It is important to use the right ballast to ensure the luminaire also ignites at low temperatures.

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1 LINGO n. pl. ling goh. (Informal) The specialized vocabulary of a particular field or discipline. The language and speech, esp. the jargon, slang, or argot, of a particular field, group, or individual: Once you catch onto the lingo, everything becomes clear.

2 BALLASTS A device also known as control gear, intended to limit the amount of current in an electrical circuit. It obtains voltage, current and waveform from a power source in order to operate electric-discharge lamps such as fluorescent and high intensity discharge (HID) lamps. It is important to use the right ballast to ensure the luminaire also ignites at low temperatures. An environmentally friendly choice of ballast is a HF-ballast (High frequency) HF-BALLAST: Research studies have indicated that people in workplaces where luminaires equipped with HF-ballasts are used feel better, are less tired and achieve more. The HF-ballast offers more energy efficiency, i.e. the installed luminaire output and performance losses are lower, and there is also less heat. Because of this cooling and air-conditioning systems can be reduced and therefore cover an overall saving in energy costs. Maintenance and service costs are also lower due to the improved life of the light sources. ELECTRONIC MAGNETIC BALLAST 60 Hz 60 Hz

3 BALLAST FACTOR The Ballast factor (BF) is the measured ability of a particular ballast to produce light from the lamp it powers. The ballast factor comes from dividing the lumen output of a particular lamp-ballast combination by the lumen output of the lamp source. This factor, which usually results in a number less than one, accounts for the fact that some lumen loss results when operating lamps off a ballast. The ballast also needs wattage to operate for the lamp source, hence why total watts in a 28 W luminaire would sometimes be 31 W. The ballast uses 3 watts of the total lamp wattage. Any single ballast may have several different ballast factors, depending on the number and types of lamp/s it s operates. RATED LUMENS: BALLAST FACTOR: ACTUAL LUMENS: 3000 X 0.79 = 2370

4 CANDELA The intensity of a light source in a specific direction is expressed in candelas (cd). Any light source will have many different intensities, depending on the sources direction of distribution. 800 CANDELAS 50 CANDELAS 3100 CANDELAS

5 CANDLEPOWER DISTRIBUTION This is defined through a polar curve representing the luminous intensity of a lamp or luminaire in a plane which is normally shown in a numerical table or a graph. The distribution of light is usually based around a vertical axis of 0 degrees up to 60 degrees, which is known as the nominal cut-off angle for luminaires to avoid discomfort glare. Looking at the candlepower/polar distribution on a graph, you can identify a range of intensities your choice of lamp/luminaire will provide. Below are some examples.

6 COLOUR TEMPERATURE The colour temperature measured in degrees Kelvin (K) indicates the light source s colour appearance and varies in a range of K K is considered to be neutral white. Temperatures lower than 3500 K is considered as warm, and temperatures higher than 4000 K are considered cool. Colour temperature and colour appearance of fluorescent lamps is controlled by the combinations of fluorescent materials used to coat the inside of the tubes. This makes it possible to produce different tones of white light. WARM 2700K COOL WARM INTERMEDIATE COOL SOURCE Tungsten Halogen Cool White Linear Fluorescent High Pressure Sodium Warm Compact Fluorescent CCT 3000 K 4200 K 1900 K 2700 K

7 COLOUR RENDERING The ability of a light source to reveal the true colours of an object is called Colour rendering. The CRI (Colour Rendering Index) for indoor lighting should be above 80 and for good colour rendering above 90. The value for maximum colour rendering is defined as 100. CRI = 90 CRI = 70 CRI = 50 CRI / RA FIGURES (COLOUR RENDERING INDEX) FOR LUMINAIRES: Incandescent 100 Tungsten Halogen 100 Standard Fluorescent (Halophosphor) 60+ Fluorescent (triphosphor) 80+ Specialised Fluorescent (enhanced CRI) 90+ Standard Metal Halide 65 Ceramic Metal Halide 80+ Standard Mercury Vapour 45 High Pressure Sodium 25 White High Pressure Sodium 60 Low Pressure Sodium 15 Light Emitting Diodes (LED) 70+

8 COLOUR APPEARANCE The colour of an object or a light source gives it the colour appearance. There can be white light, blue light, red light, etc, but ultimately there are no right or wrongs when choosing a particular colour appearance. Your decision is more likely going to be based on the interior design, fittings, personal taste and cultural influences. LUMINOUS EFFICACY (LM/W) The light source s luminous efficacy is the relation between its luminous flux and the electrical power used. The higher the lumens per watt in a light source, the more efficient it is. Keep in mind that the luminous efficacy applies to the light source only. The ballast losses have not been taken into consideration. 100W INCANDESCENT LAMP 1750 LUMENS EFFICACY RESULTS 18 LUMENS WATT 32W 12 CIRCULAR FLUORESCENT LAMP 1800 LUMENS + BALLAST BALLAST FACTOR = LUMENS WATT 70W METAL HALIDE LAMP 5200 LUMENS + BALLAST BALLAST FACTOR = LUMENS WATT

9 LAMP TYPE Tungsten Filament 5-20 Tungsten Halogen High Pressure Mercury Vapour Metal Halide Tubular Fluorescent inc. Compact Fluorescent High Pressure Sodium Low Pressure Sodium Vapour Light Emitting Diode (LED) EFFICIENCY LUMINOUS EFFICACY lm/w (white) The ratio of the luminous flux (lumens) emitted by a luminaire to that emitted by the lamp/s used. Luminous efficiency expresses the percentage of the initial lamp lumens that are ultimately emitted by the luminaire. The efficiency of a luminaire does not necessarily indicate its effectiveness in delivering lumens to the workplane, or whether it s even appropriate for the application its installed for. Depending on the application, the less efficient luminaire may infact be the appropriate choice because of reduced glare potential. 100% EFFICIENCY 70% EFFICIENCY

10 GLARE A term used where effects are produced due to the luminance of a visual system and the visual field being significantly different to which the eyes are adapted, which can cause annoyance, discomfort, or loss in visual performance and visibility. Direct glare is caused by bright areas, such as luminaires, ceilings and windows that are in line of sight. Indirect glare is caused by light reflecting off a surface, an example of this is obstruction glare, which is a building outside a window reflecting daylight in line of sight, causing visual discomfort. Two major types of glare are: 1. Disability Glare: Visual impairment where eyesight is temporarily or permanently effected. 2. Discomfort Glare: Where your peripheral vision captures a source of contrast or glare in the surrounding environment. (For further information please refer to the LUX booklet) DIRECT GLARE FROM WINDOWS AND LUMINAIRES REFLECTED GLARE ON COMPUTER SCREEN FROM CEILING LUMINAIRES

11 ILLUMINANCE The illuminance determines the density of the luminous flux at a point on a particular surface, which is measured in lux (lx) which equals lm/m2. Lux levels are derived from the Australian Standards, which demonstrate recommendations of lux levels for particular environments to accommodate visual performance. (For further information please refer to the LUX booklet) 1600 LUX 1200 LUX 300 LUX 500 LUX

12 LAMP A generic term for a source created to produce optical radiation. In simple terms, it is designed to produce light from electricity. Below are examples of several lamps on the market today: Fluorescent Mercury Vapour Metal halide High pressure sodium (For further information please refer to the LAMPS booklet) FLUORESCENT INCANDESCENT HIGH INTENSITY DISCHARGE

13 LIFE AVERAGE RATED Average rated life (of a light source) is usually the number of hours when 50% of a large group of lamps have failed. For incandescent lamps, the number of hours per start does not significantly affect the average rated life of the lamp. However, for discharge lamps such as fluorescent and high intensity discharge (HID), fewer hours per start (more switching on/off) decrease lamp operating life, and more hours per start increase it. The actual life of a lamp is the value for life expectancy. Listed below are a few typical average rated life ratings for some common light sources: PERCENT SURVIVING LAMPS WHEN 50% OF THE TEST LAMPS HAVE FAILED, THE AVERAGE RATED LIFE HAS BEEN REACHED PERCENT OF AVERAGE LIFE LAMP TYPE LUMINOUS EFFICACY lm/w Tungsten Filament Tungsten Halogen High Pressure Mercury Vapour Metal Halide Tubular Fluorescent inc. Compact Fluorescent High Pressure Sodium Low Pressure Sodium Vapour Light Emitting Diode (LED) UP TO

14 LIGHT Radiant energy that is capable of exciting the retina in the eye producing a visual sensation. Light is a form of electromagnetic energy. Electric light sources convert electrical energy to visible radiant electromagnetic energy, which initiates the seeing process. Light must be reflected or transmitted by an object, received by the rods and cones of the eye, and then interpreted by the brain as a visual image. Rods are cells in the retina of the eye which function in darker conditions where there is less intense light. This is also in relation to Scotopic vision. Cones are the opposite, as they function where brighter light is visible. This relates to Photopic vision.

15 LUMEN Lumen is a unit of luminous flux. The lumen is the time rate flow of light, it can be considered as the measure of the overall light output of a lamp. Ratings are determined and published by lamp manufacturers. 675 LUMENS During the design process, lighting specifiers/designers use the lumen ratings of lamps to predict the final illuminance in a space. Since energy-efficiency design has become more important these days, designers also calculate the lumen output per watt consumed (efficacy) of the range of lamp choices. Below are some examples of lamps with their lumen ratings. LAMP WATTAGE LUMENS Fluorescent T Fluorescent T Fluorescent T Metal Halide MT Metal Halide MT

16 LUMINAIRE A complete lighting unit consisting a lamp or lamps and a ballast (when applicable) together with the parts designed to distribute the light, to position and protect the lamps, and to connect the lamps to the power supply. A luminaire, also known as lighting fixture, contains housing, lamp/s, socket/s and electrical wiring. In addition to these parts, a luminaire may also contain extra components such as a reflector, lens, diffuser, louvre, gasket, latch, decorative trim, or mounting hardware. These extras are used to provide protection, improve efficiency, appearance, control glare or affect the direction of distribution. BALLAST HOUSING REFLECTOR LAMP LENS/DIFFUSER TRIM BAFFLE MOUNTING FRAME REFLECTOR HOUSING LOUVRE MOUNTING FRAME LAMP BALLAST LENS/ DIFFUSER TRIM

17 LUMINANCE Luminance is the photometric quantity associated with one s perception of brightness. It s the amount of light that reaches the eye of the observer measured in units of luminous intensity (candelas) per unit area (m2). If a surface is visible it has luminance. REFLECTANCE Reflectance are the ceiling, walls, floor or other objects which have the potential to reflect or absorb light from a light source. A brighter surface will reflect more light into an area, whereas a darker surface will absorb more light and therefore reflecting minimal light into an area. Different textures of the above can provide varying reflectance values. Concrete, brick, plaster, timber all have different values given their different colours and textures. These factors can effect the illuminance values during the design process. Below is a diagram of commonly known textures for ceilings, walls and floors:

18 APPROXIMATE REFLECTANCES OF TYPICAL BUILDING FINISHES BUILDING SURFACE REFLECTANCE MATERIAL OR FINISH CEILINGS 0.8 White water-based paint on plain plasterboard 0.7 White water-based paint on acoustic tile 0.6 White water-based paint on no-fines concrete 0.5 White water based paint on wood-wool slab WALLS 0.8 White water-based paint on plain plasterboard; tiles: white glazed 0.4 White fibre cement; Brick: concrete, light grey: Portland cement, smooth 0.35 Stainless steel 0.3 Brick: common 0.25 Concrete, light grey; Portland cement, rough (as board marked); brick: red; Timber panelling: light oak, mahogany, gaboon 0.2 Timber panelling: teak, medium oak: brick: concrete, dark grey 0.15 Brick: dark hard-fired 0.05 Chalkboard, painted black (new) FLOORS & FURNITURE 0.8 Paper, white 0.45 Cement screed; PVC tiles: cream: carpet: light grey, middle buff 0.35 Timber: light 0.25 Timber: medium: PVC tiles: brown and cream marbled: carpet: turquoise, sage green 0.2 Timber: dark: Tiles: cork, polished 0.1 Quarry tiles: red, heather brown: Carpet: low maintenance : PVC tiles: dark brown: Timber: very dark

19 IP CLASSIFICATIONS Luminaires are given an IP classification. The IP classification consists of a two digit code that describes the degree of protection against solid objects as well as moisture of water. Standard luminaires will have an IP classification of IP 20 or higher. However, luminaires which are more likely to be exposed to dust or water/rain, will have an IP classification of IP 54 or higher. Below is a table describing all the IP classifications: Design according to first number Design according to the second number Unprotected Drip proof Rain proof Splash proof Jet proof Water-tight Submersible Unprotected IP 00 IP 01 Protected IP 10 IP 11 IP 13 Protected IP 20 IP 21 IP 23 Protected IP 40 IP 41 IP 43 IP 44 IP 45 Dust-proof IP 54 IP 55 Dust-proof IP 65 IP 67 IP 68