Bright light of halogen

Although halogen lighting technology has been in general use in Europe for some years, it came to the United States home furnishings market only about a decade ago. Interest has intensified in the last three years, and today, anyone in the market for a lamp will find a wide variety of models especially designed for halogen bulbs. In case you're wondering what halogen is, Philip Wolf, vice-president of Nessen Lamps Inc., has a simple explanation.

``A halogen bulb is an advanced and improved incandescent bulb,'' he says. ``It gets its brightness from an electrically charged tungsten filament encased in a halogen gas-filled quartz [not glass] outer casing or bulb.''

What are the advantages of halogen? For one thing, halogen bulbs produce a warm, pleasing white light and the lamp life is three to four times greater than regular incandescent bulbs. And they can be effectively and easily dimmed, unlike fluourescent bulbs.

Also, their lumen output stays constant and uniform throughout their life. In a normal bulb, the light diminishes gradually as the tungsten filament burns and blackens the inside of the bulb. This doesn't happen in a halogen bulb, and there is no loss of luminosity. Energy savings result from the fact that for the same wattage, a halogen bulb yields twice as much brightness.

In addition to all that, the tiny halogen bulb is about one-tenth the size of a regular bulb, a fact that has opened up a whole new field of sleek, modern designs.

Halogen lamp design was first associated with the look of high-tech European modern, a look which remains strong. And many of the lamps being introduced today make pretty startling design statements. But halogen is now also being adapted to some traditional 18th- and 19th-century styles, and to low-voltage track lighting, as shown by Lightolier and other companies. Also, because halogen bulbs are more efficient and deliver more light output than regular incandescent bulbs, an interior designer can specify fewer fixtures for the same space.

Now widely available, halogen bulbs are being used for the very popular ``uplighting'' torchieres and wall sconces, as well as for recessed downlights, picture lights, desk lamps, and reading lamps. Prices vary; the ``Micro desk lamp,'' for example, is featured by both Conran's and the Museum of Modern Art Store for about $50. Other models can range as high as $1000.

``We still have to explain what halogen is,'' one lighting showroom manager remarked, ``but we find that people seem to like both the styling of the lamps and the amount of light they put out.''

One possible disadvantage to halogen lamps is the special handling that the bulbs require, because of the intense heat they generate.

``We use wire mesh screening to protect our halogen bulbs, as a normal safety precaution,'' says Howard Shattuck, vice-president of design for the Paul Hanson company. ``And we provide hang tags of hints and precautions with every lamp. The only problems we have encountered have resulted from the failure of customers to read and follow instructions and thus sometimes render the bulbs non-functional.''

Sharon Dalton of Underwriters Laboratories Inc., an independent testing laboratory that checks out equipment for electric shocks and fire and casualty hazards, explains that the lab tests halogen lamps ``as we do any portable electric lamp, but with additional requirements. We see that a halogen lamp has guards to protect people from coming in contact with the bulb. We feel that a guard, or a shield, or a diffuser is very important.

``We also make several performance tests, under severe conditions, to make sure that the bulb could not come into contact with, and ignite, such combustible materials as carpets, drapery, and upholstery fabrics.''

Ms. Dalton points out that application to an underwriters laboratory is strictly voluntary on the part of manufacturers and is not required by any federal or state government agency, nor is there a law that requires an approved listing mark. ``Companies come to us voluntarily for testing and approval of products, and listing does generally improve marketability.''

Some lamp companies have sought such Underwriters Laboratories Inc. (UL) listing, Dalton says. Many have not. Some are in process of application. All halogen lamp manufacturers, she explains, furnish printed instructions and precautions, and it is very important that people read these before they attempt to use the lamps.

She also warns that halogen lamps should be placed in areas where they cannot be easily knocked over by small children, and a fair distance away from any combustible fabrics or carpets.

When changing a halogen bulb, she urges, take special care to wait for the bulb to cool and use gloves or a cloth when handling the bulb. Since oil from fingers will destroy the bulb, any finger marks should be wiped off with alcohol before reconnecting the lamp.