Knowledge gaps and test method development are drivers for polymers being tested in laboratory-scale manifolds mimicking infrastructure pressures and temperatures. In such operations, polymers often first see helium and argon used as purge gases and leak detection gases in the manifold even before H2  exposure.

Controlled decompression rates at controlled temperatures
Construction of a one-of-a-kind High pressure Cycling Manifold

This study attempts to isolate the effect of these leak detection gases from actual hydrogen effects on polymer properties. Effects on polymers due to He and Ar high pressures, times of exposure, penetrant gas type and molecular size, relative diffusion and permeations rates are important to isolate from those due to hydrogen. Cumulative damage in polymers due to exposure to high pressure H2, argon and helium. Effects of rapid gas decompression due to fast uncontrolled depressurization rates.