This test is intended to assure that a fluid-blocked fiber optic cable is filled and flooded (or otherwise appropriately fluid-blocked with, for example, super-absorbents) sufficiently to restrict or otherwise prohibit the penetration and flow of water or other fluid within the core or along the cable sheath interfaces, or both. The test is designed primarily for testing filled fiber optic telecommunications cables intended for installations in underground ducts or directly buried, where ground water pressures are normally encountered; however, this test method can be used to assure or to evaluate fluid penetration integrity in other environments by specifying appropriate fluid(s), test length(s), pressure (s), allowable flow rate(s), etc., in the cable Detail Specification.(Footnote 1)

NOTE: Fiber optic cables, like many products, are available in a multiplicity of designs, and not all cable designs will perform equally well in this test (nor are they necessarily intended to be equal). Different cable sheath designs may provide fluid paths, to some degree, outside of the cable core, but such paths may be no problem in a particular application. Although applications for fluid-blocked cables generally require resistance to fluid penetration in both the core and in all sheath interfaces (or interstices), this may not always be the case.

It is the responsibility of the writer of the Detail Specification for the fiber optic cable product to determine if FOTP-82 should be a required test, how that test should be imposed (special sample preparation, etc.), and what the particular performance requirements should be (amount of fluid flow permitted, retest allowance, etc.)

Footnote 1 - This method is similar to the water penetration test for telecommunications cable appearing in ASTM D 4565.