Embodiments of the present disclosure are directed toward a pressure vacuum relief valve and a seal assembly of the pressure vacuum relief valve. The seal assembly includes a ribbed substrate disposed against a flanged seat of the pressure vacuum relief valve. The ribbed substrate includes ribs extending from a base of the ribbed substrate. The seal assembly also includes a pallet coupled to and disposed below the ribbed substrate. The pallet includes a top ring, a bottom ring, and a flexible diaphragm captured between the top ring and the bottom ring. The flexible diaphragm of the pallet is configured to seal against the ribbed substrate in a sealed position. The pallet and ribbed substrate are configured to move together away from the flanged seat when a pressure on a sealed side of the pressure vacuum relief valve exceeds a maximum pressure threshold. The pallet is also configured to pivot open at an angle relative to the sealed position of the pallet when the pressure on the sealed side of the pressure vacuum relief valve falls below a minimum pressure threshold.