Underground electrical and communication conduit should be impervious to groundwater in order to prevent damage to conductors and utility vaults. The bladder test described in this test method may be used to qualify potential gasketed conduit systems by indicating whether the joint system will prevent water infiltration.

This test method can be used to qualify joints for plastic underground conduits using flexible elastomeric seals. However, it should not be assumed that a joint system that passes this test method will be able to seal under cases of misinstallation or abuse, or both.

This test method covers all of the following gasketed conduit types: encased burial (EB) excluding EB20, direct burial (DB), telecommunications, cable television, and Schedule 40 conduit and Schedule 80 conduit. Trade sizes covered are 2-in. nominal size and larger. (See UL 651; NEMA TC-2, TC-6, and TC 8; and Specification F 512.)

This test method also covers fittings that are intended for use with the conduit types described in 3.3 and which use flexible elastomeric seals.