NSF ANSI 55-2019 pdf free download – Ultraviolet Microbiological Water Treatment Systems.
1 General1.1 Purpose
The purpose of this Standard is to establish minimum requirements for the reduction of microorganismsusing ultraviolet (UV) radiation. UV water treatment systems covered by this Standard are intended forwater that may be either microbiologically safe or microbiologically unsafe.This Standard also specifies theminimum product literature and labeling information that a manufacturer shall supply to authorizedrepresentatives and system owners, as well as the minimum service-related obligations that themanufacturer shall extend to system owners.
1.2Scope
This Standard covers UV microbiological water treatment systems and components for point-of-use (PoU)and point-of-entry(POE) applications.This Standard covers systems which use UV radiation within therange of 240 nm to 300 nm inclusive. Systems are intended to be used under the following specificconditions.
1.2.1 Class A systems
Class A POE and Pou systems covered by this Standard are designed to be used for treatingmicrobiologically unsafe water, but do not reduce chemical or inert particulate contaminants. Systemscovered in this Standard are designed to inactivate microorganisms，including bacteria，viruses,Cryptosporidium oocysts, and Giardiacysts, from water.Systems covered by this Standard are not intendedfor 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 installedon visually clear water (not colored, cloudy,or turbid).Systems with manufacturer claims that includecomponents or functions covered under other NSF or NSF/ANSl Standards or Criteria shall conform to theapplicable requirements therein.
Class Asystems not installed downstream of a device tested for cyst reduction / inactivation in conformanceto the appropriate NSF/ANSI Standard may claim Cryptosporidium oocysts and Giardia cysts only.Class A systems installed downstream of a device tested for cyst reduction in conformance toNSFIANSI 53 or NSF/ANSl 58 may make a general cyst claim when used on untreated surface waters, orground water, or both, under the direct influence of surface water.
NOTE – Current data support that Cryptosporidium oocysts and Giardia cysts are inactivated byuv treatment.
1.2.2Class B systems or components
Class B POE and PoU systems covered by this Standard are designed to be used for supplementalbactericidal treatment for the inactivation of microorganisms that may be present in drinking water(public or private) considered to be microbiologically sate and of known quality. Systems covered underthis Standard are intended to inactivate normally occurring nonpathogenic nuisance microorganisms only.
The Class B system is not intended for the disinfection of microbiologically unsafe water and may not makeindividual or general cyst claims. Class B systems shall not make microbiological health effects claims.Systems covered by this Standard (Class B) are not intended to be used with water that is microbiologicallyunsate or of unknown quality without adequate disinfection before or after the system. Systems withmanufacturer claims that include components or functions covered under other NSF or NSFIANSIStandards or Criteria shall conform to the applicable requirements therein.
1.3Variance from minimum requirements
Variations from the minimum requirements specified in Sections 4,5,6, and 7 may be permitted, providedthat they give the system or component the same or greater resistance to corrosion, wear, and physicaldamage, or that they improve the general operation or pertormance of the system or component. Proposedvariations shall be accepted by the testing agency prior to use. Systems with components or functionscovered under existing NSF Standards or criteria shall conform to the applicable requirements therein.1.4Alternate materials
lf specific materials are mentioned, other materials that provide at least equal performance and sanitationshall be acceptable.
2Normative references
The following documents contain provisions that, through reference, constitute provisions of this NSF/ANSIStandard.At the time this Standard was balloted, the editions listed below were valid.All documents aresubject to revision, and parties are encouraged to investigate the possibility of applying the recent editionsof the documents indicated below.The most recent published edition of the document shall be used forundated references.
21CFR Parts 170-199,Food and Drugs8
APHA,Standard Methods for the Examination of Water and Wastewater, twentieth edition9NSF/ANSI 53,Drinking Water Treatment Units – Health Effects
NSFIANSI 58, Reverse Osmosis Drinking Water Treatment SystemsNSFIANSICAN 61，Drinking Water System Components – Health EffectsNSFIANSI 62,Drinking Water Distillation SystemsNSF ANSI 55 pdf download.