Patent ID: 8353418

Claim:
A pressure relief cap comprising: a body defining an attachment structure configured to sealingly engage with a container; a vent passage selectively providing fluid communication through the pressure relief cap between an interior of the pressure relief cap and an exterior of the pressure relief cap; a two-way pressure relief valve located along the vent passage and 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 actuable from the exterior of the pressure relief cap to open the two-way pressure relief valve; and a plug positioned along the vent passage in series with the two-way pressure relief valve, the plug being movable between a first position, in which the vent passage is open between the two-way pressure relief valve and the exterior of the pressure relief 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 pressure relief cap.