Patent attributes
A pressure relief cap engageable with a container includes a vent passage between an interior of the cap and an exterior of the cap. A two-way pressure relief valve is located along the vent passage and is configured to open automatically in response to a positive net interior pressure exceeding a first threshold pressure and in response to a negative net interior pressure exceeding a second threshold pressure. A manual actuator is actuable from the exterior of the cap to open the two-way pressure relief valve. A plug is positioned along the vent passage in series with the two-way pressure relief valve, movable between a first position in which the vent passage is open between the two-way pressure relief valve and the exterior of the cap and a second position in which the plug closes the vent passage between the two-way pressure relief valve and the exterior of the cap.

