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.