【国外标准】 Standard Test Method for Detecting Leaks in Nonporous Packaging or Flexible Barrier Materials by Dye Penetration

4.1 Contaminants may enter the package through leaks. Alternatively, product may be lost from the package through leaks. These leaks are frequently found at seals between package components of the same or dissimilar materials.4.2 Ingress or egress of gas or moisture through leaks in a package can also degrade sensitive contents.4.3 There is no general agreement concerning the level of leakage that is likely to be deleterious to a particular package. However, since these tests are designed to detect leakage, components that exhibit any indication of leakage may be rejected.4.4 These procedures are suitable for use to verify and locate leakage sites. They are not quantitative. No indication of leak size can be inferred from the test. Therefore, this method is employed as a go/no-go test.4.5 These tests are destructive. No package or component test samples exposed to dye penetration testing may be used for final product packaging.1.1 Method A of this test method defines a procedure that will detect and locate a leak equal to or greater than a channel formed by a 50 µm [0.002 in.] wire in the edge seals of a nonporous package. A dye penetrant solution is applied locally to the seal edge to be tested for leaks. After contact with the dye penetrant for a minimum specified time, the package is visually inspected for dye penetration or, preferably, the seal edge is placed against an absorbent surface and the surface inspected for staining from the dye.1.2 Method B for this test method also defines a procedure that will detect and locate a leak equal to or greater than 10 µm [0.00039 in] diameter in a nonporous flat sheet. The flat sheet is placed on an absorbent surface and then a dye penetrant is spread across the surface of the sheet, preferably using a small roller to apply pressure on the sheet to ensure adequate contact between the absorbent surface and the bottom surface of the sample being tested. The flat sheet is carefully removed and the absorbent surface is inspected for staining from the dye.1.3 These test methods are used for both transparent and opaque nonporous surfaces.1.4 These test methods require that the dye penetrant have good contrast to the materials being tested and/or the absorbent surface.1.5 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.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.