1. What is ultraviolet (UV) light?
Ultraviolet (UV) light represents one portion of the sun's electromagnetic spectrum. It is the wavelength shorter than that of visible light, but longer than x-rays, in the range 10 nm to 400 nm, and energies from 3 eV to 124 eV. It is so named because the spectrum consists of electromagnetic waves with frequencies higher than those that humans identify as the color violet.
Most people are aware of the effects of UV through sunburn, but the UV spectrum has many other effects, both beneficial and damaging, on human health.
2. How is UV light used to sterilize water?
An electric arc, struck the length of the lamp, travels through an inert gas. The UV light passes through a special quartz glass which is placed in the water current. The water flows around the UV lamp exposing any microorganisms, viruses, bacteria and/or algae to a lethal dose of UV light.
Ultraviolet light penetrates the cell wall of a microorganism and reacts with the microorganisms DNA (deoxyribonucleic acid). The C=C carbon bond in the molecules of the microorganism is broken causing cellular death. The microorganism is rendered incapable of growing and multiplying. UV is very effective, destroying 99.9% of harmful organisms.
After UV light exposure, a strong oxidative effect occurs on any orgaism that passes through the media, converting algae, pathogens, and viruses into harmless inert byproducts.
3. How is UV used in industry?
UV is commonly used in drinking water and wastewater treatment plants and is finding an increased usage in swimming pool treatment. Many bottlers of spring water use UV disinfection to sterilize their water. New York City has approved the construction of a 2 billion gallon per day ultraviolet water disinfection facility.
4. Why is UV especially well suited for swimming pool sterilization?
UV has two very impressive effects on swimming pool water. First, UV destroys 99.9% of harmful organisms as they pass through the SpectraLight sterilizer chamber. This germicidal benefits of UV has been known for decades. The scientific community recently discovered a second benefit which is equally impressive as the first. UV almost perfectly unlinks the hypochorous acid from ammonia, destroying unwanted combined chlorine, also known as chloramines. Chloramines are known to cause a host of problems in swimming pools, from the foul odor to burning eyes, and skin irriation. In addition, they have been linked to much more serious conditions such as "swimmers asthma" and bladder cancer.
5. Who advocates UV and who is using UV technology for swimming pools?
The U.S. Environmental Protection Agency recognizes UV as a proven technology:
"Ultraviolet (UV) radiation has been found to be an effective disinfectant….Simplicity of installation, ease of operation and maintenance, and low costs relative to chemical disinfection, make UV a useful small systems disinfection technology option." EPA, August 1997The World Health Organization recommended for swimming pool sanitization.
The State of New York requires UV sterilizers on all water parks.
The Olympic Games in Athens and Sydney utilized UV lights for their swimming pools.
The University of Texas and Yale University use UV to purify their swimming pools.
NASA has used UV for purification.
Visit our UV Pool Sterilizer Accolades page for more on where UV is used
6. Does a UV lamp us a lot of energy?
No, UV lights are highly efficient. Residential SpectraLIght sterilizers use about the same electricity as a low wattage light bulb. It's a very cost effective method of pool sterilization, often saving hundreds or even thousands in annual maintenance costs.
7. Why not just use chlorine in my swimming pool or spa?
When chlorine combines with perspiration, urine, oils and organic matter, harmful by-products called Trihalomethanes (THMs) are formed. These nasty by-products have been linked to cancer, asthma, and other diseases. Scientists are just beginning to discover how harmful these chemical compounds are to human health. For more information, visit our risks of chlorine page.
UV destroys nearly 100% of chlorine byproducts and chloramines. In addition, UV has been proven to deliver the lowest cost of ownership by lowering dependence on chlorine and chemicals.
8. What are the common problems in high chlorine pools that indicate a pool is not safe?
Pools that use traditional levels of chlorine can become sort of a chemical soup of chlorine by-products when chlorine combines with perspiration, oils, and organic debris. The unwanted chemicial compounds cause:
- the "pool smell" that people usually associate with chlorine
- red, burning eyes
- burning sesation in the nose, throat, and lungs
- dry, itchy skin, and dry hair
- breathing difficulty leading to "swimmers asthma", particularly in young children
- milky colored water
- green water due to high combined chlorine levels
9. Do I still need a residual sanitizer for my pool with SpectraLight installed?
SpectraLight does not recommend using UV technology as the sole method of pool or spa santization. UV does not enter the pool and no UV residual is maintained in the water. It is impossible to pass the internal parts of your pool (ie. wall, ladder, etc.) through the sterilizer. The good news is with UV, a little residual sanitizer goes a long way.
10. How much can I lower the use of chlorine in my pool?
SpectraLight UV has the ability to eliminate up to 80 - 90% of chlorine used in traditional chlorinated pools (commercial pools may require slightly higher residuals). A small residual level of Free Available Chlorine between .3 and .5 ppm is recommended. This is about the about the level found in drinking water. If you must eliminate all chlorine, see the #17 I'm Allergic to Chlorine question. Most experts agree that a low level of Free Available Chlorine is safe and does not pose a health risk. Chlorine side effects are eliminated at this low chlorine level.
11. Is my existing salt system (chlorine generator) compatible with SpectralLight?
Yes, because salt systems simply make chlorine, SpectraLight is compatible with salt systems and chlorine generators. SpectraLight will allow you to dial down the amount of chlorine the salt system manufactures.
However, there are pool owners who successfully use SpectraLight with no chlorine by choosing other residual sanitizers. Again, we recommend a low level of chlorine for safety and simplicity.
12. How do I maintain a low chlorine residual in my pool?
A .3 - .5 chlorine residual can be maintained using a few 1" or 3" chlorine tablets. Most pools do not require many tablets to reach a 1/2 ppm chlorine residual. Automatic feeders are thought to be the better choice as they release precise amounts of chlorine into your pool water. A floating chlorine feeder or an automatic chlorine feeder can be found at most supply stores.
13. Do I still need to test the pH and alkalinity?
Yes, but it becomes much easier. Maintaining proper pH is very important to maintaining neutral water that does not burn your eyes. High chlorine levels and high combined chlorine can cause a high variation in pH. A pool which has UV in use will tend to have a very stable pH and alkalinity, so adjustments will be rare.
14. How much is 1/2 ppm Free Available Chlorine (FAC)?
1/2 part per million (PPM) is a very, very low amount of chlorine. 1/2 PPM is equivalent to:
- one drop of dye in 36 gallons of water. - one second in 24 days- one penny out of $20,000.15. What Combined Available Chlorine (CAC) level do you recommend?
SpectraLight recommends a Combined Available Chlorine level of 0.
16. How can I obtain a Combined Available Chlorine level of 0 ppm, and a Free Available Chlorine (FAC) level of 1/2 ppm.
SpectraLight is designed to automatically and continuously lower CAC to 0 or near 0. SpectraLight destroys ammonia and the organic compounds that form CAC, or chloramines. A FAC level of 1/2 PPM may be maintained with a small amount of chlorine tablets, released with a floater or automatic feeder.
17. I'm allergic to chlorine. I want to eliminate all chlorine in my pool. Is that possible?
You may consider trying a low level of Bromine. Bromine is preferred by some pool and spa owners that are allergic to even very low levels of chlorine. Bromine is also available in tablet form and can be added to pool water using a chemical feeder to dissolve the tablets. The disadvantage to bromine is that it is more expensive than chlorine. SpectraLight recommends trying a low chlorine residual of .3 - .5 ppm for individuals that are sensitive to traditional chlorine levels. Please remember, .5 PPM is equivalent to one drop in 36 gallons of water, a very low level.
18. Do you have a dealer network for SpectraLight?
SpectraLight is a manufacturer that sells direct to pool owners. SpectraLight investigated establishing a dealer network and ultimately chose to go direct. SpectraLight sterilizers are easily shipped anywhere and can be installed in less than 30 minutes by the pool owner or any plumber. Installation does not require a "pool company". Pool owners appreciate the 30 - 50 in cost savings realized from our direct sales model.
Although we are not pursuing dealers, we occassionally sell to dealers, especially in foreign countries.
19. Is UV safe for swimming pools and spas?
Yes, the safety of UV for sterilizing swimming pools has been proven over decades. UV began purifying drinking water over 30 years ago. UV does not leave the sterilization chamber nor does it produce any residual in the water. SpectraLight should be used only as directed, and the unit should not be disassembled and turned on.
20. I've heard of some other way of eliminating chlorine in a pool. Does it work?
Over the years, there have been attempts to make and sell devices with the claim of replacing chlorine in swimming pools. Some of these devices can still be found online. The problem is that most are not based on sound scientific principles and simply do not work. UV is the most popular non-chlorine sanitizer at municipalities and major universities.
21. What three questions should I ask before choosing an alternative pool sanitation method?
1. Is the technology based on proven data widely accepted by the scientific community?2. Has the technology been recommended by leading health and environmental organizations? 3. Have municipalities and leading universities chosen the technology for their swimming pools?22. What is the warranty on the SpectraLight UV system?
All SpectraLight UV housings have a limited lifetime warranty against failure to defects in materials and/or workmanship. The complete unit is covered for one year from the date of purchase or 18 months from the date of manufacture.
23. How can I try SpectraLight with no risk or obligation?
SpectraLight’s try me option allows you to try out SpectraLight (residential units qualify) for up to 30 days in your own pool or backyard. If you’re not completely satisfied, simply return it to us and we’ll refund your investment, less shipping. Try SpectraLight for 30 days and chances are we couldn’t get it back if we tried!
24. How much is shipping and how is SpectraLight shipped?
Visit our shipping page for details.
25. Where do I install my SpectraLight UV sterilizer?
SpectraLight sterilizers are installed on the filteration pad, near your pump and filter. The best place to install your SpectraLight is after the filter. However, if installation after the filter is not feasible, it may be installed before the filter.
26. How long does it take my SpectraLight to sterilize/clarify/safeguard my pool or spa?
Your SpectraLight will begin working immediately. Since all of the water must pass through the sterilizer, it typically takes 1-2 days to see improvement. After 3-5 days, most owners report a level of clarity and color they have never seen before.
27. Do I install my SpectraLight vertically or horizontally?
For convenience and ease of installation, you can install a SpectraLight either way.
28. How long should I run my pool pump each day?
We recommend running the pump at least 12 hours per day. Experts agree that it is better and more cost efficient to operate a pool pump longer, 12 - 24 hours per day, but to operate it at a slower speed (RPM). Many states such as California have made 2-speed/multispeed pumps mandatory. These new style pumps have the ability to lower electrical consumption up to 80% and will pay for the upgrade costs many times over. The rule of thumb is a 50% reduction in pump speed uses 1/8 of the electricity.One option to consider is the Pentair Intelliflo.
29. How long should I run my SpectraLight each day?
We recommend running SpectraLight when your pump is operating, 12 - 24 hours per day. Please note that operating a pump slower, but longer can save 80% in electricity use. Consider upgrading to a 2-speed or multi-speed pump such as the Pentair Intelliflo if you don't already have one.
30. How often do I need to clean the unit or perform any maintenance?
The Quartz sleeve should be cleaned once every 1-2 weeks. The unit contains an ingenious quartz wiper which cleans the Quartz sleeve much like a squeegee cleans your windshield. To quickly and easily clean the unit, you simply move the black handle on each unit back and forth 3-4 times.
31. How often does the UV lamp for my swimming pool or spa need to be replaced?
The UV lamp must be replaced once a year. The ability to emit UV light decreases over time and replacement ensures your pool is protected well before the UV power significantly declines.
32. I love what SpectraLight does. How can I help?
We would greatly appreciate your help. Please recommend this site to family and friends by clicking
SpectraLight UV is an innovative water quality company focused on helping swimming pool and spa owners deploy advanced UV pool light technology to streamline swimming pool maintenance and minimize the use of dangerous chemicals. Serving all 50 states and shipping worldwide. Copyright © 2009 SpectraLight Ultraviolet, All Rights Reserved.
Have questions?
Need advice?
Call 1-888-895-7080
Have questions?
Need advice?
Call 1-888-895-7080
Frequently Asked Questions (FAQ)
General UV Questions
I Have SpectraLight, Now What do I do?
SpectraLight Pre-Purchase Questions
SpectraLight offers introductory answers to frequently asked questions about pool UV systems, installation, and maintenance. Click on a subject heading below to skip to a section to view questions and answers. Should you have any further questions, please consult our Contact Us page.
16. How can I maintain a Combined Available Chlorine level of 0 ppm, and a Free Available Chlorine (FAC) level of 1/2 ppm.
UV in General
Moving from a High Chlorine Pool World
Moving from a High Chlorine Pool World
I Have SpectraLight, Now What do I do?
SpectraLight Pre-Purchase Questions
