Mercury in CFL Bulbs: Is It Dangerous?

Aug 31, 12 Mercury in CFL Bulbs: Is It Dangerous?

Lighting topics don’t get much more exciting than the debate over the mercury content of compact fluorescents (CFLs). Those against the use of CFLs claim that the potential harm of toxic mercury contained within the energy-saving bulbs far outweighs any environmental benefits. On the other side, groups feel such rhetoric is overblown. But what are the facts?


Why Use Mercury in CFLs?

Mercury (Hg) is a naturally occurring element used in applications as varied as thermometers, dental fillings, and fluorescent lighting. The cathodes within a fluorescent tube produce electric current that passes through argon gas and mercury vapor. In turn, the mercury vapor emits ultraviolet light that excites the phosphor coating within the fluorescent tube, producing visible light [1]. The technology is the same for both linear fluorescent tubes (like those seen in office buildings) and self-ballasted compact fluorescents (the “spiral” bulbs used in homes). In short, without mercury, fluorescent lights will not work.


How Much Mercury is in a CFL?

The amount of mercury contained within a CFL varies, and in general, has decreased since their introduction nearly two decades ago. As of November 2010, the US EPA’s Energy Star program concluded that the average amount of mercury within a screw-in CFL was 4 milligrams, comparable to the size of a ballpoint pen tip [2]. This pales in comparison to older thermometers, which contain as much as 500 mg [3] and even amalgam dental fillings, which contain about 100 mg of mercury [4].

Mercury Content

Mercury Content in Popular Items

Keep in mind, however, that the mercury contained in a CFL, thermometer, or dental filling can be present in these sources in two forms: A liquid, which is what we typically think of when we think of mercury, and a vapor that quickly dissipates. In the case of a broken CFL, the most likely form of exposure comes from inhaled mercury vapor. A paper in the August 2009 issue of the lighting journal LD+A found that the median amount of mercury vapor to which a person is exposed through a broken CFL is a tiny fraction of the total mercury contained within the bulb: Approximately 0.07 micrograms (0.0007 mg). On the other hand, a tuna fish sandwich, which contains the more hazardous methylmercury, is estimated to expose the consumer to more than 48 times that amount due to the more efficient method of consumption (literally eating the mercury) [5].


Who Regulates Mercury in CFLs?

Despite its relatively low concentration in CFLs, mercury is still a toxic substance. For this reason, the EPA requires that CFLs contain no more than 5 mg of mercury for consideration in their Energy Star program. The European Union and the State of California adopted even tougher regulations, requiring CFLs to contain no more than 2.5 mg of mercury by 2013 [6]. Manufacturers, however, have made the biggest strides. A 60-watt equal, warm white Neolite CFL by Litetronics, for example, uses only 1 mg of mercury, 80% less than Energy Star requirements [7]. Along with other major manufacturers, Sylvania voluntarily capped CFL mercury content at 4 mg, with the 13-watt DULUX EL 29409 containing only 1.5 mg [8].


The Answer?

So the question remains: Is the mercury in CFLs dangerous? It’s not an easy question to answer. Mercury is a toxic substance, yet it is unlikely that fluorescent lighting would ever expose a person to an amount of the neurotoxin sufficient to cause physiological harm. Want proof of that? Despite putting themselves in a worst-case scenario fluorescent lighting mishap, to the best of our knowledge, these two guys are still alive and well:



1. Van Dussen, Matthew. ‘The Mercury Myth: How Much Mercury Do CFLs Actually Contain?’ TXNOLOGIST. Retrieved 2012-08-30.

2. ‘Frequently Asked Questions: Information on Compact Fluorescent Light Bulbs (CFLs) and Mercury’. Energy Star. Retrieved 2012-08-30.

3. ‘Indoor Liquid Mercury Spills: Frequently Asked Questions’. State of Michigan. Retrieved 2012-08-30.

4. ‘IMERC Fact Sheet: Mercury Use in Dental Amalgam’. NEWMOA. Retrieved 2012-08-30.

5. Clear, Robert et al. ‘Dangerous Mercury in CFLs? One Big Fish Story’. LD+A. Retrieved 2012-08-30.

6. (2)

7. Litetronics Neolite Sell Sheet. Retrieved 2012-08-30.

8. ‘Mercury Quantity in Lamps for General Lighting Applications’. Sylvania. Retrieved 2012-08-30.

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How to Choose Landscape Lighting

Apr 27, 12 How to Choose Landscape Lighting

Most homeowners install landscape lighting for safety concerns. For example, we put PAR38 Halogens above our garages and entrances so we can see at night and detect intruders. Others may install inexpensive solar powered LED lights to line their sidewalks or flower beds. However, these applications fall far short of what is possible with landscape lighting.

During the day, your neighbors see everything touched by the sun, but at night, you’re given a blank canvas that you can “paint” with the right lighting design. When used thoughtfully, landscape lighting can have a transformative effect on your lawn, highlighting focal points and adding dimension to your yard.

To begin your project, decide between solar and low voltage landscape lighting. Line voltage landscape lighting is also available, but is only recommended for large commercial applications. Solar lighting is inexpensive, easy to install, and doesn’t use any electricity since it derives all its power from the photovoltaic panels on the fixture. However, solar lights are undependable. Solar landscape lights are dim and produce light for only a few hours. For this reason, doesn’t carry solar landscape lights, nor do we recommend them. Instead, we suggest low voltage landscape lights that operate at either 12 or 24 volts. When used with the right outdoor transformer, low voltage lights are safe, easy to install, and even easier to maintain.

Next, you have the choice of Halogen or LED landscape lights. Halogen landscape lights are the traditional type of landscape lighting. They are relatively inexpensive, yet they use a large amount of electricity. The advantage of LED is huge energy savings, though your up-front cost may be much more. A typical Halogen landscape bullet, for example, can use as much as 60 watts, but an LED of the same brightness will use only 10. LED lights will also last 50 times as long as Halogen; this means significant long-term savings and much less maintenance.

Now design your landscape lighting layout. On the typical home, you’ll need three types of lights: Pathway lightsbullet lights, and in-ground well lights. Pathway lights, as the name implies, go along pathways, including sidewalks and driveways. You can install bullet lights in the ground and pointed upward to highlight trees, bushes, statues, fountains, and building facades. You can also install bullet lights pointing downward from trees, which makes the tree look full and vibrant while casting a soft glow over your entire yard. Finally, you can use well lights in many of the same areas as bullet lights. Because they are buried, well lights are more concealed, making them perfect for spotlighting trees where there isn’t any other foliage around to hide a bullet light.

So have you installed or considered installing landscape lights at your home? If you’ve already installed them, what are your experiences? If you haven’t, what type of landscape lights most interest you? Drop us a line in the comments below, or give us a holler on Facebook, Twitter, or Google+. You can even post your project photos on Pinterest!

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Exit and Safety Lights

Oct 19, 11 Exit and Safety Lights

If you own or manage a business of any sort, it is likely required that you invest in exit lights, safety lights, and emergency signage. While no business owner wants to think his or her business might suffer a fire or other emergency, it is important to prepare for that contingency anyway. Insurance companies demand it, and most local fire codes make it a requirement. Most importantly, however, proper emergency lighting is for the safety of your business, customers, and suppliers. The last thing you want is for a simple lack of signage or emergency lighting to lead to a tragic accident.

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Cyalume Glow Sticks

Aug 22, 11 Cyalume Glow Sticks

As a form of recreational light, “glow sticks” are popular options for children who go out trick-or-treating on Halloween and are fun options at parties and other recreational events. However, they have many practical uses as well. They are great options for safety lighting and are popular devices for the military, law enforcement, and other emergency personnel. They are useful for signaling, illumination, surveying, perimeter control, and many other uses. Cyalume safety products has taken advantage of the glow stick’s potential as a safety product by creating a line of industrial and military-grade chemiluminescent “Lightbars.”

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Smoke Alarm Safety

Mar 14, 11 Smoke Alarm Safety

House fires happen. That’s an unfortunate fact of life. Most people know that in order to keep their families and homes as safe as possible, they need to have a smoke detector in every bedroom, every major room, and in the hallways leading to rooms and bedrooms. This, of course, allows you to hear the alarm if a fire breaks out, even when you are sleeping. However, not everyone knows that fire alarms need occasional maintenance.

Most household smoke detectors installed today use a battery backup in case of a power loss. These batteries need to be checked or replaced on a regular basis, twice a year according to most experts, so what better opportunity than daylight saving time to do those quick checks? Next time you change your household clocks, check your smoke detector batteries as well. If there is any doubt that the battery is fresh, throw it out and replace it with a new one. Another good idea is to switch from standard alkaline batteries to Lithium batteries. Lithium batteries can be more expensive, but they can also last up to ten years, saving money in the long run and keeping your home safer.

You may also use this time to determine whether your home is as safe as it could be. Sure, you may have the best smoke detectors installed in all the right places, but what happens if you have a Carbon Monoxide leak? Carbon Monoxide (CO) is known as the silent killer because it is an odorless, colorless, tasteless gas which can go undetected by humans. While even the human body uses this natural substance to some extent, high levels of carbon monoxide starve the body of oxygen and can be just as dangerous as a fire. Many detectors today combine both smoke detection and carbon monoxide detection, but they can also be installed separately, depending on your specific needs.

Don’t let this year’s “spring forward” be such a drag. Use the time change to your family’s advantage and test that your smoke detectors are working and have fresh batteries and even consider installing Carbon Monoxide detectors. You can get detectors as well as a good supply of batteries here at at below retail prices.

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