Germicidal ultraviolet (UV) lights are used in scientific procedures and air-conditioning systems to kill microorganisms both in the air and on nearby surfaces. The lights use unique bulbs that produce c-type ultraviolet wavelengths, which are dangerous to living organisms and fatal to those small enough to float through the air with dust particulates. There are both benefits and problems involved in using UV lights.
• UV lights are useful because of their effectiveness. As long as the air is not passing dust particles through the filters at speeds too high for the light to be effective, the UV lamp can kill over 99 percent of any microorganisms in the air, including bacteria, viruses and mold spores. Few other filters can match their effectiveness.
• Some ultraviolet filters are placed directly above air-conditioning systems to kill any microorganisms near the heat or cooling coils of the system. This keeps the system from develop mold problems, and with an additional filter, also helps prevent the collection of dust. In turn, the air-conditioning system can run more efficiently, saving energy.
• There are several different types of UV filter lights, and they can be placed not only over air-conditioning systems, but inside vents and even in rooms as stand-alone units. The lamps must be shielded from people, but they do provide an easy way to disinfect rooms that are not part of the air-conditioning system and cannot easily vent out contaminants.
• Dust creates another problem for the UV lights. As it passes in front of the bulb, it collects on the bulb’s surface. Over time, this lowers the effectiveness of the bulb, which must be wiped clean frequently in dusty environments. Because of the danger to people, the UV system must be fully shut down before anyone can conduct any maintenance.
Benefits of using a UV Light system in your heating and cooling ducts are numerous, and we will get into an explanation of how this wonderful technology is significantly helping:
• UV light systems are an eco-friendly way of controlling pathogens. Ultraviolet light kills fungi and bacteria without requiring biocides and toxic chemicals. Some UV light systems also produce ozone, another eco-friendly way of killing viruses, bacteria and mold.
• A UV light system can be added to your HVAC system without any costly or major changes while improving the quality of your air. UV lights can be placed in the air supply ducts or the return ducts. Or the UV light can be located in the air conditioner plenum.
• UV light systems kill bacteria and viruses that are too small to be caught by conventional air filters.
• A UV light system is an invaluable addition for those who have respiratory conditions or long term illnesses. For someone with a depressed immune system, installing a UV light system ensures that they do not become ill due to mold growing in the air duct or from bacteria that may live inside the ducts. UV light systems also help ensure that the germs expelled by someone coughing in one room do not spread through the ducts to another.
• UV light systems kill the bacteria that cause tuberculosis. If someone in your home is an asymptomatic carrier of tuberculosis or is infected, you must have a UV light system installed in your HVAC system to minimize the risk to other family members.
• Unlike air filtration units, UV lights are essentially maintenance free. You only need to replace the bulbs when they burn out.
• Unlike the addition of air filters, UV lights clean your air without forcing the HVAC system to work harder to distribute air through the home.
• If you use a UV light system in place of other air filtration and purification devices, you may save electricity. For example, a single UV light system can clean the air in a one thousand to two thousand square foot home. If you then shut down the room sized air filtration units, you’ll save energy.
Many things can affect the quality of the air that we breathe in on a second to second basis and we don’t always have to live near a smokestack factory for it to be bad. It’s interesting how our liking for having control over the temperatures inside our homes is also creating some unintended negative effects. Indoor air pollution is a result of allergens, bad odors and microorganisms – all swirling around in that circulated air inside our homes, which incidentally, are built better or “tighter” these days and keep all those things from escaping.
On Sanibel and Captiva Islands, where we have more water than land, mold spores growing from excessive moisture can pose a significant health threat. Excessive moisture can build up from storm water damage, leaking pipes or in poorly ventilated areas. Also, leaving a home unused for a long period of time can provide the perfect environment for mold growth.
Mold spores have been known to survive extreme temperatures, float through the air indefinitely or cling to our clothing or a pet’s fur. While there are many species of mold, some are even famous for being used for medicinal purposes, a few of them like to grow in our homes and are linked to a variety of health risks. They can cause allergic reactions, chronic respiratory illnesses and some, but only a few, can actually be toxic.
I’m not trying to scare you, it’s just that it’s a common concern that we receive a number of calls about.
A good solution to a mold issue is to begin with an effective clean-up, which isn’t always cheap. Mold damage can be difficult to contain, but what would be even more effective, is looking into prevention. It’s a good idea to regularly inspect your air conditioning system and make sure that it’s in great shape. You can also consider putting in some add-on features that could help you keep the air clean of spores.
A very simple and relatively inexpensive method is to install a UV light inside the air handler. They’re safe, prevent expensive chemical clean-ups and don’t cost more than energy-efficient fluorescent lights to operate.
We all love and greatly benefit from the natural effect of sunlight. Sunlight also serves as one of the best air purification systems around, and to an extent, it does help purify our indoor environment – entering through the windows and doors. The problem lies in the areas in our home that are never exposed to sunlight. Being an air conditioning contractor, I am of course speaking of your home’s comfort system. The air handler meets all of the requirements to be a great breeding ground for microorganisms. It’s dark, it’s moist and contains a constant food source to help these little “nasties” grow.
The sun’s ultraviolet C wave is the one that produces the light that is nature’s own sterilizer – perfect for cleansing the air. It has been scientifically proven to penetrate microorganism structure, disrupt their DNA and prevent them from breeding. By utilizing artificial ultraviolet light, humans have been able to mimic the sun’s ability and use it for germicidal irradiation. The practice has been used by food and wastewater industries since the 20th century and more recently, has found its way into air purification. The World Health Organization states that biological contaminates account for 50% of all home allergies. Artificial ultraviolet lights can be installed by an air conditioning contractor and help the sun shine where it normally doesn’t.