An electrical enclosure including a plurality of walls (4, 6, 8), the electrical enclosure comprising: at least one compartment defined, at least in part, by the plurality of walls (4, 6, 8); at least one ventilation opening (90, 92) formed in one of the plurality of walls (4, 6, 8), the ventilation opening (90, 92) includes a first ventilation opening and a second ventilation opening and providing a flow path from the at least one compartment; and at least one closure (94, 96) provided on the one of the plurality of walls (4, 6, 8) at the at least one ventilation opening (90, 92), the at least one closure (94, 96) being responsive to a pressure wave to selectively close the at least one ventilation opening (90, 92) and re-open the at least one ventilation opening (90, 92) after the pressure wave has passed from the electrical enclosure, wherein the plurality of walls (4, 6, 8) includes a first wall, second wall, and third wall, and the at least one closure (94, 96) includes a first end (104, 130), a second end (105, 131), and an intermediate portion (110, 136) extending between the first end (104, 130) and the second end (105, 131), characterized in that the first end (104, 130) being pivotally mounted to the third wall, the at least one closure includes a center of gravity established toward the first end, the at least one closure arranged at the first ventilation opening being responsive to gravity to pivot away from the third wall at the first end, and the at least one closure includes a center of gravity established toward the second end, the at least one closure arranged at the second ventilation opening being responsive to gravity to pivot away from the third wall at the first end. at least one compartment defined, at least in part, by the plurality of walls (4, 6, 8); at least one ventilation opening (90, 92) formed in one of the plurality of walls (4, 6, 8), the ventilation opening (90, 92) includes a first ventilation opening and a second ventilation opening and providing a flow path from the at least one compartment; and at least one closure (94, 96) provided on the one of the plurality of walls (4, 6, 8) at the at least one ventilation opening (90, 92), the at least one closure (94, 96) being responsive to a pressure wave to selectively close the at least one ventilation opening (90, 92) and re-open the at least one ventilation opening (90, 92) after the pressure wave has passed from the electrical enclosure, wherein the plurality of walls (4, 6, 8) includes a first wall, second wall, and third wall, and the at least one closure (94, 96) includes a first end (104, 130), a second end (105, 131), and an intermediate portion (110, 136) extending between the first end (104, 130) and the second end (105, 131), characterized in that the first end (104, 130) being pivotally mounted to the third wall, the at least one closure includes a center of gravity established toward the first end, the at least one closure arranged at the first ventilation opening being responsive to gravity to pivot away from the third wall at the first end, and the at least one closure includes a center of gravity established toward the second end, the at least one closure arranged at the second ventilation opening being responsive to gravity to pivot away from the third wall at the first end.