ASTM F903-18

5.1 This test method is normally used to evaluate the barrier effectiveness against penetration of liquids through materials, seams, closures, or other planar assemblies used in protective clothing and specimens from finished items of protective clothing.

5.2 A substitute challenge liquid (for example, water or isopropanol) is appropriate in some cases to generalize material penetration resistance to liquids. However, it is possible that differences in chemical and molecular properties (for example, surface tension) may lead to different results.

5.3 In addition to the failure mode where a liquid finds a pathway for penetration through a void, imperfection, or defect in material or clothing subassembly, some selected chemicals cause degradation of barrier material, film, or coating, leading to penetration over extended periods of contact.5.4 Five different procedures for how the specimen is exposed to the liquid are provided in Table 1. In this test method, all procedures involve liquid exposure that is continuous over the duration of the test. These procedures entail different hydrostatic pressures and durations of liquid exposure.

5.5 Different results are reported by the different procedures.

5.6 The choice of pressure/time sequence and type of test result are dependent on the objectives of the testing.

5.7 This test method permits the use of a retaining screen for preventing the overextension of a specimen as pressure is applied. However, it is important that the selected retaining screen does not interfere with the observation of liquid penetration or affect the sealing of the specimen in the test cell.

5.8 A critical feature of the test is how the specimen is sealed in the test cell. Inadequate sealing of the specimen can lead to a false result (observed liquid penetration that is due to the method of sealing rather than penetration through the specimen). It is recommended that any special means used to seal specimens in the test cell be validated for providing sufficient integrity of the specimen in the test cell, not contribute to specimen damage, and not interfere with the observation of liquid penetration. Special means used to seal specimens in the test cell should be documented in the report.

5.9 A minimum number of three test specimens is established for this test method. However, it is also appropriate to establish sampling plans based on a specific acceptable quality limit using a larger number of specimens, depending on the application of the test method. Potential sampling plans for this approach are found in MIL-STD-105E, ANSI/ASQC Z1.4, and ISO 2859-1.

5.10 This test method does not address the liquid penetration of full protective clothing or ensembles. Use Test Method F1359 to provide a complete evaluation of the liquid integrity of protective clothing or ensembles, particularly areas of the clothing or ensembles that cannot be directly assessed by this test method, such as interface areas between different items of clothing and equipment.

1.1 This test method is used to test specimens of protective clothing materials, assemblies such as seams and closures, or interfaces used in the construction of protective clothing. The resistance to visible penetration of the test liquid is determined with the liquid in continuous contact with the normally outside (exterior) surface of the test specimen.

1.2 This test method includes different procedures for maintaining the liquid in contact with the test specimen in terms of the length of exposure and the pressure applied. Suggestions are provided for how to select an appropriate procedure for liquid contact.

1.3 In some cases, significant amounts of hazardous materials will permeate specimens that pass the penetration tests. For more sensitive analyses, use either Test Method F739 or F1383 to determine permeation.

1.4 This test method does not address penetration of vapors through protective clothing materials.

1.5 This test method is not applicable to non-planar protective clothing materials, interfaces, or assemblies such as the fingertips or crotch areas of gloves, which are possible failure points.

1.6 This test method does not address the liquid penetration resistance of full protective clothing items or ensembles. Use Test Method F1359 for this purpose.

1.7 The values as stated in inch-pound units are to be regarded as the standard. The values in parentheses are for information only.

1.8 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. 1.9 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.