| What
is UV?
How does UV work
for water purification?
The UV light
(photons) gets absorbed by the DNA of the pathogen in the water
or liquid being treated. The DNA is altered in such a way that the
pathogen cannot reproduce and is essentially killed and cannot cause
any sickness. This process of DNA modification is called inactivation.
Unlike chemical disinfection the organisms are unable to develop
any immune mechanism against UV light.
How Ultraviolet Disinfection
Works
Just below the smallest wavelength of visible light is a band called
the Ultraviolet Spectrum. The "Germicidal Band" (UVc)
of the Ultraviolet Spectrum is 100 - 280 nanometers. Light at this
wavelength destroys microorganisms including bacteria and viruses.
The WaterFixer operates at 253.7 nanometers, which is the most effective
wavelength for germicidal action. Microorganisms are destroyed by
UV light on contact--this means that UV light must strike the organism
to be effective. Since UV light will not penetrate anything but
a clear liquid, to maintain clarity of your water the WaterFixer
comes with two prefilters.
Prefiltration
The first prefilter screens out larger size substances; the second
filter screens out remaining fine sediment plus chlorine and other
chemicals while eliminating any existing odors or unpleasant tastes
in your water. It also filters parasites such as Giardia and
Cryptosporidium cysts. Inside the 304 stainless steel disinfection
chamber, the ultraviolet bulb is housed in a special quartz sleeve
that allows the bulb to emit energy at the 253.7 nanometers wavelength.
The sterilizing power of the unit is defined by how many microwatts
can be applied to the water per second. At a flow rate of 4 gallons
per minute, the WaterFixer radiates significantly greater energy
than the 16,000 microwatt seconds per square centimeter required
by the U.S. Public Health Service for UV disinfection equipment.
To ensure effectiveness of the ultraviolet component, prefiltration
is mandatory. Only approved filters should be used.
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