Building wiring is the electrical wiring and associated devices such as switches, meters and light fittings used in buildings or other structures.Electrical wiring uses insulated conductors. Wires and cables are rated by the circuit voltage, temperature and environmental conditions (moisture, sunlight, oil, chemicals) in which they can be used, and their maximum current.
Wiring safety codes are intended to protect people and property from electrical shock and fire hazards.
Regulations may be established by city, county, provincial/state or national legislation, usually by adopting a model code (with or without local amendments) produced by a technical standards-setting organisation, or by a national standard electrical code. Electrical codes arose in the 1880s with the commercial introduction of electrical power.
Many conflicting standards existed for the selection of wire sizes and other design rules for electrical installations. The first electrical codes in the United States originated in New York in 1881 to regulate installations of electric lighting.
Since 1897 the US National Fire Protection Association, a private non-profit association formed by insurance companies, has published the National Electrical Code (NEC).
States, counties or cities often include the NEC in their local building codes by reference along with local differences.
The NEC is modified every three years.It is a consensus code considering suggestions from interested parties. The proposals are studied by committees of engineers, tradesmen, manufacturer representatives, fire fighters and other invitees. Since 1927, the Canadian Standards Association (CSA) has produced the Canadian Safety Standard for Electrical Installations, which is the basis for provincial electrical codes.
The CSA also produces the Canadian Electrical Code, the 2006 edition of which references IEC 60364 (Electrical Installations for Buildings) and states that the code addresses the fundamental principles of electrical protection in Section 131.The Canadian code reprints Chapter 13 of IEC 60364, but there are no numerical criteria listed in that chapter to assess the adequacy of any electrical installation. Although the US and Canadian national standards deal with the same physical phenomena and broadly similar objectives, they differ occasionally in technical detail. As part of the North American Free Trade Agreement (NAFTA) program, US and Canadian standards are slowly converging toward each other, in a process known as harmonisation. In Germany, DKE (the German Commission for Electrical, Electronic and Information Technologies of DIN and VDE) is the organisation responsible for the promulgation of electrical standards and safety specifications. DIN VDE 0100 is the German wiring regulations document harmonised with IEC 60364. In the United Kingdom, wiring installations are regulated by the Institution of Engineering and Technology Requirements for Electrical Installations: IEE Wiring Regulations, BS 7671: 2008, which are harmonised with IEC 60364. The 17th edition (issued in January 2008) includes new sections for microgeneration and solar photovoltaic systems.
Neither is it designed for field use by electrical tradesmen and inspectors for testing compliance with national wiring standards.
In North America, the American Wire Gauge standard for wire sizes is used.
In such cases it may refer to an electrical emergency, which most often work electricians with high seniority and professional experience in the repair of different faults.