.5.2 The yield does not predict the performance capability of the foam sealant product or its suitability for the intended application.5.3 Procedure A was developed for use with products that can be volumetrically measured by submersion in water. Procedure B was developed for product that cannot be measured by using a water displacement method.5.4 Yield is often dependent on the bead size dispensed. Extrapolation of test results using data measured for larger size beads to estimate smaller sized beads has shown inaccuracies. Since yield will be reported based on the diameter of the cured bead (not initial size of wet beads), the operator shall determine the nominal initial bead size required to produce a specific nominal cured bead diameter. This foam characteristic, called “post dispensing contraction” or “post dispensing expansion,” is defined in Terminology C717.1.1 This test method determines the quantity of linear units of a foam sealant at a specified bead diameter that may be obtained from each container of an aerosol product. A minimum of four (4) representative containers of the aerosol product are required for this determination.1.2 The test method is intended to estimate the contents of the aerosol container (1) for purposes of label statements, and (2) to provide the user information needed to estimate job requirements.1.3 Foam sealants are used for a variety of end-use applications but are primarily intended to reduce air movement in the building envelope.1.4 Currently, two main foam sealant types are applicable to this standard: single component polyurethane and latex.1.5 Values are reported in SI units only.1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.