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Fluorescent Lighting - Ballasts: Why You Should Upgrade
Ballasts are an essential component of any fluorescent lighting system, providing a controlled current to the fluorescent tubes. In an office or industrial setting, the standard type of ballast used for the last few decades is an electro-magnetic type, which unfortunately produces a number of negative side-effects:
They operate at 60Hz, or cycles per second - the frequency of the AC voltage they run on. This means that each lamp switches on and off 120 times per second, resulting in a barely perceptible flicker and a noticeable hum (sounding like a buzzing low ‘A’ note on a piano). About 25% of the population is sensitive to ballast flicker and hum and actually can become physically ill, with symptoms such as headaches, nausea, itching and burning eyes, tension, eye fatigue, and general fatigue.
Operating at 60Hz, they may cause a stroboscopic effect with any machinery which has parts, such as pulleys or gears, running at speeds that are a multiple of 60Hz. The stroboscopic effect will cause the machine to appear motionless, which could be a deadly hazard.
The most commonly used electro-magnetic ballast, the rapid-start type, draws 2-3 watts even if the lamp is switched off, a sizable expense in a building with many lamps. This ballast draws current even if the fluorescent tubes are removed.
They give off excessive EMF (Electro-Magnetic Fields), considered a potential cancer-causing agent.
Any of the electro-magnetic ballasts produced prior to 1978 contain PCB’s - a known carcinogen.
Not energy-efficient, with a relatively short life span of about 10 years.
During the final 30% of their lifespan they consume the same amount of energy, while producing far lower light levels.
In recent years, a new solid-state electronic ballast has become available to the American market. This ballast is lightweight, generates very little heat, and operates at about 25,000Hz, rather than the standard 60Hz. This last detail, high frequency operation, effectively eliminates all flicker and hum, removing any associated health concerns.
Some of the advantages of the solid state electronic ballast:
Excellent energy efficiency. Produces more light, while using 25-30% less energy. This, coupled with rebate programs being offered by most utilities, makes upgrading all ballasts a very cost-effective move.
When switching to these ballasts, it is also necessary to change to T-8 fluorescent tubes, which are a full-spectrum type – providing excellent, daylight-like color rendering.
These ballasts can also be purchased in a type which are dimmable, enabling office users to lower light to personal comfort levels, which will pay off in further energy savings. This is highly recommended, where practical, in any office environment.
High frequency operation eliminates bothersome flicker and hum, improving the work environment and saving the company untold hours of lost sick time and worker fatigue.
Very low EMF emissions.
Long life - these ballasts and their fluorescent tubes will double the lifespan of their older counterparts, reducing associated maintenance costs.
To verify which type of ballast is currently installed in a given fixture, without having to take it apart, a flicker checker is available through Motorola (call 1-800-453-1506 for information on obtaining this inexpensive tool, known as a flicker checker device [FCD]). Spin the flicker checker on a flat surface underneath the fluorescent lamp in question. If the ballast is the older, electro-magnetic type, you will see a stroboscopic effect appear as it spins. If the fixture has the high-frequency, electronic type ballast, you will see no effect on the flicker checker.
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"Information or recommendations contained in these articles were obtained from sources believed to be reliable at the date of publication. Information is only advisory and does not presume to be exhaustive or inclusive of all workplace hazards or situations."
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The above evaluations and/or recommendations are for general guidance only and should not be relied upon for legal compliance purposes. They are based solely on the information provided to us and relate only to those conditions specifically discussed. We do not make any warranty, expressed or implied, that your workplace is safe or healthful or that it complies with all laws, regulations or standards.
