Evaluating Fluorescent Tube Lights – Understanding some important issues
1) Operating life Fluorescent tube lights Versus LED Tube lights
- Standard Fluorescent T8 Light - up to 15,000 hrs
- LED Tube Light - 50,000 hrs - 100,000 hrs
The life of the fluorescent tube depends on the quality of the starter and the ballast. The life span of fluorescent tubes varies between 10,000- 15,000 hours. However there are a few things that you must know.
- A fluorescent tube is exposed to a lot of wear and tear when it is switched on. Estimates suggest that switching on a fluorescent tube once can reduce its life by as much as 20 minutes.
- A faulty starter is a fluorescent tube light’s death knell and must be replaced immediately. It will try to switch on the tube light several times in a minute, drastically reducing its life.
- During the first five minutes of operation a 36 watt fluorescent tube uses close to 50 watts of power. It is often cheaper to let the fluorescent tube burn instead of switching it on and off.
- If you have motion sensors to optimize power usage, it is better to adjust them to switch off fluorescent tube lights only after an area has been unoccupied for 20 minutes.
LED tube lights on the other hand are powered by a ‘Driver’ that supplies a constant low voltage current to the diodes leading to longer life and safer operation.
2) Safety Issues
Fluorescent tubes contain mercury a hazardous material. Mere contact with mercury is sufficient to cause toxic responses. Mercury is such a dangerous neurotoxin that some believe that the phrase ‘mad as a hatter" traces its origin to hats with mercury treated animal pelt lining. These led to absorption of mercury and neurological disorders in the wearer.
Fluorescent tubes must therefore be disposed safely like cans of pesticides and used batteries. Sadly the awareness of the safety issues is lacking. What is worse is that safe disposal facilities may not be available at a convenient location. For people living in the suburbs safe disposal of broken tube lights can at times mean a 20 miles drive.
3) Ultraviolet emission A small amount of UV light is emitted by fluorescent tube lights. The amounts of UV light are minuscule but can still damage artwork and cause complications in predisposed individuals.
4) Ballast
Magnetic ballasts can increase power consumption in a lamp by 10% or more. Electromagnetic ballasts are better but produce a humming sound. High frequency electronic ballasts are the best but cost more than magnetic ballasts thus increasing the cost of lighting projects.
5) Power quality and radio interference
Ballasts have a low power factor and need power factor correction capacitors. Fluorescent tube lights produce harmonic currents in the power supply and the arc can produce radio frequency noise. This renders these lights unsuitable for areas where radio frequency noise is undesirable. While it is possible to suppress the noise the cost of suppression is high.
6) Operating temperature
Fluorescent tube lights work best at room temperature. In cold conditions the temperature may be too low for efficient operation. At temperatures below freezing standard tube lights may not start at all.
7) Flicker problems
A fluorescent tube’s light output and color temperature change constantly. This is what is called ‘Flicker’. Flicker is the reason professional photographers dislike Fluorescent lights. This problem is particularly intensified in tube lights using magnetic ballasts. Even otherwise fluorescent tube lights nearing their end tend to flicker at the frequency of the AC mains. Electronic ballasts can overcome this problem but are more expensive. Cheaper electronic ballasts are available but are likely to interfere with infrared signals.
Energy efficiency, operating life, safety, ease of disposal, worry free performance, flicker free light and versatility -LED devices trump fluorescent lights on every count! So why not buy one today?