You may or may not have heard of ultraviolet (UV) germicidal radiation to improve home air quality because it has been underused in the residential market. But in an age of multi-drug resistant organisms, bioterrorism, pandemic spread of new viral illnesses, UV light disinfection of the air has been used in hospitals and operating rooms for many years. The fact is, UV lights can be installed in any air conditioning system. If preventing illness is important to you it could be the time has come to consider installing UV light technology in your home.
How Do We Know UV Light Can Protect Your Family From Illness?
In 1862, Louis Pasteur proved that, although unseen, organisms exist and spread contagion suspended in the air. Brilliant 19th century scientists like William Wells wondered if UV radiation from sunlight could control the spread of age-old airborne disease like tuberculosis. Through his research on the bactericidal effect of sunlight Wells discovered how airborne infection is spread by coughing “droplet nuclei” which preserve and suspend bacteria in the air of a closed space and that sunlight kills these bacteria. Niels Finsen won the 1903 Noble Prize for Medicine by proving UV light from the sun could effectively treat tuberculosis of the skin. The same UV light from the sun which causes sunburn and wrinkles, kills or prevents microbes from reproducing by damaging their DNA.
Since those early days, UV lights have been modified for many industrial applications besides disinfecting hospitals. They are used for sterilizing large quantities of water and other liquids; speed drying nail polish and metal bonding agents; and in the food industry to prolong shelf life and reduce food-borne hazards while preserving nutritional value.
Why Worry About Air Quality?
According to the National Center for Biotechnology Information(NCBI), fungal growth in HVAC systems is a common problem which is unwise to ignore. Fungal contamination contributes to chronic inflammation, allergic rhinitis, asthma, hypersensitivity pneumonitis and infectious respiratory disease. This is important if you or your family are susceptible to allergies, have chronic respiratory problems or a weakened immune system- all of which increase the risk for infection.
How Effective is UV Light at Improving Air Quality?
UV light is used to disinfect the surfaces inside of your air conditioning system, such as cooling coils and drip pans. Preventing mold and bacteria growth can reduce maintenance requirements and reduce building related illnesses.
Several studies demonstrate the effectiveness at killing mold and bacteria:
- A 1996 NCBI Study installed UV lights in an office building on certain floors and not on others. For four months they compared the fungal levels on each floor. The UV lights not only reduced fungal contamination within the air handling units and the fiberglass insulation but also reduced levels of airborne fungi in each floor space where they were applied.
- 2. In 2012, researchers at Duke University Medical Center used UV ligt to nearly eliminate drug resistant bacteria in 50 hospital rooms, reducing bacteria counts by more than 97%.
UV light is so effecitive it will improve your indoor air quality by killing mold and bacteria in the air before it recirculates back through your home.
There Are Two Types of UV Light Installation
- Coil Sterilization– This is the most common and most practically priced type of HVAC UV light system. It runs 24-hours-a-day, every day of the week to ensure air sterilization. A “stick-type light assembly is installed inside the supply air duct where it shines on and sterilizes the air handler coil and all surfaces in line-sight of the UV bulb. This installation treats the source of the problem becausee the coil and the drain pan are the source of mold growth and air contamination.
- Air Sterilization– This is used when there is not enough room to install the coil sterilization equipment. It cycles on and off with the air handler blower to sterilize the moving air as it is forced through the system. This will prevent air contaminated from any number of sources from being circulated through your home.
How Much Does It Cost To Run a UV Light System?
It costs about $24 per year in electricity. The bulb should be changed every year to two years, depending on the manufacturer. The bulbs vary in cost from $70-200 also depending on the manufacturer.
Can a UV light Be a Waste of Money?
Yes. While any home or business owner might want to save money with a do-it-yourself UV light install, it is best to hire a trusted professional because poor placement can render the system completely useless. Oasis technicians have the right training and experience to make sure your new UV light system is properly and safely installed.
According to the National Air Duct Cleaners Association the following factors contribute ton the effectiveness of your new UV light system:
- Correct placement and direction of the UV lamps.
- Reflective sheen of the surrounding duct surfaces.
- Optimal ambient home temperature and humidity levels.
Your tech may recommend certain measures to maximize the effectiveness of your UV light system to kill mold and bacteria as well as to eliminate odors:
- Clean and seal all joints to ensure air-tight ducts.
- Assure your HVAC system is designed for the higher static pressure of better filtration of high-MERV filters and install them, if the specs allow.
- Change or wash filters monthly. Use your utility bill as a reminder because when your filters are dirty, your electric bill will be higher.
- Schedule regular seasonal maintenance and clean the coil annually.
UV Light Maintenance
A UV light bulb is estimated to last 9000-1800 hours (1-2 years). Elecricity to run the system will cost about $24 per year. Depending on the manufacturer, the replacement bulb will cost about $70-200. Plan to have the bulb replaced during a routine maintenance visit and you will get the bulb at the best price and get the labor at no additional charge!
Advantages of a Complete UV Light Air Quality System
- Control bacteria, mold, VOCs and odors.
- Reduce colds and flu as germs are not recirculated.
- Reduce clogging in condensate lines by preventing algae growth.
- Improve cooling efficiency and reduce energy costs by keeping the coil cleaner.
UV radiation will eventually degrade exposed non-UV stabilized plastics in line-sight of the air handler such as the drain pan (in 3-5 years) or flex duct (in 2 or more years).
- Carrier Performance Series Germicidal UV Lamps (coil sterilization)
- Fresh-Aire, Triatomic Environmental (coil sterilization)
- Guardian Air REME (coil sterilization)
- Honeywell (coil sterilization)
- Lennox Healthy Climate UVC Germicidal Lights (coil sterilization)
- Sanuvox (air and coil sterilization)
- Top Tech, Air Knight (coil sterilization)