Just like any manufactured product on the market today, fluorescent lamps are not perfect. Both fluorescent lamps and ballasts fail from a number of factors, even though you might take extensive precautions. A better understanding of why these lighting products fail will make you better prepared for replacing your lighting, and avoiding such issues in the future.

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Predicting these problems ahead of time can be problematic, though. Sometimes you may simply receive a bad batch of products from a distributor. In some cases there might have been an occurrence during the manufacturing process that caused these particular products to fail before their specified lifespan. Or maybe your building experienced a freak electrical surge, on that caused the fluorescent lamp and/or ballast to stop working.

However, if you're knowledgeable about what some of the reasons are for potential issues with fluorescent lamps and ballasts, then you can implement certain practices to try to safeguard against the appearance of many of these issues. Additionally, there is a safety factor to handling broken or malfunctioning fluorescent products. This is mostly due to the fact that fluorescent lamps include a small amount of mercury, a toxic chemical, in them. That’s why it's important to know how to dispose of burned out lamps properly.



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The Lifespan of a Fluorescent Lamp

How long a fluorescent lamp lasts is usually determined by the manufacturer. At ShineRetrofits.com, we carry lamps that last from a little bit under 10,000 hours to over 50,000 hours. There are a number of factors that help determine just how long a fluorescent lamp will operate before giving out such as how it's made, the conditions in which it operates, and the control circuit being used.

A fluorescent lamp that is near the end of its life will normally show a few signs. One clear sign is that the light it emits begins to flicker, which will be annoying enough for you to realize something is wrong. Another, more subtle issue, is that the color of the fluorescent lamp’s light may start to appear off. The fluorescent lamp may also just stop producing light in certain areas of the bulb. Another telltale sign is if either end of the tube turns black.

Why a Fluorescent Lamp May Fail

Failed Electrodes

One part of the fluorescent lamp that might eventually fail are the electrodes (aka filaments or cathodes) that are located at either end of the lamp's tube. When electricity flows into the lamp, those electrodes create an electrical arc from which spring electrons that flow through the gases inside the lamp. They eventually hit the atoms of mercury inside the lamp, causing them to produce wavelengths of UV light. That UV light is then absorbed by the phosphor coating lining the inside of the lamp's tube, and they begin to glow, making the lamp emit light.

If the filaments in the lamp are not working, an electrical current can longer get into the lamp to stir up the necessary electrodes. This means that there is now no heat to turn the mercury liquid inside the lamp into vapor, which is a necessary step In the way a fluorescent lamp emits light.

"Emission Mix"

There is another reason why a fluorescent lamp may fail, which is again related to the electrodes or filaments on either end of the lamp. This time the failure of the fluorescent product concerns what is called the "emission mix", which is located on the filaments and assists in getting the electrons going and moving through the gas inside the lamp's tube. Every time the lamp is turned on and electrons are made, the emission mix is used to help the cathode pass sufficient electrons into the gas. When it runs out of emission mix, though, the fluorescent tube isn’t able to fulfill the electron need, and oftentimes turns black at the ends from overheating and disintegration of the electrodes.  

Now, you may think the more a fluorescent lamp is used, the more mix will be lost. However, it doesn’t necessarily work that way. Every time a fluorescent lamp is turned on in a cold state, more emission mix is used to get the electrons moving through the gas. That means lamps that are switched on for lesser periods of time -- usually less than a three-hour time period -- will find themselves burning out due to less emission mix more than those that are kept on for longer periods of time and aren’t often turned on when in a cold state.

Loss of Phosphors

Eventually, as the lamp is used, the performance of the phosphor coating that lines the insides of the lamp's tube will start to dwindle. You can normally tell this is starting to happen when you notice the light emitted from the lamp is not as bright as it once was. Oftentimes you can tell this when you've installed a new fluorescent lamp next to an older one and can suddenly see the difference in brightness between the two. It’s a slow process, so you can definitely continue to use your fluorescent tube during that time, though eventually, it will become so dim and inefficient as to be useless.

Loss of Mercury

As you know, all fluorescent lamps include a small amount of mercury liquid inside them. And it is this mercury liquid that when formed into a vapor is one of the most important factors in producing light. Over time, as the mercury liquid is changed into a gas, some of that gas will become permanently absorbed into the phosphor coating. Or, the mercury can be even be absorbed by the glass tube itself or the electrodes on either end. 

Since fluorescent lamps are now being made with lower amounts of mercury than in the past, this has now become a much more common problem for the failure of the fixtures. When a fluorescent lamp is beginning to lose its mercury, you can tell by the color of its light, which will begin to look pink.

Disposing of a Fluorescent Lamp

Eventually, all fluorescent lamps fail, which is why it’s important to be knowledgeable about the proper disposal of your lamps. If you find yourself with a fluorescent lamp you now need to dispose of, what's the proper and environmentally-conscious way to do so?

According to the US Environmental Protection Agency, lamps that contain mercury are regulated by the Resource Conservation and Recovery Act (RCRA) Universal Waste Rule (UWR) and Subtitle C hazardous waste regulations. Because of that, there are certain protocols that must be followed when disposing of a fluorescent lamp.

These protocols can also depend on where these fluorescent bulbs are operating. For instance, the EPA has an entire set of rules that must be followed for those handling fluorescent lamps in school buildings. The EPA also has a National Lamp Recycling Outreach program it has developed for the recycling of lamps that contain mercury. Additionally, certain states -- such as California -- have their own rules for how fluorescent lamps should be taken care of. It’s important to be aware of local, regional, and federal regulations for lamp disposal, as they can change depending on where you are and in what context the lamps are being used.

 When it comes to compact fluorescent lamps (CFLs), the EPA also has rules and regulations for these as well. For instance, the EPA recommends CFLs be disposed as hazardous waste rather than in your general household garbage. They also advise recycling CFLs and mention some states -- including California, Minnesota, and Washington -- which require residents to recycle CFLs rather than just throwing them away, where they can be broken in a trash compactor and the mercury inside them released.

Why Ballasts Fail

Another reason why a fluorescent lamp may fail to work is that there's a problem with the ballast. You can tell your ballast may be malfunctioning is if the light begins to diminish or starts to blink at a rapid pace. Another sign can be if the fluorescent lamp stops working very abruptly -- most of the symptoms of a malfunctioning lamp happen over a long period of time, which is why a lamp that just suddenly cuts out may be an indicator of a ballast problem.

 How long the electronics inside the ballast is going to last normally depends on what operating temperature you're using. It's important to check what the minimum and maximum operating temperatures are for the ballast you are using, which are based on what the manufacturer recommends. Generally speaking, if you increase the maximum operating temperature by 10°C, you will lower the ballast's life in half. That can make a huge difference in the monetary cost of replacing your fluorescent lamps and is not recommended.

Additionally, there might be problems if your ballast is not properly wired to the fluorescent lamps, causing it to malfunction. If you find your ballast seems not to be operating at its peak performance, this may be the cause, especially if it's a new installation. Plus, checking in and fixing this is a relatively easy solution, which beats having to replace either your lamp or ballast altogether.

Another tip to remember -- sometimes a ballast has a control inside where if it begins to overheat, it will automatically shut itself off, turning off the light along with it. Then, after it is allowed to cool down for a few minutes, it will turn back on. So before you get rid of your ballast, make sure that's not the issue.

If you have any additional questions about the performance of fluorescent lamps or ballasts, our team at Shine Retrofits would love to help. Our lighting experts know the ins and outs of all our lighting products and can guide you through the process of browsing through and purchasing the best lights and accessories for your project. You can reach us at 1-877-912-4907 anytime Monday through Friday, from 6am to 6pm, Mountain Standard Time. We look forward to hearing from you!