1、NSF International Standard / American National StandardNSF/ANSI 55 - 2017 Ultraviolet MicrobiologicalWater Treatment Systems NSF International, an independent, not-for-profit, non-governmental organization, is dedicated to being the leading global provider of public health and safety-based risk mana
2、gement solutions while serving the interests of all stakeholders. This Standard is subject to revision. Contact NSF to confirm this revision is current. Users of this Standard may request clarifications and interpretations, or propose revisions by contacting: Chair, Joint Committee on Drinking Water
3、 Treatment Units c/o NSF International 789 North Dixboro Road, P. O. Box 130140 Ann Arbor, Michigan 48113-0140 USA Phone: (734) 769-8010 Telex: 753215 NSF INTL FAX: (734) 769-0109 E-mail: infonsf.org Web: http:/www.nsf.orgi NSF/ANSI 55 2017 NSF International Standard/ American National Standard for
4、Drinking Water Treatment Units Ultraviolet microbiological water treatment systems Standard Developer NSF International Designated as an ANSI Standard June 13, 2017 American National Standards Instituteii Prepared by The NSF Joint Committee on Drinking Water Treatment Units Recommended for Adoption
5、by The NSF Council of Public Health Consultants Adopted by The NSF Board of Directors May 1991 Revised January 2000 Revised August 2012 Revised January 2002 Revised December 2013 Addendum, June 2002 Revised January 2015 Addendum, February 2004 Revised December 2016 Revised October 2004 Revised Novem
6、ber 2017 Revised October 2007 Revised August 2009 Published by NSF International PO Box 130140, Ann Arbor, Michigan 48113-0140, USA For ordering copies or for making inquiries with regard to this Standard, please reference the designation “NSF/ANSI 55 2017.” Copyright 2017 NSF International Previous
7、 editions 2017, 2015, 2014, 2013, 2012, 2009, 2007, 2004, 2002, 2000, 1991 Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from NSF Interna
8、tional. Printed in the United States of America.iii Disclaimers1NSF International (NSF), in performing its functions in accordance with its objectives, does not assume or undertake to discharge any responsibility of the manufacturer or any other party. The opinions and findings of NSF represent its
9、professional judgment. NSF shall not be responsible to anyone for the use of or reliance upon this Standard by anyone. NSF shall not incur any obligation or liability for damages, including consequential damages, arising out of or in connection with the use, interpretation of, or reliance upon this
10、Standard. NSF Standards provide basic criteria to promote sanitation and protection of the public health. Provisions for mechanical and electrical safety have not been included in this Standard because governmental agencies or other national standards-setting organizations provide safety requirement
11、s. Participation in NSFs Standards development activities by regulatory agency representatives (federal, local, state) shall not constitute their agencys endorsement of NSF or any of its Standards. Preference is given to the use of performance criteria measurable by examination or testing in NSF Sta
12、ndards development when such performance criteria may reasonably be used in lieu of design, materials, or construction criteria. The illustrations, if provided, are intended to assist in understanding their adjacent standard requirements. However, the illustrations may not include all requirements f
13、or a specific product or unit, nor do they show the only method of fabricating such arrangements. Such partial drawings shall not be used to justify improper or incomplete design and construction. Unless otherwise referenced, the annexes are not considered an integral part of NSF Standards. The anne
14、xes are provided as general guidelines to the manufacturer regulatory agency, user, or certifying organization. 1The information contained in this Disclaimer is not part of this American National Standard (ANS) and has not been processed in accordance with ANSIs requirements for an ANS. Therefore, t
15、his Disclaimer may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements necessary for conformance to the Standard. This page is intentionally left blank.v Contents 1 General . 1 1.1 Purpose 1 1.2 Scope . 1 1.3 Variance fr
16、om minimum requirements . 2 1.4 Alternate materials . 2 2 Normative references . 2 3 Definitions . 3 4 Materials . 3 4.1 Materials in contact with drinking water . 3 4.2 Materials evaluation . 4 4.3 Gas chromatography/mass spectroscopy (GC/MS) analysis 5 5 Structural performance . 11 5.1 Structural
17、integrity 11 6 Minimum performance requirements 16 6.1 General. 16 6.2 Performance indication 17 6.3 Elements 18 6.4 Flow control 18 6.5 Waste connections . 18 6.6 Product water dispensing outlets . 18 6.7 Hazards 18 6.8 Lamp operation indication 18 6.9 Lamp replacement . 19 6.10 Maintenance 19 6.11
18、 Temperature resistance . 19 6.12 Corrodible materials 19 6.13 Gaskets, o-rings, shaft seals, and packing materials 19 6.14 Dissimilar metals . 19 6.15 Insulating fittings 19 6.16 Plastics 19 6.17 Welding 19 7 Elective performance claims test methods 20 7.1 General. 20 7.2 Microbiological performanc
19、e 20 8 Instructions and information . 29 8.1 Installation, operation, and maintenance instructions 29 8.2 Data plate . 31 8.3 Replacement components . 32 8.4 Performance data sheet . 32 Annex A Ultraviolet water treatment systems microbial reduction 35 Annex B Key elements of a certification program
20、 for drinking water treatment systems and components 43 Annex C. 47 This page is intentionally left blank.vii Foreword2The purpose of this Standard is to establish minimum requirements for the reduction of microorganisms using ultraviolet radiation (UV). UV water treatment systems covered by this St
21、andard are intended for water that may be either microbiologically safe or microbiologically unsafe. This Standard also specifies the minimum product literature and labeling information that a manufacturer shall supply to authorized representatives and system owners, as well as the minimum service-r
22、elated obligations that the manufacturer shall extend to system owners. Systems covered by this Standard are in keeping with the Report of Task Force on Guide Standard and Protocol for Testing Microbiological Water Purifiers, April, 1987.3It is recognized that the federal, state and local objectives
23、 are to provide safe water supplies without user treatment. However, many users are faced with the presence of contaminants of both aesthetic and health concern in their water supplies, and need guidance as to the availability of tested and certified point-of-entry and point-of-use ultraviolet water
24、 treatment systems. This Standard will help to meet this need but cannot be expected to address claims beyond those covered in this Standard. Since it was not economically feasible to mount a routine testing program using all of the target microorganisms, e. g., bacteria, viruses, and protozoan cyst
25、s, an equivalent “disinfection“ set of tests and requirements was developed for point-of-use and point-of-entry ultraviolet disinfection systems. A virus reduction of 4 log against a poliovirus and rotavirus challenge and a bacteriological reduction of 6 logs against a challenge of a coliform bacter
26、ia (Klebsiella terrigena) has been recommended by Schaub and an expert task force (1987).3The technical and health protection problems (laboratory staff) and the inherent cost of establishing and maintaining a live virus test program preclude its routine application in a multipurpose standards testi
27、ng laboratory. Consequently, an alternate means of assuring virus efficacy was developed. Survival data for poliovirus and rotavirus (Chang, 1985)4show that between a 3- and 4-log reduction in both poliovirus and rotavirus may be accomplished by a UV dosage of 30,000 W-sec/cm2while a greater than 6-
28、log reduction of Escherichia coli may be projected. Additional data (Harris, 1986)5show a 5-log reduction of poliovirus at 40,000 w-sec/cm2. In NSF/ANSI 55 2000, a minimum UV dosage of 38,000 W-sec/cm2at the failsafe setpoint was set as an equivalent 4-log virus reduction requirement. To be consiste
29、nt with International Standards, the minimum UV dose in NSF/ANSI 55 2002 was changed to 40 mJ/cm2 (40,000 w-sec/cm2) at the alarm set point. Prior to the late 1990s, it was thought that ultraviolet light had limited cysticidal ability, which required information for the user as to the need for a pre
30、filter complying with NSF/ANSI 53: Drinking water treatment units Health effects for cyst reduction. Survival data for Cryptosporidium (Clancy, 2000)6and Giardia (Craik, 2000)7show that a minimum 3- to 4-log reduction in both Cryptosporidium and Giardia may be 2The information contained in this Fore
31、word is not part of this American National Standard (ANS) and has not been processed in accordance with ANSIs requirements for an ANS. Therefore, this Foreword may contain material that has not been subjected to public review or a consensus process. In addition, it does not contain requirements nece
32、ssary for conformance to the Standard. 3Guide Standard and Protocol for Testing Microbiological Water Purifiers, Report of Task Force, submitted by Steven A. Schaub to the USEPA, April 1987 4“UV Inactivation of Pathogenic and Indicator Microorganisms,” Chang, J.C., Johnson, J. Doald, et al. Journal
33、of Applied Environmental Microbiology, Vol. 49, pp. 13611365, 1985 5“UV Inactivation of Selected Bacteria and Viruses With Photoreactivation of the Bacteria,” Harris, D. George, Adams, Dean, et al., Water Resources, Vol. 21, pp. 687692, 1986 6“Using UV to Inactivate Crypospordium,” Clancy, J. L., et
34、 al. Journal of American Water Works, Vol 92, Issue 9, pp. 97-104, 2000 7“Inactivation of Giardia Muris Cysts Using Medium-Pressure Ultraviolet Radiation in Filtered Drinking water,” Craik, viii accomplished by a UV dosage of 10 mJ/cm2. Where drinking water is considered to be free of disease causin
35、g pathogenic organisms and has a turbidity level within acceptable drinking water standards, ultraviolet treatment may be useful for the supplemental treatment of this drinking water. It would be suitable for the reduction of normally occurring microbiological flora (non-spore forming heterotrophic
36、bacteria) commonly found in drinking water. Survival data (Chang, 1985)4show that a greater than 2-log reduction of non-spore forming heterotrophic bacteria may be accomplished by an ultraviolet dosage of 16,000 W-sec/cm2. The yeast organism Saccharomyces cerevisiae was chosen as the test challenge
37、to allow for a reasonable influent concentration and an easily measured reduction in the effluent. Most vegetative bacteria, including coliform species, are too susceptible to UV radiation at the dose range of 16,000 W-sec/cm2to allow for measurable testing. This version of the Standard contains the
38、 following revisions: Issue 43 Normative references were updated. Issue 44 Evaluation criteria columns from tables 4.1, 4.2, and 4.3 were removed and now reference the evaluation criteria in Annex D, Table D.1 in NSF/ANSI 61. It is the intent of the Joint Committee to eliminate the use of S. cerevis
39、iae as a challenge organism for Class B devices from the Standard after September 2017, a period of five years from the adoption of using T1 Coliphage as a challenge organism for Class B devices. This Standard was developed by the NSF Joint Committee on Drinking Water Treatment Units using the conse
40、nsus process described by the American National Standards Institute. Suggestions for improvement of this Standard are welcome. This Standard is maintained on a Continuous Maintenance schedule and can be opened for comment at any time. Comments should be sent to Chair, Joint Committee on Drinking Wat
41、er Treatment Units at standardsnsf.org or, c/o NSF International, Standards Department, P.O. Box 130140, Ann Arbor, Michigan 48113-0140, USA. S. A., et al. Water Resources, Vol. 34, No. 18, pp 4325-4332, 2000 1 2017 NSF NSF/ANSI 55 2017 NSF/ANSI Standard for Drinking Water Treatment Units Ultraviole
42、t microbiological water treatment units 1 General 1.1 Purpose The purpose of this Standard is to establish minimum requirements for the reduction of microorganisms using ultraviolet radiation (UV). UV water treatment systems covered by this Standard are intended for water that may be either microbio
43、logically safe or microbiologically unsafe. This Standard also specifies the minimum product literature and labeling information that a manufacturer shall supply to authorized representatives and system owners, as well as the minimum service-related obligations that the manufacturer shall extend to
44、system owners. 1.2 Scope This Standard covers ultraviolet microbiological water treatment systems and components for point-of-use and point-of-entry applications. Systems are intended to be used under the following specific conditions. 1.2.1 Class A systems Class A point-of-entry and point-of-use sy
45、stems 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
46、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). Class A systems not installed downstream of a device tested for cyst reduction/inactivation in
47、conformance to 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/inactivation in conformance to the appropriate NSF/ANSI standard may make a general cyst claim when used on untreated
48、surface waters and/or ground water under the direct influence of surface water. NOTE Current data support that Cryptosporidium oocysts and Giardia cysts are inactivated by ultraviolet treatment. 1.2.2 Class B systems or components Class B point-of-entry and point-of-use systems covered by this Stand
49、ard are designed for supplemental bactericidal treatment of disinfected public drinking water or other drinking water that has been tested and deemed acceptable for human consumption by the state or local health agency having jurisdiction. The system is designed to reduce normally occurring nonpathogenic nuisance microorganisms only. The Class B system is not intended for the disinfection of microbiologically unsafe water and may not make individual or general cyst claims. Class B systems shall not make microbiological health effects claims. 2017 NSF NSF/A
