Acronyms & Abbreviations

The candela; (cd) is the unit of luminous intensity in the International System of Units (SI), that is luminous power per unit solid angle emitted by a point light source in a particular direction. Luminous intensity is analogous to radiant intensity, but instead of simply adding up the contributions of every wavelength of light in the source's spectrum, the contribution of each wavelength is weighted by the standard luminosity function (a model of the sensitivity of the human eye to different wavelengths). A common wax candle emits light with a luminous intensity of roughly one candela. If emission in some directions is blocked by an opaque barrier, the emission would still be approximately one candela in the directions that are not obscured. The word candela is Latin and Italian for candle.

The SI base units are the standard units of measurement defined by the International System of Units (SI) for the seven base quantities of what is now known as the International System of Quantities: they are notably a basic set from which all other SI units can be derived. The lighting related units and their physical quantities are the ampere for electric current, the kelvin for thermodynamic temperature, and the candela for luminous intensity. The SI base units are a fundamental part of modern metrology, and thus part of the foundation of modern science and technology. The names and symbols of SI base units are written in lowercase, except the symbols of those named after a person, which are written with an initial capital letter. For example, the metre has the symbol m, but the kelvin has symbol K, because it is named after Lord Kelvin and the ampere with symbol A is named after André-Marie Ampère. [Read more...]

The Volt (symbol: V) is the unit of electric potential, electric potential difference (voltage), and electromotive force in the International System of Units (SI). It is named after the Italian physicist Alessandro Volta (1745–1827). One volt is defined as the electric potential between two points of a conducting wire when an electric current of one ampere dissipates one watt of power between those points. Equivalently, it is the potential difference between two points that will impart one joule of energy per coulomb of charge that passes through it.

The Watt (W) is a unit of power. It is defined by the internal system of units as a unit derived from 1 kg⋅m2⋅s−3 (1 joule per second). To describe watts in different multiples, the words below are used. Microwatt - (µW) - 1 millionth of a W (10-6 W) Milliwatt (mW) - 0.001W Centiwatt (cW) - 0.01W Deciwatt (dW) - 0.1W Watt - (W) - 1W Decawatt (daW) - 10W Hectowatt (hW) - 100W Kilowatt (kW) - 1000W Megawatt (MW) - 1 million W (106 W) To see more Watt multiples, view Orders of magnitude (power) (Wikipedia).

An LED is a diode which emits visible or infrared light when voltage is applied. These are common in all forms of lighting. LED is short for 'Light-Emitting Diode'. The creation of the first LED was reported by Russian inventor Oleg Losev who did so in 1927, but they were not made use of for several decades after the discovery. The voltage applied to and LED is regulated by LED drivers so that the the LED does not overheat and become damaged.

FSC stands for The Forest Stewardship Council it is an international non-profit, multi-stakeholder organization established in 1993 that promotes environmentally sound, socially beneficial and economically prosperous management of the world's forests. All wood with this certification is accredited and comes from a sustainable source.

The ampere (amp/A) is the SI base unit for electronic current and is equal to one coulomb per second (C/s). In other words, it is equal to 6.241509074×10¹⁸ electrons worth of charge moving past a point in a second. It is named after French mathematician and physicist André-Marie Ampère.

The Kelvin (K) is the SI base unit of temperature, named after the Belfast-born engineer and physicist William Thomson, 1st Baron Kelvin (1824–1907). Kelvin uses absolute zero as the null point (0°K) which is equivalent to -273°C (Celsius) or -459.67°F (Fahrenheit).

One Kilowatt hour (kWh) is equal to one thousand Watts sustained for an hour. Its SI base unit symbol is kWh. In terms of human power, a healthy adult male manual labourer performs work equal to about half a kilowatt-hour over an eight-hour day.

The Colour Rendering Index (CRI) measures how accurately a lamp reproduces the colours of the object it illuminates. The colours picked up by our eyes may differ from colours under natural lighting when using a low CRI lamp, and CRIs measure how accurate the lighting is to natural lighting so that we don't see any changes in colour. The value given by a CRI is an easily quantifiable score from 1-100, 100 being the best score and 1 being the worst.

The IP (Ingress Protection) rating presents the level of protection a light fixture has against dirt and water. Any fixture that is used in a bathroom, wet environment or outdoors should have an IP rating that is high enough to stop dirt or water entering the fixture, as to protect it from being damaged. An IP rating consists of two digits. The first digit represents protection against the ingress of solid objects, and the second digit represents protection against the ingress of liquids. The higher the value of either digit, the greater the protection. Please see this Blog for more details about IP in Bathrooms.