Method for testing integrity of a filter medium

An assembly for testing the integrity of a porous filter medium, said assembly comprising:

• one or more housings, each of said one or more housings comprising an interior separated into an upstream portion and a downstream portion;
• said one or more housings further comprising an inlet in fluid connection with the upstream portion and an outlet in fluid connection with the downstream portion of the interior,
• a porous filter medium separating the interior of a housing into said upstream portion at an upstream side of the porous filter medium and said downstream portion at a downstream side of the porous filter medium, said porous filter medium being provided in the form of one or more filter elements, said porous filter medium having a predefined bubble point;
• a gas-filled testing volume fluidly connectable to the downstream portion(s) of the one or more housings;
• wherein the assembly comprises a valve for fluidly connecting and disconnecting the gas-filled testing volume to the downstream portion of each of the one or more housings;
• a means for measuring a pressure of a gas within the gas-filled testing volume within a predetermined time;
• a filtrate conduit providing a flow path extending from the outlet of the interior of each the one or more housings to the gas-filled testing volume, said filtrate conduit comprising a closable end remote from the outlet;
• a pressure source suitable for increasing a pressure of a testing gas in the upstream portion of the one or more housings up to a predetermined testing differential pressure and maintaining the pressure at a predetermined pressure level, said predetermined testing differential pressure being lower than the predefined bubble point of the porous filter medium, and
• a means for comparing a measured pressure of the gas within the gas-filled testing volume within the predetermined time to a pressure obtained within the predetermined time when testing a non-defective porous filter medium, wherein in case the measured pressure of the gas within the gas-filled testing volume is higher than a predefined pressure provided for the non-defective porous filter medium in a specific filtration environment, the porous filter medium under test is qualified as defective.

An assembly for testing the integrity of a porous filter medium, said assembly comprising:

• one or more housings, each of said one or more housings comprising an interior separated into an upstream portion and a downstream portion;
• said one or more housings further comprising an inlet in fluid connection with the upstream portion and an outlet in fluid connection with the downstream portion of the interior,
• a porous filter medium separating the interior of a housing into said upstream portion at an upstream side of the porous filter medium and said downstream portion at a downstream side of the porous filter medium, said porous filter medium being provided in the form of one or more filter elements, said porous filter medium having a predefmed bubble point;
• a gas-filled testing volume fluidly connectable to the downstream portion(s) of the one or more housings;
• a means for measuring a pressure of a gas within the gas-filled testing volume within a predetermined time;
• a filtrate conduit providing a flow path extending from the outlet of the interior of each the one or more housings to the gas-filled testing volume, said filtrate conduit comprising a closable end remote from the outlet;
• wherein the gas-filled testing volume is provided in a portion of said filtrate conduit, said filtrate conduit portion being delimited by an upstream valve and a downstream valve defming in between the gas-filled testing volume;
• a pressure source suitable for increasing a pressure of a testing gas in the upstream portion of the one or more housings up to a predetermined testing differential pressure and maintaining the pressure at a predetermined pressure level, said predetermined testing differential pressure being lower than the predefmed bubble point of the porous filter medium, and
• a means for comparing a measured pressure of the gas within the gas-filled testing volume within the predetermined time to a pressure obtained within the predetermined time when testing a non-defective porous filter medium, wherein in case the measured pressure of the gas within the gas-filled testing volume is higher than a predefined pressure provided for the non-defective porous filter medium in a specific filtration environment, the porous filter medium under test is qualified as defective.

An assembly for testing the integrity of a porous filter medium, said assembly comprising:

• one or more housings, each of said one or more housings comprising an interior separated into an upstream portion and a downstream portion;
• said one or more housings further comprising an inlet in fluid connection with the upstream portion and an outlet in fluid connection with the downstream portion of the interior,
• a porous filter medium separating the interior of a housing into said upstream portion at an upstream side of the porous filter medium and said downstream portion at a downstream side of the porous filter medium, said porous filter medium being provided in the form of one or more filter elements, said porous filter medium having a predefmed bubble point;
• a gas-filled testing volume fluidly connectable to the downstream portion(s) of the one or more housings;
• a means for measuring a pressure of a gas within the gas-filled testing volume within a predetermined time;
• a filtrate conduit providing a flow path extending from the outlet of the interior of each the one or more housings to the gas-filled testing volume, said filtrate conduit comprising a closable end remote from the outlet;
• a pressure source suitable for increasing a pressure of a testing gas in the upstream portion of the one or more housings up to a predetermined testing differential pressure and maintaining the pressure at a predetermined pressure level, said predetermined testing differential pressure being lower than the predefmed bubble point of the porous filter medium,
• a means for comparing a measured pressure of the gas within the gas-filled testing volume within the predetermined time to a pressure obtained within the predetermined time when testing a non-defective porous filter medium, wherein in case the measured pressure of the gas within the gas-filled testing volume is higher than a predefined pressure provided for the non-defective porous filter medium in a specific filtration environment, the porous filter medium under test is qualified as defective, and,
• wherein said gas-filled volume is selected such that, when a filter medium is tested having a bubble point corresponding to the predefmed bubble point, a pressure increase of the gas within the gas-filled testing volume of about 100 mbar is obtained within a period of 10 minutes.