This part of IEC 60670 applies to boxes, enclosures and parts of enclosures (hereafter called "boxes" and "enclosures") for electrical accessories with a rated voltage not exceeding 1 000 V a. intended for household or similar fixed electrical installations . The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes International Standards for all electrical, electronic and related technologies. The technical content of IEC publications is kept under constant review by the IEC. Please make sure. Design requirements for low voltage distribution boxes cover NEC, IEC, and safety standards to ensure reliable, compliant electrical installations. What is Power. It's not you, it's us. An error has occurred and we're working to fix the problem.