The IEC (International Electrotechnical Commission) and BS 7671 (British Standard for Electrical Installations) both provide essential requirements for electrical installations, including those for fuse boards like garage unit, consumer unit and distribution board. However, the key to a safe and reliable system lies in proper installation. If it's done poorly, you risk short circuits, fire hazards, or system failure. While the IEC 60364 standard. What is a Distribution Box? A distribution box, or DB box, is a circuit breaker enclosure. Whether it's a home, office, or factory. Electrical distribution boxes are used in commercial and residential buildings and are part of the electrical system, also known as switchboards.