A test methodology for studying liquid penetration of barrier materials

A test apparatus for determining pressure at:liquid breakthrough as a funct ion of how rate is designed and constructed. The method reveals that as flo w rate increases, the volume of material penetrated by the liquid increases . In addition, pressure at penetration does not strongly depend on flow rat e and even decreases with flow rate for some materials. Peak pressure and d istance to peak increase with flow rate. Steady-state pressure increases wi th flow rate but not according to the Poiseuille equation, as would be expe cted. This test method permits comparison of materials in terms of barrier performance.