Integrity test method for porous filters
View Patent ↗An improved method of testing the integrity of a porous filter is provided. The test method is an improvement over a gas-liquid diffusion test wherein the improvement comprises providing a conduit downstream of the filter and filling the conduit with a liquid, the conduit having a length to cross sectional area ratio selected to substantially resist diffusive flow of the gas through the liquid downstream of the filter material.
1. A method for testing the integrity of a filter comprising porous filter material having a bubble point, the method comprising:
providing a filter fixture with an inlet for fluid flow and outlet for fluid flow;
installing said porous filter in the filter fixture between the inlet and the outlet;
wetting the porous filter material to fill the pores of the material with a wetting liquid;
filling the filter fixture between the wetted, porous filter media and the fluid outlet with a liquid;
pressurizing the filter fixture by providing gas at the fluid inlet of the filter fixture at a pressure lower than the bubble point of the wetted, porous filter;
weighing the liquid displaced from the filter fixture responsive to the pressurizing of the filter fixture; and
calculating the gas flow from the displaced liquid volume.