Lighting Terminology


The lighting field - like many others - uses a variety of technical terms and jargon. Below, we identify and define many of the common terms. For information about our products, please get in touch - For advice on practical installation, we recommend choosing an NICEIC contractor who works to BS 7671.



A specification/size of bayonet mount for light bulbs and lamp holders. The diameter of a B15 cap is 15mm. The size is also known as ‘small bayonet cap’ or SBC. It is the smallest of the two common bayonet sizes in the UK and often used for smaller light bulbs/light fittings. The range includes three B15 light bulbs (mini tube, frosted mini globe and clear mini globe) and a range of B15 lamp holders.



A specification/size of bayonet mount for light bulbs and lamp holders. The diameter of a B22 cap is 22mm. The size is also known as ‘standard bayonet cap’ or BC or B22d or Ba22d. It is the most common bayonet size in the UK and widely used for light bulbs, lamp holders and light fittings. Urban Cottage Industries has a range of B22 light bulbs and lamp holders.


back box

An enclosure for a wall mounted switch or socket commonly made of pressed steel or moulded plastic. Back boxes are used to mount and house the wiring for wall sockets and switches. They can be surface mounted (where the rear of the box is fixed to a wall or other surface) or flush mounted (where the box is recessed into the wall or surface and only the socket or switch face plate is visible). The back box range includes single and double surface mounted back boxes.



An early thermosetting plastic commonly used in electrics and lighting due to its insulating and heat resistant properties. Bakelite usually has the distinctive dark brown/almost black colour, but an off-white/ivory colour is not uncommon. The Urban Cottage Industries Bakelite range includes wall lights, ceiling lights, lamp holders and plugs. The distinctive colour and finish of Bakelite gives electrical fittings a traditional or vintage look.



An alloy of copper and zinc widely used for engineered components, including light fittings. The properties of brass make it a highly versatile material: it is resistant to heat and conducts electricity. It can be easily forged and pressed, while being durable enough for a range of common applications and resistant to corrosion. New brass has a bright gold-like colour which can be maintained by lacquering or polishing. Alternatively, it can be treated to darken the finish or plated in a range of materials including nickel for a bright silver finish and copper. The collection includes brass lamp holders and the Maria wall lights with both brass and silver nickel plate finishes.


BS EN 60598

'BS EN 60598 Luminaires - General Requirements and Tests’ is the British Standard for all types of wired electrical light fittings, It covers wall and ceiling lights; pendant lights; desk, table and floor lights etc. ‘BS EN’ indicates a harmonised UK/European standard. The standard runs to hundreds of pages and includes a huge number of requirements and tests on matters such as insulation, earthing, wiring, strain relief on cables, heat resistance, labelling etc. All the applicable tests must be passed for a luminaire to comply with BS EN 60598. Every luminaire in our range is tested and certified to BS EN 60598.


BS 7671

British Standard 7671 also known as ‘the IET Wiring Regulations 17th Edition’ or ‘the Wiring Regs’ sets out standards for electrical installations. The standard is updated periodically as technology changes. The current version was published in 2008 and most recently revised in 2015. The full current standard is ‘BS 7671:2008+A3:2015 Requirements for Electrical Installations’. Electricians and contractors should be able to work to BS 7671 and all NICEIC contractors are approved to work to BS 7671. Although the standard is not itself legally binding, it comes close to having the force of law because Part P of the Building Regulations 2010 ‘Electrical Safety - Dwellings’ is legally binding and it requires that ‘Electrical installations should be designed and installed in accordance with BS 7671’.


Building Regulations or Building Regs

The Building Regulations 2010 are a UK statutory instrument approved by Parliament which impose a wide range of requirements in relation to the carrying out of ‘building work’. Part P of Schedule 1 to the Building Regulations imposes requirements in relation to electrical safety in dwellings. A crucial requirement is that electrical installations should be designed and installed in accordance with BS 7671. Significant electrical work (for example installing a new circuit, or a new consumer unit, or adding or altering a circuit in a bathroom) must be notified to and approved by a building control body (usually the local council). However, if the work is ‘self-certified’ by a registered competent person - which includes an NICEIC approved contractor - there is no need to notify the council or have them approve the work.


bulkhead light

A bulkhead light commonly refers to the type or style of light fitted to a bulkhead which is a structural wall in a ship or other vessel. Bulkhead lights are commonly ingress protected or IP rated and constructed so as to resist physical impact. The range includes a bulkhead light and an industrial lantern in a similar style.



A wire or bundle of wires that conducts electricity. Cable consists of a number of conducting cores, usually made from copper, which are insulated by plastic or rubber. Each core can be stranded (made from a number of wires) or solid (a single wire). For lighting applications, cable usually has two cores (live and neutral) or three cores (live, neutral and earth) depending on whether the light fitting needs to be earthed - Class I or Class II. Cable is also known as flex, wire or cord. It is important that the correct cable is used for a light fitting or appliance both in terms of the number of cores it has and the current it can carry. The range includes three core round cable, three core twisted cable, two core twisted cable and three core power cable in a huge range of colours and finishes. The product listing of each cable gives example uses and provides technical information on rated current, operating temperatures etc.


cable clamp

A fitting used for strain relief or to prevent cable being pulled out of an electrical fitting. Cable clamps usually have a movable plate or plates which are loosened and closed by means of two screws or bolts. Cable clamps are common in plugs and sometimes used for ceiling roses.


cable gland

A fitting used for strain relief - to prevent cable being pulled out of a fitting - and also to prevent the ingress of water or objects. Cable glands are generally made of two threaded pieces which when screwed together narrow the internal channel or compress a gland around the cable. The range includes an IP rated cable gland fitting.


ceiling light

A light fitting or luminaire designed to be fixed to the ceiling. Urban Cottage Industries uses the term to include both pendant lights which hang from the ceiling and lights which are fixed to the ceiling.


ceiling rose

In lighting terms, a surface mounted enclosure which is fixed to the ceiling to accomodate the wiring which connects a pendant light to the supply. Roses also function as decorative coverings for the unsightly holes in the plaster or other surface finish where the cable from the lighting circuit enters. Urban Cottage Industries ceiling roses are available in a range of styles, colours and finishes.



A hard material made by firing clay. Ceramic and porcelain were extensively used for lighting and electrical components because of their resistance to heat and insulating properties. Their use has become less common since the development of modern thermosetting plastics. The Urban Cottage Industries range includes ceramic lamp holders and ceramic wall lights. The use of ceramic often gives light fittings an industrial aesthetic.


CFL light bulb

A compact fluorescent light bulb uses the same technology as a fluorescent strip light, but is in the form/shape of a traditional incandescent light bulb. An electric current passes through a gas in the tube causing the emission of photons which make the coating on the inside of the tube glow. The Eco-Filaments (large globe shape or classic pear shape) use high-performance narrow-diameter CFL technology to create a decorative and effective light source.


circuit breaker

A mechanical device which is used to switch off the electricity supply to a circuit. A circuit breaker may operate automatically if it detects electricity flowing through the wrong path - such as through a person or earth conductor. An RCD is a form of circuit breaker.


Class I fitting

A light fitting which must be earthed in accordance with the manufacturer’s instructions in order to protect from electrical shock. In addition providing basic insulation of live parts, any accessible conductive parts - usually those made out of metal - which may become live in the event of a fault must be connected to earth. The connection to earth reduces the risk of electric shock and, if an RCD is installed, electricity flowing to earth should trip the RCD and cut off power to the device. Class I fittings are commonly referred to as being ‘single insulated’. The supply cable to Class I fittings must include an earth core to ensure they are connected to earth.


Class II fitting

A light fitting where, unlike with Class I fittings, protection against electric shock does not rely on basic insulation only. The fitting will have extra safety precautions such as having double layers of insulation or reinforced insulation. Check the instructions, but generally the supply cables to Class II fittings do not require an earth core. Class II fittings are commonly referred to as being ‘double insulated’.



Rigid or flexible tube or pipe used for protecting electrical wires or cables. Conduit tube can be made from various materials including plastic, aluminium and steel. More generally, 'conduit' is used to refer to the many interchangeable components which can be used for a conduit installation. Urban Cottage Industries has an extensive range of galvanised steel conduit products.


consumer unit

A component of an electrical installation which is used to distribute electricity from the main supply into subsidiary lighting and power circuits. The modern version of a fuse box. Consumer units have RCD protected circuits designed to minimise the risk of electric shock. The installation of a consumer unit or a new circuit from a consumer unit is covered by Building Regulations and must be completed in accordance with BS 7671



A style of lamp shade patented by the Benjamin Electric Company of Tottenham, North London in 1933. The openings in the neck of the shade allow heat to escape from around the lamp holder and wiring. All the Urban Cottage Industries Coolicons are made in the UK, faithful to the original Benjamin Electric design, and come in a range of genuine vitreous enamel and metallic finishes.



A shiny reddish-orange coloured metal commonly used for cable because it is ductile and an excellent conductor of electricity. In addition to its functional uses, copper is widely used decoratively. Bright copper is attractive and it can be distressed or allowed to weather naturally to produce verdigris.


cord grip

A fitting used for strain relief or to prevent cable being pulled out of an electrical fitting. Cord grips have various methods of operation. All the cord grips - for example on the ceiling roses and lamp holders - operate by a side locking grub screw which is both simple and effective.


double insulated

See Class II fitting.



A specification/size of screw mount for light bulbs and lamp holders. The diameter of an E14 cap is 14mm. The size is also known as ‘small Edison screw’ or SES. It is the smallest of the two screw mount sizes common in the UK and widely used for smaller light bulbs/light fittings. Urban Cottage Industries has three E14 light bulbs (mini tube, frosted mini globe and clear mini globe) and E14 lamp holders.



A specification/size of screw mount for light bulbs and lamp holders. The diameter of an E27 cap is 27mm. The size is also known as ‘standard Edison screw’ or ES. It is the most common screw mount size in the UK and widely used for light bulbs, lamp holders and light fittings. Urban Cottage Industries has a range of E27 light bulbs and lamp holders, and wall and ceiling lights which use the E27 specification.



A term that can be used in several ways. As a verb ('to earth something'), the act of connecting a light fitting or electrical appliance to earth. As a noun ('the light is connected to earth'), the terminal or wiring which ultimately leads to earth. All the uses are based on the concept that the earth or earthing creates a safe route with nominal resistance for current to flow through in the event of a fault. Current flowing to earth should cause an RCD to operate and disconnect the power supply.


Eco-Filament light bulb

A form of CFL light bulb which uses high-performance narrow-diameter fluorescent tubes. The technology was developed for back-lighting aerospace and medical screens and is extremely reliable and robust. Eco-Filament lights bulbs are available in large globe shapes or classic pear shapes.



In lighting terms, a length of cable on which are fixed lamp holders and light bulbs. Commonly used for temporary outdoor light for festivals and other events. Urban Cottage Industries festoon was withdrawn in 2015 because it no longer complied with the updated BS EN 60598 and we're committed to 100% product compliance.



A device for safeguarding electric circuits or appliances. When the current exceeds the rated value of the fuse - indicative of a fault such as current leaking to earth - the fuse wire melts and breaks the circuit. Fuses are still used in plugs. Modern consumer units are protected by RCDs rather then the wire fuses found in old fuse boxes.



A fitting which is attached to the top of a lamp shade which allows it to be hung using chain or the supply cord. Where the shade is spun from metal, it's not possible to spin an integral fitting for hanging the shade, so a gallery is used for this purpose. An alternative to a gallery is a shade carrier or where the neck of the shade fits onto the barrel of the lamp holder, as with the Coolicon lamp shades. Several of the other lamp shades have galleries made from galvanised steel.



Galvanised products have a protective zinc coating, usually to prevent corrosion. There are various processes which can be used to galvanise objects, each of which has a characteristic finish. Urban Cottage Industries uses zinc electroplating which creates the familiar bright zinc crystalline finish. And centrifuge or spin galvanising which produces the less common textured matt finish.



A flexible and compressible ring which is sandwiched between components to provide a seal or to prevent movement of the other components. Various Urban Cottage Industries products have gaskets, including the conduit boxes (to protect the face plates and ensure a close seal) and the IP rated ceramic bathroom and outdoor light (to prevent the ingress of water).


incandescent light bulb

A light bulb which has a wire filament - commonly tungsten - through which an electric current is passed. The current heats the filament causing the emission of light. The filament is protected by a glass bulb which is evacuated to form a vacuum or filled with an inert gas. We have a collection of incandescent light bulbs with a range of bulb shapes and filament styles. The bulbs have been SWISS-made since 1906



The Institution of Engineering and Technology publishes the IET Wiring Regulations or BS 7671 which set the standard for electrical installations. All electricians and contractors should be able to work to current IET Regulations which are the 17th Edition, published in 2008 and most recently revised in 2015.


IP rated

IP means ingress protected and light fittings may have an IP Code to indicate what level of protection is offered. The code is in the form IPXX where the first X is a digit which refers to protection against solid objects and the second X refers to the protection against water. IP22, for example, offers protection against fingers or similarly sized objects and dripping water. IP rating is governed by the international standard IEC 60529. The full IP codes are here together with more information about bathroom lighting.


lamp holder

A fitting into which a light bulb is inserted in order to connect it to the electricity supply. Also known as a light bulb holder or socket. The two main type are screw and bayonet and, both available in a range of sizes. Our range includes lamp holders in a range of styles, material and finishes. The four main lamp holder fittings are B22, B15, E27 and E14.


lamp shade

A fitting which is used in conjunction with a light source to direct or diffuse light. Sometimes written as a single word 'lampshade', and 'light shade' as an alternative. Lamp shades come in a huge range of styles and materials from simple paper shades to extremely complex designs.



Light-emitting diode - a semiconductor or solid-state light source which produces light through electroluminescence - or the release of photons of light by electrons. The development of white LEDs and their increasing efficiency in terms of lifespan and lumens per watt mean that LEDs are going to become the dominant light source in the future.


LED light bulb

A light bulb in the form/shape of a traditional incandescent light bulb but where the light is created by LEDs. The Eco-LEDs (dimmable or double-click dimmable) use high-performance LED technology.


LED-Filament light bulb

Also known as Filament-LED bulbs are light bulbs where the LEDs are positioned and shaped to mimic the filaments of incandescent light bulbs. See the range of high-performance LED filament bulbs here.


light source

Any source of light, including natural ones such as the sun and historic ones such as candles. Electric light sources commonly adopt a form - such as a light bulb - and a technology for creating the light such as incandescence (incandescent light bulb), fluorescence (CFL light bulb) or electroluminescence (LED light bulb).


light bulb

An electric light fitting which is plugged into a lamp holder and which emits light when a current is passed through it. Called light bulbs because they are most commonly bulb shaped, but the term also covers a range of other shapes. Light bulbs were originally incandescent, but there are now compact fluorescent and LED options. Technically, the word 'lamp' is used rather than 'light bulb', though for non-technical using 'lamp' can lead to confusion with 'luminaire' - see the next definition.



The technical umbrella term for a complete light fitting. The term encompasses wall, ceiling, pendant, floor, desk and table lights. The British and European standard BS EN 60598 sets out general requirements and tests which different types of luminaires should meet. All luminaires are tested and certified to BS EN 60598. The technical definition of luminaire in BS EN 60598 is 'apparatus which distributes, filters or transforms the light transmitted from one or more lamps and which includes all the parts necessary for supporting, fixing and protecting the lamps, but not the lamps themselves, and where necessary, circuit auxiliaries together with the means for connecting them to the supply.'


multi outlet or multiple outlet

A ceiling rose which has more than one cable outlet. The range includes multiple outlet ceiling roses in a range of metallic finishes and powder coated colours.



The National Inspection Council for Electrical Installation Contracting is a UK voluntary regulatory body for the electrical contracting industry. It was established in 1956. NICEIC approved electricians and contractors are assessed on a regular basis to ensure they are competent and working in accordance with BS 7671 or IET Wiring Regulations. NICEIC approved contractors can self-certify work under Building Regulations. All NICEIC contractors also carry public liability insurance in case anything does go wrong.



A silvery-white lustrous metal commonly used for plating brass components to give them an attractive and durable silver coloured finish. The Urban Cottage Industries range includes many nickel plated products including lamp holders, ceiling roses and and Maria wall lights.



An enclosure or box for wiring in the space behind an electrical or light fitting. The pattress may have a cover or a light fitting attached directly to it. Urban Cottage Industries has pattresses in a range of metallic or galvanised and black finishes. See also back box.


pendant light

An extremely common form of luminaire used for general or ambient light in a range of domestic, commercial and industrial settings. Pendant lights usually comprise a ceiling rose, a length of cable, a lamp holder and a lamp shade. Pendant lights can be designed using the Custom Lighting - pendant light configurator. When you have completed your design, it is built and tested to BS EN 60598



An electrical fitting with pins attached to cable. When inserted into a socket the pins conduct electricity into the cable and then on to the light fitting or electrical appliance.



The RAL system is a European colour matching scheme. It is designed to enable the accurate specification of colours for paint and other coatings and widely used in architecture, construction and industry. Specifiers and manufacturers have identical RAL reference samples or panels and can specify the colour of coating by reference to the RAL number rather than the actual exchange of samples. The scheme takes its name from the German Reichs-Ausschuß für Lieferbedingungen und Gütesicherung (State Commission for Delivery Terms and Quality Assurance). Urban Cottage Industries colour finishes - vitreous enamel and powder coating - are specified using the RAL system. More information about RAL colours is here.



Another name for a lamp shade where the main purpose of the shade is to reflect light in a direction. All of our enamel lamp shades are 'reflectors' in that they reflect light in a certain direction - downwards when used as pendant shades. The reflector is a common form of functional shade because it maximises the amount of light cast in one particular direction rather illuminating other areas directly.



A residual current device or RCD is designed to prevent death or serious injury from electrocution. It offers greater protection than fuses and ordinary circuit breakers because if it detects electricity flowing through the wrong path - such as through a person or earth conductor - it switches off the supply instantaneously. RCDs can be installed in a consumer unit, as an integral part of a socket or switch, or as plug in devices to protect appliances. BS 7671 also called the IET Wiring Regulations has required all new or re-wired circuits in homes to include RCD protection.



Originally, a sconce was a bracket fixed to a wall with a level plate on which a candle could be placed. Since the advent of electric lighting, sconce is commonly used to refer to a simple wall light in a similar form as the original sconces. The wall light range includes the Maria Sconce.


shade carrier

A fitting for the inside of a lamp shade which allows it to be mounted on a lamp holder. Shade carriers are also called harps. Carriers or harps have a ring which fits round the barrel of the lamp holder. The rings come a range of sizes and there can be issues finding the right size ring. 40mm is a fairly standard size for new lamp shades and reducer rings are available where the shade ring is too big for the lamp holder. Where the lamp holder can be used to support a light shade, each lamp holder listing gives the size of the barrel.


shade guard

A guard or cage made of wire which is attached to a lamp shade to protect the light bulb or other light source from physical impacts. The use of shade guards was common in factories and mills. The industrial lamp shades can be fitted with a specially designed shade guard.


shade ring

A threaded ring which is screwed onto the barrel of a lamp holder to secure the shade carrier of a lamp shade (or the neck of the lamp shade itself) in place. Depending on the design of the lamp holder and how it is oriented, more than one shade ring may be required.


simple light

A luminaire comprising of a lamp holder, a length of cable, a plug and some means of securing the cable. Simple lights can be designed using the Custom Lighting simple light configurator. When you have completed your design, it is built and tested to BS EN 60598


single insulated

See Class I



Originally a genre of literature which incorporated or referenced technological and design elements of 19th-century industrial steam-powered machinery. The term is now used more broadly to describe objects which incorporate or allude to the the design of Victorian machinery. See the Maria Steampunks.



A point at which an electrical or light fitting is connected to the electrical supply. Terminals come in a huge variety of designs. Perhaps the most common is the familiar brass terminal with a hole for the wire which is then secured by means of a screw.


WAGO connector

WAGO Kontakttechnik GmbH & Co is a German company which manufacturers wiring devices - things for joining wires together. In contrast to traditional screw operated terminal bock, WAGO connectors are much safer and simpler to use. All wired wall and ceiling lights are provided with WAGO connectors for ease of installation.


wall light

A light fitting or luminaire designed to be fixed to the wall. The range includes wall lights in a range of styles, designs, colours and finishes.



A green or bluish patina formed on copper or copper alloys. The most usual form is copper carbonate. Verdigris is commonly seen on copper sheeting when used on roofs or on bronze statues. Verdigris is a beautiful and highly desirable decorative finish and two of our lamp shades - the 360mm industrial and the 190mm kitchen - are available with verdigris finishes.


vitreous enamel

A coating made from glass which is applied as a powder or suspension and then baked at high temperature. Unlike other surface finishes such as paint, vitreous enamel is extremely hard wearing and resistant to discolouring or fading. It is available in a range of colours. The Urban Cottage Industries range of lamp shades are available in a range of vitreous enamel colours.


Free shipping

on UK orders over £60

Customer service

Chat, WhatsApp, Email or Phone

Refer a friend

Share our promo code & earn discounts

Secure payments

Card, Apple Pay or .pdf quotes & invoices