What is Ultraviolet (UV)?
Ultraviolet light is electromagnetic radiation with a wavelength shorter than that of visible light. The spectrum consists of electromagnetic waves with frequencies higher than those that humans identify as the color violet (purple).
UV light is typically found as part of the radiation received by the Earth from the Sun. Most humans are aware of the effects of UV through the painful condition of sunburn.
Ultraviolet germicidal irradiation has been studied since the 1930’s and has been used to destroy the microbes that cause indoor air and water pollution. For many years, the medical industry has used UV light to sanitize rooms and equipment. The Centers for Disease Control recommend UV lamps for their germicidal effect.
UV can be separated into various ranges, with short range UV (UV-C) considered “germicidal UV.” At certain wavelengths UV is mutagenic to bacteria, viruses and other micro-organisms. Ultraviolet light is part of the light spectrum, with UV-C from 100 nanometers (nm) – 280 nm; UV-B from 280 nm – 315 nm; and UV-A from 315 nm – 400 nm. Optimum UV germicidal action occurs around 260 nm.
How Does UV Disinfection Work?
UV-C light deactivates the DNA of bacteria, viruses and other pathogens, which destroys their ability to multiply and cause disease. As UV light penetrates through the cell wall and cytoplasmic membrane, it causes a molecular rearrangement of the microorganism’s DNA, which prevents it from reproducing. Specifically, UV-C light causes damage to the nucleic acid of microorganisms by forming covalent bonds between certain adjacent bases in the DNA. The formation of such bonds prevent the DNA from being unzipped for replication, and the organism is unable to reproduce. In fact, when the organism tries to replicate, it dies.
Common Microorganisms Destroyed by UV Light:
- done Bacillus anthracis
- done Corynebacterium diphtheriae
- done Dysentary bacilli (diarrhea)
- done Escherichia coli (diarrhea)
- done Legionella pneumophilia
- done Mycobacterium tuberculosis
- done Pseudomonas aeruginosa
- done Salmonella (food poisoning)
- done Salmonella paratyphi (enteric fever)
- done Salmonella typhosa (typhoid fever)
- done Shigella dysentariae (dysentery)
- done Shigella flexneri (dysentery)
- done Staphylococcus epidermidis
- done Streptococcus faecaelis
- done Vibro commo (cholera)
- done Bacteriophage (E. Coli)
- done Hepatitis
- done Influenza
- done Poliovirus (poliomyelitis)
- done Baker’s yeast
What are the Advantages of UV Disinfection?
- done Environmentally friendly, no dangerous chemicals to handle or store, no problems of overdosing.
- done Universally accepted disinfection system for potable and non-potable water systems.
- done Low initial capital cost as well as reduced operating expenses when compared with similar technologies such as ozone, chlorine, etc.
- done Immediate treatment process, no need for holding tanks, long retention times, etc.
- done Extremely economical, hundreds of gallons may be treated for each penny of operating cost.
- done Low power consumption.
- done No chemicals added to the water supply – no by-products (i.e. chlorine + organics = trihalomethanes).
- done Safe to use.
- done No removal of beneficial minerals.
- done No change in taste, odor, pH or conductivity nor the general chemistry of the water.
- done Automatic operation without special attention or measurement, operator friendly.
- done Simplicity and ease of maintenance, TWT Deposit Control System prevents scale formation of quartz sleeve, annual lamp replacement, no moving parts to wear out.
- done No handling of toxic chemicals, no need for specialized storage requirements, no OHSA requirements.
- done Easy installation, only two water connections and a power connection.
- done More effective against viruses than chlorine.
- done Compatible with all other water processes (i.e., RO, filtration, ion exchange, etc.).
Since natural germicidal UV from the sun is screened out by the earth’s atmosphere, we must look to alternative means of producing UV light. This is accomplished through the conversion of electrical energy in a low pressure mercury vapor “hard glass” quartz lamp. Electrons flow through the ionized mercury vapor between the electrodes of the lamp, which then creates UV light.
Suspended solids or particulate matter can cause a shielding problem in which a microbe may pass through the UV filter without actually having any direct UV penetration. Iron/Manganese will cause staining on the quartz sleeve that houses the UV bulb, at levels as low as 0.3 PPM of iron and 0.05 PPM of manganese. UV filters are best used AFTER adequate sediment, turbidity, iron, and manganese filtration. See our Whole House Water Filter here
Put Ultraviolet light to work for you with your own UV light water treatment system.
99.99% germicidal disinfection against bacteria and viruses!
- done Reduces: Lead, Chlorine, bad tastes, odors
- done NSF tested and certified to Standard 53 for the reduction of Lead and Cysts
- done California Prop 65 certified
- done Ideal for Homes, Office, RV’s and boats
- done Includes dedicated faucet or can be connected to cold water line
304ss chamber, electronic ballast with audible and visual alarm, lamps rated for 30 mj/cm2 @ end of lamp life (9,000 hrs), single lamp per vessel, 3/4 in. MNPT, 110v or 220v.
NOTE: we no longer stock this item. Contact www.watts.com for info.
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