Utraviolet Disinfection Systems
Questions & Answers
Part 1 - What is UV light?
Question: What is UV light?
Answer: UV light is part of the electromagnetic spectrum, shining at a specific wavelength.
All light is given off at different wavelengths. For example if you see a rainbow, you will notice that the colors are always in a specific order from red all the way to blue. You are able to see each color due to their individual wavelength. These wavelengths are part of the visible portion of the electromagnetic spectrum.
UV light is at a wavelength of 254nm (nanometers), and is not visible to the naked eye. This portion of the electromagnetic spectrum is termed UV-C light or a germicidal wavelength. At this 254nm microorganisms undergo a genetic alteration which ultimately results in inactivation.
UV System manufacturers are able to harness this wavelength of light in UV lamps, which will ultimately disinfect your water.
Question: Do I need to disinfect my municipal water supply?
Answer: Our municipalities work very hard to provide safe, disinfected water for their customers. This is quite evident when you consider the difficulties involved in providing safe drinking water through a vast distribution network.
If you use water that comes from a municipal water supply and wish to provide your family with an added "peace of mind", then we believe a UV system acts as an inexpensive insurance policy against the possibility of drinking bacteriologically-contaminated water.
Question: Why do I need to disinfect my water supply?
Answer: Disinfection is recommended for all water supplies that are not protected by a municipal water source (ex. A private well).
Unfortunately, due to the uncertainties that exist with our current water supplies, we can no longer rely on the fact that our water supplies 'may be safe'.
By providing your own disinfection, you are taking the responsibility of ensuring the safety of your water supply for you and your family.
Question: Is UV light harmful?
Answer: You never want to expose your skin or eyes to the light from a UV system. UV light is non-visible however it can be harmful, similar to the harmful effects of UV light from the sun.
UV lamps can actually cause a severe sunburn-like effect if skin is exposed for long periods of time.
Always ensure that you are wearing some type of protective glasses (ie. Safety glasses or sunglasses) when working on a UV system and the lamp is exposed.
You want to make sure that you do not touch the UV lamp with your fingers as the oil from your hands will form a residue on the lamp and can potentially block UV light.
Question: Will UV change the taste and/or odor of my water?
Answer: No. With chemical disinfection, such as chlorination, the taste and odor of your water will change (depending on chlorine levels water can smell and taste of bleach) and disinfection by-products will be produced.
A few examples of chemical disinfection by-products (DBP) are trihalomethanes and haloacetic acid. Both of these DBP's can be carcinogenic when ingested at high levels.
The pH and conductivity of drinking water also changes when chlorine is added.
UV is a physical type of disinfection. This means that the UV will have an effect on the microorganisms in the water only.
The water will not change chemically, nor will the taste and odor change. The water may elevate in temperature if the water has been left stagnant in the UV reactor (ie. During times of little or no use - during the night).
Question: What is UV dose?
Answer: UV dose is the energy that is coming off the UV lamp over a specific time period.
Therefore, UV dose (or fluence) is a product of UV intensity and time. Dose is usually measured in milli joules per square centimeter.
Each Sterilight system is rated to disinfect your water at specific flowrate, under specific water quality conditions to give a UV dose of 30 mJ/cm2 at the end of the lamp life (which is one year).
If you were to run say 10 USGPM through a 5 USGPM Sterilight system (ie. S5Q-PA) then you would only be receiving HALF the dose that the system is rated at because you doubled the flow.
It works the other way as well. If you were to have a 12 USGPM Sterilight system installed (ie. S12Q-PA) but you were only running 6 USGPM through it then you would be receiving double the UV dose as you are increasing the water's exposure time to the UV light.
The UV industry standard for dose is 30 mJ/cm2 at the end of lamp life (EOL) however different validation protocols will specify different dose values.
Question: How does the UV light actually kill microorganisms?
Answer: UV does not kill microorganisms like chlorine does, but instead UV inactivates them. UV light at a specific wavelength of 254 nms i(nanometers) readily absorbed by the genetic material of microorganisms.
The DNA strand is coded with a specific sequence of something called base pairs. The sequence of these base pairs codes for certain characteristics.
UV light at 254 nm is readily absorbed at the point on the microorganism's DNA strand which codes for reproduction.
A microorganism that cannot reproduce, cannot make colonies and therefore cannot infect when consumed. In other words, the microorganisms have been sterilized or neutered. They will eventually die off.
.
Click here for Part 2 - Utraviolet Disinfection Systems
Will a UV system kill all microorganisms in my water?
Click here for Part 3 – Utraviolet Disinfection Systems
Does my water require pretreatment before my UV?
RELATED POSTS:
.
.
Sterilight
Ultraviolet
(UV)
Water Sterilizers
CLICK HERE . . .
ULTRAVIOLET
BACTERICIDAL LAMPS
Trojan, Sterilite, Wonderlite
Multimedia
Filtration
CLICK HERE . . .
.
 |
Multi-Media Filter, Highly-Activated Carbon Filter,
Zeolite-Process Water Softener With Brine Tank,
Fiberglass Ballast-Type Pressure Tank
(fully automatic backwash & regeneration) |
.
PURICARE
INDUSTRIAL
ENTERPRISES
.
...
Aganan, Pavia, Iloilo, Philippines
...
CLICK HERE . . . to view company profile . . .
 |
Reverse Osmosis with Steel Tank
& Cartridge Pre-Filters
|
 |
Tachmina Solenoid-Driven
Chemical Metering Pump
- ensures regulated dosing
of chlorine into water system
without human intervention |
Last night I had a dream. 
along the path of my life,
and most troublesome times of my
life, 
Footprints in the sand
Footprints 
When You Don’t See an End to Your Trials 
Walk With Faith In Your Heart
