Explosion Proof Distribution Box & Electrical Enclosures are certified for Class I, Division 1 and Class II, Division 1. You need to check if the enclosure fits the danger level and protection type. For example, you might need Ex d for flameproof or Ex i for safe designs. The. The Code of Federal Regulations (CFR) is the official legal print publication containing the codification of the general and permanent rules published in the Federal Register by the departments and agencies of the Federal Government. Ex Industries (exindustries) is a global supplier of advanced hazardous area. “Explosion protection” refers to techniques used to minimize the potential for electrical and electronic equipment to create an ignition while operating in a hazardous location (HAZLOC).