A valve assembly (12) includes a first housing (22), a diaphragm member (24) having a plurality of individually pivotable sealing members (50), and a second housing (26) coupled to the end of the first housing over the diaphragm member. The second housing has a plurality of ports (78) spaced about the second member. The diaphragm member is structured to actuate between (i) a first state wherein the sealing members substantially seal the end of the first housing responsive to a pressure within the first housing being below a certain level, each of the ports being open in the first state, and (ii) a second state wherein the sealing members pivot away from and do not substantially seal the end of the first housing responsive to a pressure in the first housing being at or above the certain level, each sealing member substantially sealing a respective one of the ports in the second state.