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NSF 55 Ultra Violet Disinfection

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IMPORTANT INFORMATION TO CONSIDER

check Systems have Minimum Operating Conditions
check Correct sizing is critical for Proper Disinfection
check Pre-Treatment of the water may be necessary
check 5 Micron filtration is required ahead of the UV
check Hardness, Iron and Sulphur can foul a System
check UV Transmittance must be greater than 75%
check Flow Restrictor is required with every System

Did You Know?
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Water Quality is Important for Proper

Operation of an NSF55 Ultra

Violet Light Disinfection System

 

 

Water Testing - Learn More >

Ontario Regulation 318/09 & 319/09 - Learn More >

NSF/ANSI 55 Ultraviolet Microbiological Water Treatment Systems

Point-of-entry and point-of-use systems covered by this Standard are designed to inactivate and/or remove microorganisms, including bacteria, viruses, Cryptosporidium oocysts and Giardia cysts from contaminated water. Systems covered by this Standard are not intended for the treatment of water that has an obvious contamination or intentional source, such as raw sewage, nor are systems intended to convert wastewater to drinking water. The systems are intended to be installed on visually clear water (not colored, cloudy, or turbid).

Water Quality Considerations
Parameter Contaminant Level
Hardness < 7 Grains Per Gallon (GPG)
Iron (Fe) < 0.3 Parts Per Million (PPM)
Turbidity < 1 NTU
UV-T > 75% UV Tranmittance
Manganese < 0.5 Parts Per Million (PPM)
Tannins < 0.1 Milligrams Per Litre ( mg/L)

 

The NSF 55 Class A Certification requires the system to deliver a 40 mJ/cm² UV dose at the certified flow rate at 70% UVT (Ultraviolet Transmittance). The certified flow rates are determined by NSF through testing protocols. Systems must provide a 4-log reduction (99.99%) of bacteria, virus and protozoan cysts (Giardia lamblia and Cryptosporidium). Class A systems shall be equipped with a UV Sensor to indicate when the UV irradiance at the sensor is below the minimum required by this Standard.

One or more of the following means shall be used to indicate ineffective operation:– a visual alarm;– an audible alarm; or– a system that terminates discharge of water. Water Quality is critical to ensuring proper disinfection and avoiding unecessary nuisanse alarms, boil water advisories and shutdowns. Testing of the water source is important before selecting a NSF 55 Ultra Violet System.

NSF 55 Class A Ultra Violet disinfection systems are widely used for public facilites such as campgrounds, marina's, trailer parks, restaurants and any other regulated facility serving water to the public that is not on a municipal water supply.