Venting means

Claim 1

A filtration system for the filtration of blood or blood components comprising: a collapsible reservoir which contains the blood or blood components to be filtered; a receiving container for receiving filtered blood or blood components; a transfer line in communication with said collapsible reservoir and with said receiving container; a filter capable of filtering said blood or said blood components carried in said transfer line between said reservoir and said receiving container; and venting means in said transfer line downstream of said filter and upstream of said receiving container, said venting means comprising: (a) a housing; (b) a first microporous membrane positioned in said housing to the inward side of said venting means in communication with said transfer line, said first microporous membrane being liquid-wettable by the liquid to be transferred in said filtration system; and (c) a second microporous membrane to the outward side of said venting means, said second microporous membrane capable of permitting gas to pass therethrough, said membranes arranged to permit gas to be vented from said venting means while said first microporous membrane remains unwetted with liquid, and to permit said venting means to be sealed when said first microporous membrane is wetted with liquid.

Claim 9

A method for priming a liquid transfer system wherein said system comprises a collapsible reservoir which contains a liquid and a liquid transfer line in communication with said collapsible reservoir, said method comprising: collapsing the collapsible reservoir to discharge liquid from said reservoir to said liquid transfer line; and maintaining sufficient pressure on said collapsible reservoir to cause the liquid to flow through said line toward the terminal end of the line causing any gas in the line to contact venting means in said liquid transfer line and allowing gas to pass from said line, said venting means comprising a first microporous membrane wettable by the liquid and a second microporous membrane capable of passing said gas, said first and second membranes positioned relative to each other so that gas or liquid first contacts said first membrane, said first microporous membrane permitting the passage of gas until it is wetted by said liquid, whereupon it is no longer capable of passing gas therethrough.

Claim 10

A method for priming a liquid transfer system wherein said system comprises a collapsible reservoir which contains a liquid and a liquid transfer line in communication with said collapsible reservoir, said method comprising: collapsing the collapsible reservoir to discharge liquid from said reservoir to said liquid transfer line; and maintaining sufficient pressure on said collapsible reservoir to cause the liquid to flow through said line toward the terminal end of the line causing any gas in the line to contact venting means in said liquid transfer line and allowing gas to pass from said line, said venting means comprising a first microporous membrane wettable by the liquid and a second microporous membrane capable of passing said gas, said first and second membranes positioned relative to each other so that gas or liquid first contacts said first membrane, said first microporous membrane permitting the passage of gas until it is wetted by said liquid, whereupon it is no longer capable of passing gas therethrough.

Claim 21

A method of preserving the sterility of a closed liquid transfer system wherein said system has a sterile internal environment, and said system comprises a collapsible reservoir which contains a liquid, and a liquid transfer line in communication with said collapsible reservoir, said method comprising: collapsing the collapsible reservoir to discharge liquid from said reservoir to said liquid transfer line; and maintaining sufficient pressure on said collapsible reservoir to cause the liquid to flow through said line toward the terminal end of the line causing any gas in the line to contact venting means in said liquid transfer line and allowing gas to pass from said line, said venting means comprising a first microporous membrane wettable by the liquid and a second microporous membrane capable of passing said gas, said first and second membranes positioned relative to each other so that gas or liquid first contacts said first membrane, said first microporous membrane permitting the passage of gas until it is wetted by said liquid, whereupon it is no longer capable of passing gas therethrough.

Claim 22

A method of preserving the sterility of a closed liquid transfer system wherein said system has a sterile internal environment, and said system comprises a collapsible reservoir which contains a liquid, and a liquid transfer line in communication with said collapsible reservoir, said method comprising: collapsing the collapsible reservoir to discharge liquid from said reservoir to said liquid transfer line; and maintaining sufficient pressure on said collapsible reservoir to cause the liquid to flow through said line toward the terminal end of the line causing any gas in the line to contact venting means in said liquid transfer line and allowing gas to pass from said line, said venting means comprising a first microporous membrane wettable by the liquid and a second microporous membrane capable of passing said gas, said first and second membranes positioned relative to each other so that gas or liquid first contacts said first membrane, said first microporous membrane permitting the passage of gas until it is wetted by said liquid, whereupon it is no longer capable of passing gas therethrough.