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Incandescent or Fluorescent

One of the first decisions when shopping for fixtures is what type of bulb to choose. In the lighting industry, bulbs are called lamps. Incandescent bulbs, the standard lamps for over a century, now come in several new varieties, including halogen and xenon. Standard incandescent. Incandescent bulbs have several advantages:

• They are inexpensive and widely available.

• They are easily dimmed.

• They are available in a wide range of wattages.

They also have several disadvantages:

• The lamp life is relatively short (about 750 hours).

• The light yellows as the lamp is dimmed.

• They are the least energy efficient of available lamps. Halogen. The halogen (or quartz) lamp is an improved version of the incandescent lamp. Halogen lamps contain halogen gas, which allows the bulb to burn brighter and last longer.

Advantages of halogen lamps:

• They are usually smaller than standard incandescents.

• They last longer than standard incandescents (2,500 to 3,000 hours).

• They are more energy efficient than standard incandescents.

• They lend themselves well to being focused in a narrow beam.

Disadvantages of halogen lamps:

• The light yellows as the lamp is dimmed.

• Dimming may shorten the lamp life.

• The glass envelope of the lamp should not be touched without gloves on.

• Halogens can get very hot, and some types of halogen fixtures have been associated with fires.

Many halogen fixtures operate at 12 volts DC and require a transformer (see "Low-Voltage Lighting," 5/96). Xenon. Xenon lamps are similar to halogen lamps, with several advantages:

• They don't get as hot as halogen lamps.

• The lamp life is much longer than that of halogen lamps (about 20,000 hours).

• There is no need to avoid handling xenon lamps with your fingers. Fluorescent. In recent years, residential use of fluorescent lamps has greatly increased, due to improvements in fluorescent ballast technology and greater variety in the available color rendition of fluorescent lamps. Moreover, some states, including California, have mandated the inclusion of energy-efficient fluorescent fixtures in kitchens and bathrooms. Fluorescent lamps require a ballast; most compact fluorescents include the ballast with the lamp. Solid-state or electronic ballasts are less likely to hum than heavy magnetic ballasts. The best types of electronic ballasts permit fluorescent lamps to be dimmed.

Advantages of fluorescent lamps:

• They last a long time (between 10,000 and 22,000 hours).

• They are very energy efficient (providing three to five times the light output per watt of a standard incandescent).

• They produce less heat than a standard incandescent or a halogen, so they can be installed closer to combustible materials in a closet.

• They do not change much in color when dimmed.

Disadvantages of fluorescent lamps:

• Some ballasts, especially cheap magnetic ballasts, have an irritating hum.

• As they age, they produce less light (halfway through their expected life, they may produce 20% less light than when new).

• They are usually large and are hard to focus for accent lighting.

• They can be hard to start in cold temperatures, although cold-weather ballasts are available to solve that problem.