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There are three main types of lighting available:
- Incandescent lighting is most commonly seen as traditional tungsten light bulbs in small spaces and homes. These lights rely on the resistance of the filament to electricity, causing it to heat up.
| Advantages |
Disadvantages |
| Low purchase price |
Low efficacy - only 8 to 15 lumens/watt |
| Excellent colour rendering |
Short life, usually 1000 hours |
| Immediate full light when switched on |
Needs regular attention |
| Ease of dimming |
High running cost |
| Sparkle lighting effects can be created |
High heat output (94% of energy is heat, 6% is light) |
| Operates in any plane (universal operating position) |
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- Discharge lighting is the most common lighting found in commerce and industry and includes Fluorescent, Sodium, Mercury and Metal Halide lighting. These are all more efficient than incandescent lamps but they do need special “control gear” to operate.
Fluorescent lighting is often the best choice for lights that are mounted below 5m. Above this height smaller numbers of higher Wattage Sodium, Mercury or Metal Halide lights are used. This is partly because access at these heights is difficult, and because light needs to be able to carry greater distances to the working space.
- Light Emitting Diodes (LED) rely on the movement of electrons from an electric current. They produce little waste heat and now come in many different bulb types. The technology is still in development but is now becoming increasingly used in street lighting
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