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Light Bright

There’s now an intelligent approach to lamp maintenance, disposal, and performance.

By Mary Claire Frazier

Disposal of fluorescent and HID lamps that contain mercury and lead can be a trial for facility managers. Almost every state’s regulations differ from the others. But they all require time consuming storage, packaging, paperwork, and organization.

Some customers wonder if it wouldn’t just be easier, more economical, and more environmentally friendly use incandescent lamps exclusively to simplify the process. Unfortunately, this isn’t an option.

Regulations have been evolving for several years to encourage recycling. Both California and New York now require recycling of all fluorescent and HID lamps, and other states won’t be far behind.

From top to bottom: T6 metal halide, PAR38 metail halide, T5 fluorescent, T8 fluorescent. Which lamps would you rather store and dispose of? Photo provided by Candela Architectural Lighting Consultants.

Many require recycling if a facility disposes more than a certain minimum number of lamps. As a result, quite an industry has sprung up to accommodate these requirements. Facilities can pre-order boxes in which to ship spent lamps to recycling plants and lamp crushers to reduce the volume of waste.

Incandescent lamps can be thrown in the trash and disposed of in any landfill. Sure, fluorescent and HID lamps are more efficient at producing light, but are they really worth all that mercury in landfills potentially leaching into groundwater? The answer is yes.

The Environmental Protection Agency (EPA) estimates that only 1% of the mercury released into the environment comes from mercury containing lamps, that in comparison to 87% due to incineration and coal fired power plants. Still, every kilowatt hour saved by the use of more efficient sources to generate light prevents 0.04 milligrams of mercury emissions from power plants. However, the EPA recommends that all fluorescent lamps be recycled as a way of reducing mercury in landfills, even though low dose lamps are now prevalent and many have so little mercury that they are legally exempt from recycling requirements.

Waste Reduction Options

There are several options for reducing the volume of lamp waste that also provide other savings for a facility. The quest for smaller sizes in fluorescent light fixtures has been progressing for several years and is a familiar scene in the marketplace. Lamps are getting smaller, and smaller lamps require less storage space.

T5 fluorescent lamps have several advantages over larger T8 lamps. They require less mercury to operate because of the lower volume of the cavity and contain less material that needs to be recycled. Because smaller lamps allow more precise reflectors to control the optics of a light fixture, fewer light fixtures are required to provide the same light levels.

An even more interesting development has been taking place in metal halide fixtures. With the development of ceramic metal halide lamps, this efficient technology has migrated inside over the last few years.

The early generations of ceramic metal halide lamps included mostly ellipsoidal and PAR style bulbs. Ellipsoidal lamps look like traditional metal halide lamps and require bulky fixtures because of the size of the lamp and the need to add a reflector around the omni-directional lamp.

PAR lamps, with thick glass lenses on integral reflectors that house the ceramic capsule, produce a single specific beam spread. These lamps can be used in fairly basic fixtures, since they carry their optics with them. The fixture must only provide a socket and ballast.

Newer generations of ceramic metal halide lamps include T style lamps that are either double-ended or single-ended tubes. These lamps require fixtures that incorporate optical systems to determine the distribution of the light produced by the fixture. This means a more sophisticated and expensive fixture is part of the first cost of a project, but substantially less cost is incurred over time due to the smaller storage capacity requirements and the elimination of the need to buy a reflector every time it is necessary to purchase a lamp.

In fact, many manufacturers are offering fixtures that have interchangeable optics for these lamps. This means a single housing type can be used to produce a variety of beam spreads to accommodate various lighting functions. The reflector systems can be changed in the field whenever the fixtures need maintenance, and facilities departments are only required to store one lamp type in order to maintain that fixture.

With sophisticated optics and good quality construction that addresses heat dissipation issues, these lamp/fixture systems can produce an amazing amount of light from very little energy. The crisp, incandescent like light quality is a big plus, and the amount of lamp waste is minimal.

Additionally, the latest ballasts are now being produced to accommodate multiple wattages and voltages of metal halide lamps.

This also reduces storage requirements, since fewer ballast types need to be kept on hand for timely replacement.

These system improvements are transforming metal halide lamps into the kind of easily interchangeable light source that incandescent A-lamps have been for years. The technology is not quite there yet, but that’s the direction the market is heading.

Lamp Life, Mercury, And Performance

From the facility maintenance point of view, lamp life is an issue that puts fluorescent lamps miles ahead of any other type of light source. Long life T8 lamps have proliferated in recent years, and many product lines from manufacturers are being marketed directly to facility managers.

It’s pretty obvious that the longer a lamp lasts, the less waste is created. However, it’s not an entirely clear cut issue from an environmental waste point of view. T5 lamps, with lower mercury content and less waste potential than T8 lamps, are not yet available in the extended life technology.

 

Low dose mercury lamps have become the norm in recent years, and this translates into very good news in terms of reducing the amount of environmental mercury entering the waste stream. However, some extremely serious issues have resulted from the use of lamps with too little mercury content to support performance requirements.

T5HO lamps that drop below a certain mercury level fail when they are dimmed on a regular basis. Since daylight dimming is one of the bright spots in energy savings for commercial facilities, this indicates that mercury levels in lamps have a critical line below which they cannot fall. As this problem was coming to light over the past couple of years, the number of lamps disposed of due to shortened life was substantial.

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