Standard Practice for Nondestructive Testing of Geomembrane Seams Using the Spark Test

1.1 This practice covers the nondestructive testing of field seams in geomembranes using the spark test. A suspect area is indicated by the generation of a spark. The test is applicable to seams made by the extrusion method, seams made by using welding tape (a strip of the same type of material as the geomembrane, that is welded over adjacent sections of geomembrane to create a seam), or seams where it is practical to insert a conductive material in the seam just prior to or during fabrication.

1.2 The spark test may produce an electrical spark and therefore can only be used where an electrical spark would not create a hazard.

1.3 Unless the voltages and distances prescribed are carefully adhered to, a “false positive” indication may result. This false positive occurs when the arc distance is too large for the voltage applied at the time and conditions of testing.

1.4 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.

1.5 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.

1.6 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.