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The Emperor Aquatics, Inc. Approach to Successful UV Sterilization
Successful ultraviolet disinfection demands strict adherence to Established Engineering Guidelines (The Bolton Photosciences, Inc. “Ultraviolet Applications Handbook” and the EPA). Emperor Aquatics, Inc. understands the importance of openly sharing critical UV performance information with the public. Our approach is simple. Education instills confidence in our equipment which leads to successful operation. Ultraviolet sterilization is unmatched in its efficiency, simplicity, and dependability when applied as a microorganism disinfectant but does have its limitations. Realizing both the benefits and limitations of UV disinfection establishes a foundation for its successful application.
Emperor Aquatics, Inc. Testimonials:
Here are a few unsolicited testimonials from satisfied Emperor Aquatics, Inc. customers.
Successful UV Disinfection
Our diverse clientele ranges from hobbyists to regulated facilities. At any given time Emperor Aquatics, Inc. is involved in specifying UV equipment for customer applications. Many customers require extremely detailed technical support. Here is one prime example of utilizing our technical expertise to achieve successful UV disinfection:
In 2002 the United States Fish & Wildlife Service issued authorization for a design/build project for the installation of a UV disinfection system to control disease at the Lahontan National Fish Hatchery Complex.This project was initiated to combat disease (Ich and Furunculosis) as well as to increase production. Emperor Aquatics, Inc. (working in conjunction with Water Management Technologies) was awarded the task of designing and manufacturing this UV equipment.
This project was unique because it involved the recovery of the threatened Lahontan cutthroat trout (Onchorynchus clarkihenshawi) and the endangered cui-ui (Chasmistes cujus). This project demanded critical attention to detail relative to accurate design, manufacturing and operating criteria. After installation of our UV equipment, there was an impressive fish production gain of +214%. Additionally, the hatchery was awarded “Disease Free Hatchery Status”. The result proved the value of UV design and flow rate accuracy. Today, successful UV disinfection continues at the Lahontan facility
The Objective: To Achieve Successful Germicidal Disinfection in a “Continuous-flow” Aquatic Life Support System
Achieving successful “germicidal disinfection” can only be accomplished by directly exposing the living target microorganism to the specific spectral area of UV-C for a predetermined amount of time (UV dose). Ultraviolet light consists of four specific spectral areas: Vacuum UV, UV-C, UV-B and UV-A (see the Light Spectrum Chart below). However, the established “Germicidal Action Spectrum” lies between 240-280 nm. The peak wavelength of 264 nm is the most lethal to a living organism’s DNA, and prevents it from reproducing.
Microoganisms' UV Doses for Ultraviolet Sterilization
In order to accomplish effective UV Sterilization we need to establish the targeted microorganism and its required UV Dose. Click the microorganism link to learn more about their role in successful UV Disinfection.
UV Water Flow Rates
The subject of “UV water flow rates” is highly controversial and for a good reason. Most of the information promoted by sub par competitors is NOT validated. This tainted information is widespread, and has virtually ruined the public’s perception of UV (with exception of those markets that are regulated). The sad fact is that the public, institutions, and even our government, are paying for bio-security that they never receive.
A UV Water Flow Rate must be a “validated” calculation that identifies the precise UV dose received from an individual UV sterilizer. All Emperor Aquatics, Inc. UV flow rates are calculated using the “Third-Party Validated” Bolton Photosciences, Inc. UV CALC Modeling Program, which is recognized by the United States Environmental Protection Agency (USEPA).
The Bolton Photosciences Inc. UV CALC Modeling Program calculates a specific UV sterilizer’s achieved UV dose based upon:
- The unit’s UV-C Output Performance Capacity
- The application’s %UVT (Percent UV Transmissibility of the water)
- The operating water flow rate.
Perhaps the most overlooked, yet most critical UV performance factor when assessing an application’s UV requirement/demand, is the water’s “UV Transmittance” which is expressed in percent (0-100%). %UVT is the measured value between a known UV light source (@ 254 nm) and what is measured by a calibrated detector through a 1 cm thick sample of the water to be treated.
The measured value (%UVT) is expressed as the total amount of UV light energy available to treat the water. The higher the % value the greater the UV dose will be. UV light that is absorbed by substances in the water is unavailable to inactivate microorganisms. When more UV light is absorbed (i.e. low %UVT), greater UV capacity will be required to compensate for the loss due to absorption. Specifying UV equipment properly can not legitimately take place without first identifying the %UVT.
The following charts demonstrate how a lower %UVT parallels a diminished UV dose when operating our model CLP6780-A8 (3-260 Watt Amalgam UV Lamps) at a flow rate of 150 GPM. Notice the distinct drop in UV dose when considering a slightly lower %UVT.
Other Ultraviolet Sterilizer Factors to consider:
Ultraviolet Sterilization's Benefits and Limitations
UV Benefits:UV treatment takes place only inside the UV exposure chamber and leaves no residual downstream. Therefore, it is harmless to the animals in the pool. UV sterilization is a proven solution to harmful waterborne pathogens commonly associated with aquatic recirculating systems. In contrast, chlorine/bromine leaves a residual in the water that can irritate the skin and eye tissue of mammals, reptiles, and birds. Ozone, if not measured and controlled properly, is capable of causing severe tissue damage, even death in fish and invertebrates.
UV Limitations:Exposure time between the waterborne microorganism and the UV-C light is critical to achieving successful UV disinfection. The condition of the application’s water (%UVT) will determine how well the UV-C light penetrates through it. UV-C is absorbed by the targeted microorganism or by other organic waterborne particles. It is for this reason that UV equipment should be positioned after the mechanical filter.
Only Emperor Aquatics, Inc. provides you, the customer, with the necessary information to make an informed purchasing decision.
How to select the proper UV Sterilizer equipment:
Start with selecting your “target microorganism” and use its established UV dose as a benchmark. Next, using only validated UV equipment performance specifications, select the UV model that matches the conditions of your application (required UV dose, %UVT & Flow rate). NOTE: Only Emperor Aquatics, Inc. provides a UV dose calculation spread sheet (upon request) for the model you are interested in purchasing. Beware of competitors that are unwilling, or can not supply this spreadsheet!
If you still have questions regarding Ultraviolet Sterilization or how to select the right UV Sterilizer for your application please feel free to send us an e-mail here: UV Sterilization Questions.