BS 7671

Last updated

British Standard BS 7671 "Requirements for Electrical Installations. 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 systems [1]

Contents

SCOPE of BS 7671

The regulations in BS7671 applies to the design, selection, erection and verification of electrical installations within;

  1. residential properties
  2. commercial properties
  3. public premises
  4. industrial premises
  5. prefabricated building
  6. low voltage generating sets
  7. highway equipment and street furniture
  8. locations containing a bath or shower
  9. rooms or cabins that contain a sauna
  10. swimming pools and other basins
  11. construction and demolition sites
  12. agricultural and horticultural premises
  13. caravan/camping parks and similar locations
  14. marinas and similar locations
  15. medical locations
  16. exhibitions, shows and stands
  17. Solar photovoltaic (PV) power supply systems (Domestic and commercial)
  18. outdoor lighting installations
  19. extra-low voltage lighting
  20. mobile and transportable units
  21. caravans and motor caravans
  22. temporary installations for structures, amusement devices/booths at fairgrounds, amusement parks, circuses and professional stage and broadcast applications
  23. operating and maintenance gangways
  24. floor and ceiling heating systems
  25. onshore units of electrical shore connections for inland navigation vessels.

Exclusions from the scope of BS 7671 are the following.

  1. systems for the distribution of electricity to the public other than prosumer's installations covered by Chapter 82
  2. Railway traction equipment, rolling stock and signalling equipment
  3. Equipment of motor vehicles, except those to which the requirements of the Regulations concerning caravans or other types of mobile unit are applicable.
  4. Equipment on board ships covered by BS 8450, BS EN 60092-507, BS EN ISO 13297 or BS EN ISO 10133
  5. Equipment of mobile or fixed offshore installations.
  6. Equipment within and aircraft.
  7. Those aspects of mines covered by Statutory Regulations
  8. Radio interference suppression equipment, except so far as it affects safety of the electrical installation.
  9. Lightning protection systems for buildings and structures covered by BS EN 62305.
  10. Those aspects of Lift Installations covered by relevant parts of BS 5655 and BS EN 81 and those aspects of escalator or moving walkway installations covered by relevant parts of BS 5656 and BS EN 115.
  11. Electrical equipment of machines covered by BS EN 60204.
  12. Electric fences covered by BS EN 60335-2-76
  13. The DC side of cathodic protection systems complying with the relevant part(s) of BS EN 12696, BS EN 12954, BS EN ISO 13174, BS EN 13636 and BS EN 14505.

BS 7671 only covers electrical systems that the IET defines as those covered by the following.

Part 2 - Definitions the voltages covered by BS7671 are defined thus.

Voltage, nominal (U0). The voltage by which an installation (or part of an installation) is designated and the following ranges of nominal voltage (rms values for AC) are defined


It did not become a recognized British Standard until after the publication of the 16th edition in 1992. The standard takes account of the technical substance of agreements reached in CENELEC. [2]

The current version is BS 7671:2018+A2:2022 (the 18th Edition) issued in 2022, and came into effect from 28 March 2022 (the previous version BS 7671:2018+A1:2020 being withdrawn on 27 September 2022). BS 7671 is also used as a national standard by Mauritius, St Lucia, Saint Vincent and the Grenadines, Sierra Leone, Singapore, Sri Lanka, Trinidad and Tobago, Uganda, Cyprus, and several other countries, which base their wiring regulations on BS 7671.

Compilation and publication

The standard is maintained by the Joint IET/BSI Technical Committee JPEL/64, the UK National Committee for Wiring Regulations, and published jointly by the IET (formerly IEE) and BSI. Although the IET and BSI are non-governmental organisations and the Wiring Regulations are non-statutory, they are referenced in several UK statutory instruments, and in most cases, for practical purposes, have legal force as the appropriate method of electric wiring. [3]

The BSI (British Standards Institute) publishes numerous titles concerning acceptable standards of design/safety/quality across different fields.

History of BS 7671 and predecessor standards

The first edition was published in 1882 as the "Rules and Regulations for the Prevention of Fire Risks arising from Electric Lighting." The title became "General Rules recommended for Wiring for the Supply of Electrical Energy" with the third edition in 1897, "Wiring Rules" with the fifth edition of 1907, and settled at "Regulations for the Electrical Equipment of Buildings" with the eighth edition in 1924.

Since the 15th edition (1981), these regulations have closely followed the corresponding international standard IEC 60364. In 1992, the IEE Wiring Regulations became British Standard BS 7671 so that the legal enforcement of their requirements was easier both with regard to the Electricity at Work regulations and from an international point of view. [4] They are now treated similar to other British Standards. BS 7671 has converged towards (and is largely based on) the European Committee for Electrotechnical Standardization (CENELEC) harmonisation documents, and therefore is technically very similar to the current wiring regulations of other European countries.

1st Edition

"Rules and Regulations for the Prevention of Fire Risks arising from Electric Lighting." - Two core cable, line and neutral, no earth. The protection was a re-wirable fuse.

17th Edition

A bookstore selling the 17th Edition in 2008 Sign advising that the IEE Electrical Wiring Regulations 17th Edition is now kept behind tills.jpg
A bookstore selling the 17th Edition in 2008

The 17th edition, released in January 2008 and amended in 2011 ("Amendment 1"), 2013 ("Amendment 2") and January 2015 ("Amendment 3") became effective for all installations designed after 1 July 2008. [5] One of the more significant changes is (chapter 41) that 30 mA RCDs will be required for socket outlets that are for use by ordinary persons and are intended for general use. This improves the level of protection against electrical shock in the UK to a level comparable to that in other EU countries, where the residual current breaker is usually found in the main- or group central. The 17th edition and its amendments incorporated new sections relating to microgeneration and solar photovoltaic systems, non-combustible consumer units, RCDs, and breakers (including high resilience breaker layout).

  • As originally published highlights - RCDs required for most outlets
  • Amendment 1 highlights - high resilience consumer units
  • Amendment 2 highlights - electric vehicle charging added, earlier change incorporated for medical locations [6]
  • Amendment 3 highlights - non-combustible consumer units/enclosures [7]

18th Edition

Timeline

DateEdition / changeInformation
18821st EditionTitled ‘Rules and Regulations for the prevention of Fire Risks Arising from Electric Lighting’, and known as the "Wiring Rules"
18882nd EditionTitled 'Wiring Rules & Regulations in Buildings
18973rd EditionTitled ‘General Rules recommended for Wiring for the Supply of Electrical Energy’
19034th Editionissued as IEE Wiring Regulations, called ‘Wiring Rules’
19075th EditionIssued as IEE Wiring Regulations
19116th EditionIssued as IEE Wiring Regulations
19167th EditionIssued as IEE Wiring Regulations
19248th EditionIssued as IEE Wiring Regulations ‘Regulations for the Electrical Equipment of Buildings’
19279th EditionIssued as IEE Wiring Regulations
193410th EditionIssued as IEE Wiring Regulations 3 phase colours red, white and green, neutral or earth black.
193911th EditionIssued as IEE Wiring Regulations. Revised in 1943, reprint with minor amendments in 1945, supplement in 1946, further revised in 1948 last edition to allow sockets in a bathroom. 3 phase colours red, white and blue, Black for neutral or earth.
195012th EditionIssued as IEE Wiring Regulations. Supplement issued 1954 First mention of PVC insulated cables.

3 phase colours red white and blue, Black for neutral or earth in fixed wiring. Green earth in flex.

195513th EditionIssued as IEE Wiring Regulations. Reprinted in 1958, 1961, 1962, 1964
196614th EditionIssued as IEE Wiring Regulations. (adds earthing on lighting circuits) Reprinted in 1968, 1969, 1969 again (metric units[ verification needed ]), 1970 (in metric units), 1972, 1973, 1974, 1976
198115th EditionIssued as IEE Wiring Regulations. (Possibly reprinted 1983, 1984, 1986 amendment to remove voltage operated earth leakage circuit breakers), 1987, 1988?[ verification needed ])
199116th EditionIssued as IEE Wiring Regulations. Reprinted with amendments 1992, 1994, 1997, 2000, 2001, 2004
1992BSI adopts as a standardWiring Regulations adopted by the British Standards Institute as BS 7671
1992LegislationElectricity at Work Regulations come fully into effect in Northern Ireland
2004Incorporated into building regulationsPart P of the Building Regulations ("Requirements for Electrical Installations") comes into force, covering legal requirements for electrical installations in England and Wales. The guidance in the Approved Documents refers to BS 7671 as being one way to achieve compliance. The version in force when the law came into effect was the 16th edition, BS 7671:2001, as amended in 2002 and 2004 Amendment 2 (change of phase colours) .
200817th EditionAmended 2015 ("Amendment no. 3") metal consumer units.
201818th EditionIntroduced energy efficiency performance levels and the use of surge protection devices and arc fault detection devices. [8]

Amended February 2020 ("Amendment no. 1") Changes to rules on car charging.

Amended March 2022 ("Amendment no. 2") Current standard as of March 2022

See also

Related Research Articles

<span class="mw-page-title-main">British Standards</span> Standards produced by BSI Group

British Standards (BS) are the standards produced by the BSI Group which is incorporated under a royal charter and which is formally designated as the national standards body (NSB) for the UK. The BSI Group produces British Standards under the authority of the charter, which lays down as one of the BSI's objectives to:

Set up standards of quality for goods and services, and prepare and promote the general adoption of British Standards and schedules in connection therewith and from time to time to revise, alter and amend such standards and schedules as experience and circumstances require.

<span class="mw-page-title-main">Electrician</span> Tradesperson specializing in electrical wiring

An electrician is a tradesperson specializing in electrical wiring of buildings, transmission lines, stationary machines, and related equipment. Electricians may be employed in the installation of new electrical components or the maintenance and repair of existing electrical infrastructure. Electricians may also specialize in wiring ships, airplanes, and other mobile platforms, as well as data and cable lines.

<span class="mw-page-title-main">Residual-current device</span> Electrical safety device used in household wiring

A residual-current device (RCD), residual-current circuit breaker (RCCB) or ground fault circuit interrupter (GFCI) is an electrical safety device that interrupts an electrical circuit when the current passing through a conductor is not equal and opposite in both directions, therefore indicating an improper flow of current such as leakage current to ground or current flowing to another powered conductor. The device's purpose is to reduce the severity of injury caused by an electric shock. Injury from shock is limited to the time before the electrical circuit is interrupted, but the victim may also sustain further injury, e.g. by falling after receiving a shock. This type of circuit interrupter can not distinguish between current flowing though power carrying conductors that passes through a person from current that passes through electrical equipment and offer no protection when a person touches both conductors at the same time.

A distribution board is a component of an electricity supply system that divides an electrical power feed into subsidiary circuits while providing a protective fuse or circuit breaker for each circuit in a common enclosure. Normally, a main switch, and in recent boards, one or more residual-current devices (RCDs) or residual current breakers with overcurrent protection (RCBOs) are also incorporated.

In electricity supply design, a ring circuit is an electrical wiring technique in which sockets and the distribution point are connected in a ring. It is contrasted with the usual radial circuit, in which sockets and the distribution point are connected in a line with the distribution point at one end.

<span class="mw-page-title-main">Electrical wiring</span> Electrical installation of cabling

Electrical wiring is an electrical installation of cabling and associated devices such as switches, distribution boards, sockets, and light fittings in a structure.

Electrical wiring in the United Kingdom is commonly understood to be an electrical installation for operation by end users within domestic, commercial, industrial, and other buildings, and also in special installations and locations, such as marinas or caravan parks. It does not normally cover the transmission or distribution of electricity to them.

An earthing system or grounding system (US) connects specific parts of an electric power system with the ground, typically the Earth's conductive surface, for safety and functional purposes. The choice of earthing system can affect the safety and electromagnetic compatibility of the installation. Regulations for earthing systems vary among countries, though most follow the recommendations of the International Electrotechnical Commission (IEC). Regulations may identify special cases for earthing in mines, in patient care areas, or in hazardous areas of industrial plants.

IEC 60364Electrical Installations for Buildings is the International Electrotechnical Commission (IEC)'s international standard on electrical installations of buildings. This standard is an attempt to harmonize national wiring standards in an IEC standard and is published in the European Union by CENELEC as "HD 60364". The latest versions of many European wiring regulations follow the section structure of IEC 60364 very closely, but contain additional language to cater for historic national practice and to simplify field use and determination of compliance by electricians and inspectors. National codes and site guides are meant to attain the common objectives of IEC 60364, and provide rules in a form that allows for guidance of persons installing and inspecting electrical systems.

<span class="mw-page-title-main">Extra-low voltage</span> Electrical standard designed to protect against electric shock

Extra-low voltage (ELV) is an electricity supply voltage and is a part of the low-voltage band in a range which carries a low risk of dangerous electrical shock. There are various standards that define extra-low voltage. The International Electrotechnical Commission (IEC) and the UK IET define an ELV device or circuit as one in which the electrical potential between two conductors or between an electrical conductor and earth (ground) does not exceed 50 V AC or 120 V DC.

European Standards, sometimes called Euronorm, are technical standards which have been ratified by one of the three European Standards Organizations (ESO): European Committee for Standardization (CEN), European Committee for Electrotechnical Standardization (CENELEC), or European Telecommunications Standards Institute (ETSI). All ENs are designed and created by all standards organizations and interested parties through a transparent, open, and consensual process.

<span class="mw-page-title-main">Fireman's switch</span>

A fireman's switch is a specialized switch that allows firefighters to quickly disconnect power from high voltage devices that may pose a danger in the event of an emergency. According to the Institution of Electrical Engineers, any electrical device operating at over 1,000 Volts AC or 1,500 volts DC, must be equipped with the switch.

An electrical code is a set of regulations for the design and installation of electrical wiring in a building. The intention of a code is to provide standards to ensure electrical wiring systems that are safe for people and property.

In electrical engineering, low voltage is a relative term, the definition varying by context. Different definitions are used in electric power transmission and distribution compared with electronics design. Electrical safety codes define "low voltage" circuits that are exempt from the protection required at higher voltages. These definitions vary by country and specific codes or regulations.

<span class="mw-page-title-main">Portable appliance testing</span> Procedure in which electrical appliances are routinely checked for safety

In electrical safety testing, portable appliance testing is a process in the United Kingdom, Ireland, New Zealand and Australia by which electrical appliances are routinely checked for safety. The formal term for the process is "in-service inspection & testing of electrical equipment". Testing involves a visual inspection of the equipment and that any flexible power cables are in good condition, and also where required, verification of earthing (grounding) continuity, and a test of the soundness of insulation between the current carrying parts, and any exposed metal that may be touched. The formal limits for pass/fail of these electrical tests vary somewhat depending on the category of equipment being tested.

In electrical engineering, electrical safety testing is essential to make sure electrical products and installations are safe. To meet this goal, governments and various technical bodies have developed electrical safety standards. All countries have their own electrical safety standards that must be complied with. To meet to these standards, electrical products and installations must pass electrical safety tests.

In electrical power distribution, armoured cable usually means steel wire armoured cable (SWA) which is a hard-wearing power cable designed for the supply of mains electricity. It is one of a number of armoured electrical cables – which include 11 kV Cable and 33 kV Cable – and is found in underground systems, power networks and cable ducting.

NICEIC is one of several organisations which assesses the competence of businesses undertaking electrical work in the UK. NICEIC is one of several providers given Government approval to offer Competent Person Schemes in England and Wales to oversee electrical work within the scope of Part P of the Building Regulations.

<span class="mw-page-title-main">AC power plugs and sockets: British and related types</span> AC power plug type

Plugs and sockets for electrical appliances not hardwired to mains electricity originated in the United Kingdom in the 1870s and were initially two-pin designs. These were usually sold as a mating pair, but gradually de facto and then official standards arose to enable the interchange of compatible devices. British standards have proliferated throughout large parts of the former British Empire.

References

  1. BS7671 chapter 11 - scope
  2. BS7671: Preface
  3. "Regulatory Requirements" (PDF). p. 3.
  4. Electrician's guide to the 17th edition of the IEE wiring regulations. 3rd edition pub 2012 John Whitfield
  5. Geoff Cronshaw: The 17th edition: a brief overview Archived 3 September 2014 at the Wayback Machine . IEE Wiring Matters, Summer 2007.
  6. "IET launches Amendment 3 to BS 7671:2008". Voltimum UK. Retrieved 1 March 2018.
  7. "IET launches Amendment to Wiring Regulations". www.theiet.org. The IET . Retrieved 1 March 2018.
  8. Whitton, Nicole (2016). "BS 7671: the 18th Edition report". electrical.theiet.org. IET Electrical . Retrieved 8 February 2018.