Buying Guide for Domestic Electrical Appliances

Buying Guide for Lighting

1. Common Size / Rating
   • Incandescent lamp bulb: from 5W to 250W
     Common ratings are 25W, 40W, 60W and 100W.
   • Compact fluorescent lamp: from 4W to 30W
   • Fluorescent tube: from 14W to 65W
     Common lengths are 600mm, 1,200mm and 1,500mm.
2. Selection of Lighting
   • Incandescent lamp
     • It converts only 10% of the energy into light while 90% of the energy is converted into heat.
     • Efficacy is about 24 lumens per watt.
     • There are two types of socket base, the Bayonnet type and Edison-Screw type.
     • The expected working life is about 750 to 2,500 hours.
     • Halogen lamp (also named as tungsten halogen or quartz lamp) is a subset of this group. It gives whiter light and better light quality. Efficacy is about 36 lumens per watt. Its expected working life is about 1,000 to 3,000 hours. Some halogen lamps operate at 12-volt or 24-volt supply and therefore step-down transformers are required.
   • Compact fluorescent lamp
     • It gives better light quality, from warm white light colour (similar to incandescent lighting) to natural daylight.
     • Compact fluorescent lamps can replace incandescent light bulbs easily.
     • Efficacy is about 50 to 83 lumens per watt.
     • The expected working life can reach 10,000 hours.
     • "Recognition Type" Energy Efficiency Labelling Scheme has been launched for compact fluorescent lamps. Try to choose a compact fluorescent lamp with an energy label to save energy.
   • Fluorescent tube
     Different types of fluorescent tubes are summarized as follows:

     Lamp Type	Fluorescent Tubes
     	T12	T8	T5	T5(HO)
     Diameter in mm (inch)	38 (1.5)	26 (1)	16 (5/8)	16 (5/8)
     Type of ballast	Electro-magnetic	Electro-magnetic or electronic	electronic	electronic
     Approximate Efficacy (lumens per Watt)	64	92	104	94
     Expected Working Life (hours)	20,000	20,000	20,000	20,000

     T8 fluorescent tube may be used as a direct replacement for T12 tube. However, the length and socket design of T5 lighting are different from those of T8 and T12 so additional installation works/accessories are usually required if a T5 tube is to replace a T8 or T12 tube.
   • Compact fluorescent lamps and fluorescent tubes contain a little amount of mercury and you should handle and dispose them carefully and safely.
   • Not all compact fluorescent lamps and fluorescent tubes are dimmable. Incorrect dimming can shorten their life, damage the lighting or even cause fire.
   • For other energy efficient tips and safety precautions, please refer to our website "Efficient Use of Electricity|Efficient Use of Electricity" and "Safety Tips on Using Electricity|Safety Tips on Using Electricity" respectively.