Frequently Asked Questions - Compact Fluorescent (CFL)
1. Can I use a compact fluorescent light bulb with
an electronic timer or photocell (AKA electric eye)?
Be sure to check the lamp package, which will indicate if the
lamp is not intended for use with electronic timers or photocells.
Some electronic timers and photocells contain parts that are
incompatible with compact fluorescent light bulbs; using these
bulbs in incompatible products will result in a shorter light
bulb life. To find out if an electronic timer or photocell is
compatible with compact fluorescent bulbs, check with the manufacturer
of the timer or photocell.
2. Can I use a compact fluorescent light bulb in
an enclosed light fixture?
Compact fluorescent light bulbs may generally be used in enclosed
fixtures as long as the enclosed fixture is not recessed. Totally
enclosed recessed fixtures (for example, a ceiling can light
with a cover over the bulb) create temperatures that are too
high to allow the use of a compact fluorescent bulb.
Many CFLs can be used outdoors in an enclosed fixture. Check
the lamp or package to make sure it is approved for outdoor use,
and verify the lowest operating temperature for the area where
the product is being used. If the lamp or package does not state
it can be used outdoors, then it is not approved for outdoor
use, even in an enclosed fixture.
3. Can I use a compact fluorescent light bulb with
a dimmer switch?
To use a compact fluorescent bulb on a dimmer switch, you must
buy a bulb that's specifically made to work with dimmers (check
the package). We don't recommend using regular compact fluorescent
bulbs with dimming switches, since this can shorten bulb life.
4. Can I use a CFL in applications where I will
be turning the lights on/off frequently?
Compact fluorescent light bulbs work best if they are left on
for over 15 minutes each time they are turned on. These types
of lamps can take up to 3 minutes to warm-up. Warm-up will probably
not be noticeable from a user stand point, but the lamp needs
to warm-up in order to reach the point of most efficient operation.
Frequently switching them on and off will shorten the life of
the product. If the life of the lamp is shortened significantly,
you will not reap the financial benefits (includes energy & life
of lamp), that are common to CFL lamps.
5. Can I use a CFL in applications involving vibration
such as a ceiling fan or garage door opener?
Currently it is not recommended to use CFLs in vibrating environments.
Vibration can cause the electronics in the CFL to fail.
6. What should I do if I break a CFL bulb?
Fluorescent lamps contain mercury. Mercury at atmospheric pressure
is a silver colored liquid that tends to form balls. Mercury
is a hazardous substance. When one lamp is broken, the best thing
to do is to wear chemical resistant glove to clean it up. The
gloves can be vinyl, rubber, PVC, or neoprene. The gloves you
buy in the supermarket for household cleaning are sufficient.
The gloves protect your skin from absorbing mercury and from
getting cut by the glass. The remains of one lamp can be disposed
as normal waste since the amount of mercury is small. However,
for future reference, when large quantities of lamps are being
disposed you must follow your state and the federal regulation
for disposing of mercury-containing lamps.
7. Why does the color of CFLs seem different
at start-up?
The variation in lamp color at start-up of the lamp is a result
of phosphor activation. Phosphor is the coating on the inside
of the bulb that glows when bulb has an electrical charge to
give the lamp a "white" light effect. Different phosphor combinations
produce different colors and may have slightly different response
times. These differences are why the lamp sometimes looks pink
or purple when you start it.
8. Do light bulbs (such as fluorescent and compact
fluorescent bulbs) give off hazardous amounts of ultraviolet
(UV) light?
Regular fluorescent light bulbs used in your home and office
do not produce a hazardous amount of ultraviolet light (UV).
Most light sources, including fluorescent bulbs, emit a small
amount of UV, but the UV produced by fluorescent light bulbs
is far less than the amount produced by natural daylight. (Ultraviolet
light rays are the light wavelengths that can cause sunburn and
skin damage.)
Your safety is important to us. That's why, for all of our light
bulbs designed for general public use, we strive to minimize
the amount of UV light emitted.
If you're looking for a low-UV bulb for an especially sensitive
area, try our Saf-T-Gard® bulbs. They block most ultraviolet
light emissions, and they're also shatter-resistant.
9. How does a compact fluorescent light bulb work?
Fluorescent light bulbs (including compact fluorescents) are
more energy-efficient than regular bulbs because of the different
method they use to produce light. Regular bulbs (also known as
incandescent bulbs) create light by heating a filament inside
the bulb; the heat makes the filament white-hot, producing the
light that you see. A lot of the energy used to create the heat
that lights an incandescent bulb is wasted. A fluorescent bulb,
on the other hand, contains a gas that produces invisible ultraviolet
light (UV) when the gas is excited by electricity. The UV light
hits the white coating inside the fluorescent bulb and the coating
changes it into light you can see. Because fluorescent bulbs
don't use heat to create light, they are far more energy-efficient
than regular incandescent bulbs.
10. What compact fluorescent light bulb do
I buy to replace a 60-, 75-, 100- or 150-watt regular bulb?
While a regular (incandescent) light bulb uses heat to produce
light, a fluorescent bulb creates light using an entirely different
method that is far more energy-efficient - in fact, 4-6 times
more efficient. This means that you can buy a 15-watt compact
fluorescent bulb that produces the same amount of light as a
60-watt regular incandescent bulb. Plus fluorescent light bulbs
last up to 13 times longer and use 2/3 to 3/4 less electricity
than incandescent bulbs with similar lumen ratings.
Here are the watts needed by regular incandescent bulbs and
compact fluorescent bulbs to produce the same amount of light.
- 20 watts incandescent = 5 watts compact fluorescent
- 28 watts incandescent = 7 watts compact fluorescent
- 36 watts incandescent = 9 watts compact fluorescent
- 40 watts incandescent = 10 watts compact fluorescent
- 52 watts incandescent = 13 watts compact fluorescent
- 60 watts incandescent = 15 watts compact fluorescent
- 75 watts incandescent = 20 watts compact fluorescent
- 100 watts incandescent = 26-29 watts compact fluorescent
- 150 watts incandescent = 38-42 watts compact fluorescent
- 250-300 watts incandescent = 55 watts compact fluorescent
11. How much heat (or infrared radiation) is emitted
by regular, halogen, and compact fluorescent light bulbs?
Because incandescent and halogen bulbs create light through
heat, about 90% of the energy they emit is in the form of heat
(also called infrared radiation). To reduce the heat emitted
by regular incandescent and halogen light bulbs, use a lower
watt bulb (like 60 watts instead of 100).
Fluorescent light bulbs use an entirely different method to
create light. Both compact fluorescent bulbs and fluorescent
tubes contain a gas that, when excited by electricity, hits a
coating inside the fluorescent bulb and emits light. (This makes
them far more energy-efficient than regular incandescent bulbs.)
The fluorescent bulbs used in your home emit only around 30%
of their energy in heat, making them far cooler.
