4.1 There are a large number of geomembrane types and seaming techniques. This guide is intended to help practitioners select the appropriate seam test methods for their material.

4.2 Geomembranes are relatively impermeable planar materials sheets that are shipped either as rolls or folded panels. The panels may be seamed in a factory or in the field. This guide provides geomembrane users with the most appropriate seam evaluation techniques for the most common geomembrane materials available on the market.

4.3 Some type of geomembrane may not be listed and some seam evaluation techniques may offer a good performance with a given material although this may not be indicated on Table 1. Users who are aware of this situation are invited to contact ASTM to propose an update of this guide.

Note 1: This type of test not commonly performed on this type of material, but it can be performed if desired.

Note 2: While Test Method D6392 was originally developed for non-reinforced geomembranes, it is standard practice for some manufacturers, fabricators, designers, and installers to use this method for reinforced products. However, a new standard test method is being worked on in D35.10 for seam evaluation of reinforced geomembranes, which shall be preferred to Test Method D6392 as soon as it is available.

Note 3: Only provides evaluation of seam continuity, but not seam strength.

Note 4: May not be applicable to very flexible geomembranes, especially thinner ones, that will highly deform into the vacuum box.

Note 5: There are some experiences with air lance on HDPE geomembrane seams for hole detection, although this is not common practice.

Note 6: Typically applicable to materials that are 1.0 mm and thinner.

Note 7: When applicable.

Note 8: Applicable to dual track seam only.

Note 9: Not applicable to extrusion fillet.

Note 10: Applicable to factory seams only.

Note 11: Refer to Guide D6747.

4.4 The relevance of a seaming technique within a particular engineering context is beyond the scope of this guide.