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Questions and Answers
About Compact Fluorescent Lamps (CFLs)

Safety

I have heard that there is mercury in CFLs,
is this true?

Should I be concerned about using CFLs
in my home?

What would the health risks be if a CFL
breaks in my home?

What should I do if a CFL breaks?
What does the mercury in a CFL look like?

Comparison with Incandescent Bulbs

When I replace my incandescent lamp with a CFL, and the fixture indicates a maximum wattage of 60 or 40 watts, should I worry about using a CFL with a lower wattage than recommended?
Is there a CFL equivalent to an incandescent tri-light of 50-100-150?
Is a CFL harder on the eyes than an incandescent light?
Why do CFLs use less energy than incandescent bulbs?
How do I compare incandescent light bulbs with CFLs?

Cost and Savings

What accounts for the price difference in CFLs?
Why should I buy a CFL?
Why are CFLs more expensive?
How much will I save by using CFLs?
Do CFLs work with dimmers and three-way switches?
Why choose an ENERGY STAR® qualified CFL?

Use and Location

Are there spiral CFLs that can be used for plants as a source of light?
How does a CFLs perform in areas where power surges occur, such as rural areas?
Does the wattage indicated on the package of a CFL include the wattage necessary to run the ballast?
Aren't fluorescent lights just for offices?
Where can I install CFLs?

Safety

I have heard that there is mercury in CFLs. Is this true?

There is a small amount of mercury in CFLs to help them produce light. But this amount is less than one fifth the amount found in a common watch battery. The mercury in a CFL is used to create the light and is totally contained in the fluorescent tube. This chart compares the mercury content in CFLs and in other uses:

Mercury Content Comparisons
Product Amount of Mercury Number of
Equivalent CFLs
CFL 5 milligrams 1
Watch battery 25 milligrams 5
Dental amalgams 500 milligrams 100
Home thermometer 500 milligrams to 2 grams 100—400
Float switches
in sump pumps
2 grams 400
Tilt thermostat 3 grams 600
Electrical tilt switches
and relays
3.5 grams 700

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Should I be concerned about using CFLs in my home?

CFLs are safe in your home. No mercury is released when the bulbs are in use, and they pose no danger to you or your family when handled properly. An extremely small amount of mercury, an average of five milligrams, is sealed within the glass tubing. For a basis of comparison, there are about 500 milligrams to two grams of mercury in your average home thermometer. It would take from 100 to 400 CFLs to equal that same amount of mercury!

What would the health risks be if a CFL breaks in my home?

Actually, your greatest health risk is being cut from glass shards. Because there is such a small amount of mercury in CFLs, research indicates that there is no immediate health risk to you or your family should the bulb break, especially if cleaned up properly.

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What should I do if a CFL breaks?

In the unlikely event your bulb breaks, be certain to sweep up – don't vacuum – all of the glass fragments and phosphor powder. Place the broken pieces in a plastic bag and wipe the area with a damp paper towel to pick up any stray shards of glass or fine particles. Put the used towel in the plastic bag as well. Like paint, batteries, thermostats and other hazardous household items, CFLs should be disposed of properly. Check with your municipal waste management program for proper disposal. If there is no such program, place in a regular waste container. It is good practice always to clean up any products containing mercury with care and common sense.

What does the mercury in a CFL look like?

It may be difficult to see the mercury for several reasons. Simply put, there's just not much there to begin with. Five milligrams – the average amount in a CFL – is about the size of the tip a ballpoint pen. Additionally, the mercury will be in vapour form or absorbed on the lamp walls, the metal lamp ends or other bulb components. At the end of a bulb's rated life, very little of the mercury is available for release into the environment.

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Comparison With Incandescent Bulbs

When I replace my incandescent lamp with a CFL, and the fixture indicates a maximum wattage of 60 or 40 watts, should I worry about using a CFL with a lower wattage than recommended?

No. There is no minimum value for the wattage used in these fixtures, only a maximum. Consult the wattage equivalency chart to keep the same light output (measured in lumens) or to increase it, depending on your needs.

Is there a CFL equivalent to an incandescent tri-light of 50-100-150?

Yes, but the wattage equivalency for a specific CFL may vary slightly between manufacturers. Besides, there are different ranges of wattage for CFL tri-lights.

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Is a CFL harder on the eyes than an incandescent light?

No. Some of the older models of fluorescent tubes would sometimes flicker and cause some people to have headaches. However, the light emitted by a CFL is very much like that of an incandescent. This does not change the fact that the "lumen" output of equivalent products is the same.

Why do CFLs use less energy than incandescent bulbs?

Fluorescent technology is much more efficient at converting energy to light. Standard incandescent bulbs, which have been produced the same way using the same materials for more than 100 years, use at least 90 percent of their energy to produce heat, not light.

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How do I compare incandescent light bulbs with CFLs?

The packaging for ENERGY STAR® qualified CFLs will give you all the information you need to make a true comparison with other bulbs. On each package, look for:

On each package, look for:

  • the amount of light produced by each bulb, measured in lumens
  • the average expected life of the bulb in hours
  • the wattage of the bulb
  • the wattage of an equivalent incandescent bulb

Remember, the wattage rating listed on light-bulb packaging is a measure of the power used, not the light output. CFLs use much less energy to deliver the same light output as incandescent bulbs.

Cost and Savings

What accounts for the price difference in CFLs?

CFLs come in a wide range of designs and shapes, and some are specifically made for tri-lights and dimmers. Prices may vary according to these characteristics and according to the manufacturer.

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Why should I buy a compact fluorescent light bulb?

You will save energy. CFLs use only one quarter of the energy of standard incandescent bulbs. A 15-watt CFL produces the same high-quality light as a typical 60-watt incandescent bulb and saves 45 watts for every hour you leave the light on.

Why are CFLs more expensive?

CFLs are a better product. Production costs for CFLs have dropped a great deal in the last 10 years, and manufacturers and retailers are passing these reductions on to consumers. But CFLs still cost more because they are more expensive to make than standard incandescent bulbs. The CFL manufacturing process is more complex, requiring more electronic materials and higher product-inspection and quality-control costs.

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How much will I save by using CFLs?

An average Canadian home has 30 light fixtures, indoors and out, that consume close to $200 of electricity every year. Replacing just five bulbs with ENERGY STAR qualified CFLs in high-use areas can save up to $30 a year, depending on location and amount of time used. That means you'll pay off the added cost of the bulbs in less than two years, and they last for at least five. Better still, you won't have to change them as often.

Do CFLs work with dimmers and three-way switches?

Some CFLs are specially designed to work with dimmers and three-way switches. Check the package to make sure.

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Why choose an ENERGY STAR qualified CFL?

On CFLs, the ENERGY STAR symbol means that the product meets strict specifications for quality, including long life, colour and brightness, as well as energy savings.

Use and Location

Are there spiral CFLs that can be used for plants as a source of light?

Yes. Some CFLs are specifically designed to provide natural light to indoor plants; their light output contains blue, green, red and orange spectrums to promote plant growth.

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How does a CFL perform in areas where power surges occur, such as rural areas?

CFLs may not hold up to the stress of power surges. So using them in these areas may not be advisable.

Does the wattage indicated on the package of a CFL include the wattage necessary to run the ballast?

Yes.

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Aren't fluorescent lights just for offices?

Not any more! Thanks to a number of technological advances in recent years, ENERGY STAR qualified CFLs are a great choice for your home as well. They come in a range of designs and shapes to fit almost any fixture, indoors and out. CFLs can provide warm light for a living room or brighten up a workspace. And they don't flicker or hum like fluorescent lights of the past.

Where can I install CFLs?

They can be installed indoors or outdoors. The package will tell you where the CFL can be used. You'll find CFLs to fit almost all fixtures, from ceiling units to standing lamps. A good idea is to start installing CFLs in areas where lights are on longest, such as the kitchen, family room and outdoors. Because CFLs don't have to be changed as often, many people install them in hard-to-reach areas.

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