Abstract: The pressure relief assembly has a valve body constructed of breathable porous plastic. The valve body has an outer perimetric surface defining a detent mating surface and a sealing surface configured to form a seal around a valve opening. A first detent has a detent engagement surface configured to releasably engage the detent mating surface. The first detent is configured to release the valve body upon a minimum pressure differential across the valve body. The first detent is configured to extent laterally outward from the detent mating surface. The pressure relief assembly has a frame having a coupling structure configured to couple to an enclosure. The pressure relief assembly has a valve mounting surface and a valve opening within the valve mounting surface, where the valve body is sealably disposed on the valve mounting surface across the valve opening.