

The current version is BS 7671:2018 (the 18th Edition) issued in 2018 and came into effect from 1 January 2019.

The standard takes account of the technical substance of agreements reached in CENELEC. It did not become a recognized British Standard until the publication of the 16th edition in 1992. The frequencies covered for AC are 50 Hz, 60 Hz, and 400 Hz, used in the UK for houses, offices, and commerce. The standard therefore covers the Extra Low Voltage (ELV) range (0-50V AC, 0-125V DC), and the Low Voltage (LV) range (50-1000V AC, 125-1500V DC). In general, BS 7671 applies to circuits supplied at nominal voltages (Uo) up to and including 1000 volts AC or 1500 volts DC. IET Wiring Regulations", informally called in the UK electrical community "The Regs", is the national standard in the United Kingdom for electrical installation and the safety of electrical wiring in domestic, commercial, industrial, and other buildings, also in special installations and locations, such as marinas or caravan parks and medical locations British Standard BS 7671 "Requirements for Electrical Installations.
