Home Garden

What Are Ultraviolet Mold Lights?

Several approaches exist to prevent and remove mold infestations, one of which is the use of ultraviolet mold lights. Also known as germicidal ultraviolet lights or ultraviolet germicidal irradiation cleaners, these devices use the frequencies of light to destroy mold in your home or building. They can be incorporated into your home's heating, ventilating, and air conditioning (HVAC) system or used as a separate portable device.
  1. Ultraviolet Light Features

    • Ultraviolet molds light use the ultraviolet (UV) light spectrum to destroy unwanted mold. This spectrum ranges from 100 nanometers (nm) to 400 nm. Three different regions exist within the ultraviolet light spectrum. UV-A spectrum ranges from 315 nm to 400 nm. UV-B spectrum ranges from 280 nm to 315 nm. UV-C wavelengths range from 100 nm to 280 nm. The ultraviolet spectrum from 250 nm to 300 is used to destroy mold and bacteria. According to the Scripps Research Institute, 95 percent of UV rays in ultraviolet mold units exist around the 254 nm range, making ultraviolet mold lamps theoretically effective.

    How Do Ultraviolet Mold Lights Work?

    • Ultraviolet mold lights work by destroying mold's cell wall and DNA, according to the Environmental Protection Agency (EPA). This either kills the mold by neutralization or sterilization.

    Considerations

    • Using UV mold lights to kill airborne bacteria may be ineffective, according to Ball State University. Airborne mold spores, whether dead or alive, are capable of inducing allergic reactions. The effectiveness of ultraviolet light also depends on how long mold is exposed to the wavelengths. According to the EPA, in-home ultraviolet mold lights may not be powerful enough to destroy a significant amount of mold. Destroying mold can take anywhere from a few seconds to more than 2 hours, depending on the type of mold present. Another problem is that some mold has become resistant to ultraviolet radiation.

    Prevention/Solution

    • Prevent mold infestation by maintaining low humidity throughout the home. The Centers for Disease Control and Prevention (CDC) suggests humidity levels of between 40 percent and 60 percent. In addition to UV mold lights, a good filtration system, preferably a High Efficiency Particulate Air (HEPA) system, is needed to remove the spores from the air and prevent potential allergenic responses. To remove mold growth from hard surface, use a commercial solution or a bleach solution containing 1 cup of bleach and 1 gallon of water, suggests the CDC. When using a bleach solution, open the windows to circulate air.