Marijuana growth and UV-C.
I work for a prominent UVC company and I’d like to clear up a few things here in this blog if I may…
UVC does in fact have a germicidal property and when used properly can be very helpful to marijuana growers. While many have experimented with direct exposure on growing plants or in a dry room, our research has found that without knowing exact dosages being applied and duration it is hard to nail the sweet spot between “no effect” and “hurting the plant”. We continue to work on defining this but there are so many variables, it is difficult to turn this into a black & white solution for the masses.
We prefer to try to control spore counts through air cleaning the environment of the grow and/or drying room. Our best results have come from 2 practices. Where the plants are inside a facility with central air, we install Very High Power UVC Emitters next to the cooling coil to keep the system from becoming its own breeding ground on the coil and to zap spores on fly-by. Where there is no central air, we have filled rooms with standalone commercial air cleaners either on the floor or suspended above plants. Each machine effectively cleans 1000sq.ft.
UVC does not penetrate. When it hits a surface, it bounces. The dangers of UVC exposure are temporary but in the case of eye exposure can be very painful. It is like a welder’s flash burn. It feels like sand is stuck between your eyelid and eyeball. Typical duration of the irritation is 48-72 hours. Exposure to bare skin can cause reddening like a sunburn but because it does not penetrate, it doesn’t draw melatonin and no tanning will take place. You can itch and get a peeling of the skin in an extreme case but your skin will not turn black and it won’t cause skin cancer.
When measuring UVC dosage, it is measured in “Microwatts per Centimeter Squared” (μW/cm2). The wattage of a lamp has no direct correlation to the dosage of output. Do not compare UVC bulbs by “watts”. Watts is the energy they consume, not the energy they emit. It is the dosage that measures the effectiveness of a delivery vehicle. UVC loses intensity exponentially as it moves away for its source so distance and time of exposure also become factors.
UVV or Vacuum UV light refers to another wavelength in the ultraviolet spectrum. Some UV-C devices also produce light in this wavelength. The manufacturers of these devices promote UVV as an added tool for IAQ control, saying that UVV attacks microorganisms, chemicals, and odors. While this may be true, it is important to understand that UVV (unlike UV-C) will also “attack” occupants in treated spaces by adversely effecting human lungs!
The reason for this is that the shorter (185 nanometers) wavelength of UVV light actually generates ozone. This occurs because UVV light reacts with oxygen to break it into atomic oxygen, a highly unstable atom that combines with oxygen to form O3 (ozone). The American Lung Association states that “exposure to ozone causes a variety of adverse health effects, even at levels below the current standard.” And the U.S. Food & Drug Administration says: “In order for ozone to be effective as a germicide, it must be present in a concentration far greater than that which can be safely tolerated by man and animals.” The longer (253.7 nanometers) wavelength of UV-C light, by contrast, provides highly effective air, surface, and water disinfection without producing any harmful ozone.
The materials and methods of UV-C lamp construction determine whether a given UV-C device will produce both UV-C and UVV light or only the safer UV-C wavelength. Reputable UV-C devices do not produce any UVV.
Bottom line is that correct dosages of UVC applied correctly have shown to be very beneficial to Marijuana growers. UVC use will become more and more accepted as the successful installations we’ve done in the past couple years become more publicized.
Feel free to reach out to me if I can be of further help.