An enclosure for a power supply is provided. An aspect includes a first compartment and a second compartment located adjacent to the first compartment. Another aspect includes an intermediate pressure relief flap located inside the enclosure in between the first compartment and the second compartment, and a top pressure relief flap located on an external surface of the second compartment. Another aspect includes the intermediate pressure relief flap and the top pressure relief flap configured to be closed in the absence of an arc fault in the enclosure, and the intermediate pressure relief flap and the top pressure relief flap configured to open based on the presence of the arc fault in the enclosure, such that plasma from the arc fault vents from the first compartment into the second compartment via the opened intermediate pressure relief flap and out of the second compartment via the opened top pressure relief flap.