A shut-off valve is provided for use in a suction canister. The shut-off valve comprises a valve portion comprising a valve body having at least one side wall and an end wall collectively defining a valve interior. The valve body has an open end configured to allow fluid communication between the valve interior and an outlet port of the canister. The valve body walls comprise a porous plastic material and a moisture-reactive material adapted to expand on contact with liquid and reduce or eliminate the flow path through the porous plastic material. The shut-off valve further comprises a filter portion covering at least a portion of an exterior surface of the valve body. The filter portion comprises a fiber filter medium comprising a plurality of fibers collectively defining a tortuous fluid flow path through the fiber filter medium.
