Incorporating Amendment No. 1 New Zealand Standard Underground fire hydrants Superseding NZS/BS 750:1984
COMMITTEE REPRESENTATION This standard was prepared under the supervision of the P 4522 Committee the Standards Council established under the Standards Act 1988. The committee consisted of representatives of the following nominating organisations: Casting Technology New Zealand Inc. Ingenium Local Government New Zealand New Zealand Fire Equipment Manufacturers Association Inc. New Zealand Fire Service New Zealand Transport Agency Water Industry Operations Group Water New Zealand ACKNOWLEDGEMENT Standards New Zealand gratefully acknowledges the contribution of time and expertise from all those involved in developing this standard. Standards New Zealand would like to thank the British Standards Institute for use of figure 2, which is based on figure 3 from BS 750:2006. COPYRIGHT The copyright of this document is the property of the Standards Council. No part of this document may be reproduced by photocopying or by any other means without the prior written permission of the Chief Executive of Standards New Zealand, unless the circumstances are covered by Part 3 of the Copyright Act 1994. Standards New Zealand will vigorously defend the copyright in this standard. Every person who breaches Standards New Zealand s copyright may be liable, under section 131(5) (a) of the Copyright Act 1994, to a fine not exceeding $10,000 for every infringing copy to which the offence relates, but not exceeding $150,000 for the same transaction, or to imprisonment for a term not exceeding 5 years. Those in breach under section 131(5) (b) of the Copyright Act 1994 may be liable to a fine not exceeding $150,000 or to imprisonment for a term not exceeding 5 years. If there has been a flagrant breach of copyright, Standards New Zealand may also seek additional damages from the infringing party, in addition to obtaining injunctive relief and an account of profits. Published by Standards New Zealand, the trading arm of the Standards Council, Private Bag 2439, Wellington 6140. Telephone: (04) 498 5990; Fax: (04) 498 5994; Website: www.standards.co.nz. AMENDMENTS No. Date of issue Description Entered by, and date 1 12/02/2014 Update the hydrant loss pressure in 7.3.3 to 100 kpa Incorporated in this edition.
Incorporating Amendment No. 1 New Zealand Standard Underground fire hydrants Superseding NZS/BS 750:1984 ISBN (Print) 978-1-77551-235-6 ISBN (PDF) 978-1-77551-236-3
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CONTENTS Committee representation... IFC Acknowledgement... IFC Copyright... IFC Referenced documents...5 Related documents...7 Latest revisions...7 Review of Standards...7 Foreword...8 Outcome statement...9 Section 1 GENERAL... 11 1.1 Scope... 11 1.2 Objective... 11 1.3 Interpretation... 11 1.4 Definitions and abbreviations...12 2 CLASSIFICATION OF HYDRANT...15 2.1 Screw-down hydrant...15 2.2 Gate valve hydrant...15 3 INSTALLATION OF FIRE HYDRANTS...16 3.1 General...16 3.2 Clearances...16 3.3 Clear opening...16 3.4 Surface box...16 3.5 Concrete hydrant riser blocks...16 4 MATERIALS AND COMPONENTS...19 4.1 Materials...19 4.2 Hydrant components in contact with potable water...21 4.3 Dezincification-resistant materials...21 5 HYDRANT DESIGN...22 5.1 General...22 5.2 Allowable operating pressure...22 5.3 Required flow...22 5.4 Dimensions...23 5.5 Component jointing...23 5.6 Spindle design...26 5.7 Threaded outlet design...27 5.8 Stopper design...28 5.9 Design of screw-down hydrant body...29 5.10 Requirements for auto-drain plug...29 3
6 COATINGS...30 6.1 General...30 6.2 Colour of external coating...30 7 TESTING...31 7.1 Type tests...31 7.2 Strength, pressure, seating, and functionality type tests...31 7.3 Hydrant flow type testing...35 7.4 Cyclical endurance type testing...36 7.5 Production testing...37 7.6 Demonstrating compliance with the Standard...37 8 MARKING AND PACKAGING...38 8.1 Marking of screw-down hydrants...38 8.2 Packaging...38 Appendix A Typical arrangement for hydrants (Normative)...39 B Flow testing of hydrants (Normative...41 C Means for demonstrating compliance with this Standard screw-down hydrants only (Normative)...42 Table 1 Allowable dimensions for figure 1...18 2 Basic materials for manufacture of screw-down fire hydrants...19 3 Basic components and materials for manufacture of components of gate valve fire hydrants...20 4 Allowable pressures...22 5 Minimum strength requirements for testing screw-down hydrants...32 C1 Minimum sampling and type testing frequency Hydrants...43 C2 Minimum sampling and production testing frequency Hydrants...45 Figure 1 Installation clearances for screw-down fire hydrants...17 2 Threaded outlet and dust cap...24 3 Dimension of mounting flange on screw-down hydrant...25 4 Dimension of hydrant spindle cap...27 5 Arrangement for supporting stopper when testing strength of guides...33 6 Suggested arrangement for strength testing of threaded outlet...34 A1 Typical arrangement of the screw-down fire hydrant Non-rising spindle type...39 A2 Typical arrangement of the screw-down fire hydrant External spindle nut type...39 A3 Typical arrangement of the gate valve fire hydrant...40 B1 Test rig for flow testing hydrants...41 4
REFERENCED DOCUMENTS Reference is made in this document to the following: NEW ZEALAND STANDARDS AND SPECIFICATIONS NZS/BS 750:1987 NZS/BS 1387:1985 SNZ PAS 4509:2008 Specification for underground fire hydrants and surface box frames and covers Specification for screwed and socketed steel tubes and tubulars and for plain end steel tubes suitable for welding or for screwing to BS 21 pipe threads New Zealand Fire Service firefighting water supplies code of practice JOINT AUSTRALIAN/NEW ZEALAND STANDARDS AS/NZS 2280:2004 AS/NZS 4020:2005 AS/NZS 4131:2010 AS/NZS 4158:2003 Ductile iron pipes and fittings Testing of products for use in contact with drinking water Polyethylene (PE) compounds for pressure pipes and fittings Thermal-bonded polymeric coatings on valves and fittings for water industry purposes JOINT AUSTRALIAN/NEW ZEALAND HANDBOOKS SNZ/SAA HB 18.28: 1991 Guidelines for third-party certification and accreditation Guide 28 General rules for a model third-party certification system for products INTERNATIONAL STANDARDS ISO 4288:1996 Geometrical product specifications (GPS) Surface texture: Profile method Rules and procedures for the assessment of surface texture AUSTRALIAN STANDARDS AS 1111: - - - - Part 1:2000 Part 2:2000 AS 1565:1996 AS 1646:2007 AS 1683: - - - - Part 15.1:2000 AS 1830:2007 AS 1831:2007 AS 2129:2000 AS 2345:2006 AS 2638: - - - - Part 2:2006 ISO metric hexagon bolts and screws Product grade C Bolts Screws Copper and copper alloys Ingots and castings Elastomeric seals for waterworks purposes Methods of test for elastomers International rubber hardness Grey cast iron Ductile cast iron Flanges for pipes, valves and fittings Dezincification resistance of copper alloys Gate valves for waterworks purposes Resilient seated 5
AS 3894: - - - - Part 1:2002 AS 3996:2006 AS 4087:2004 Site testing of protective coatings Non-conductive coatings Continuity testing High voltage ( brush ) method Access covers and grates Metallic flanges for waterworks purposes BRITISH STANDARDS BS 10:2009 BS 336:1989 BS 750:2006 Specification for flanges and bolting for pipes, valves and fittings Specification for fire hose couplings and ancillary equipment Specification for underground fire hydrants and surface box frames and covers NOTE BS 10:2009 is largely a reprint of BS 10:1962 and remains in imperial units. Key dimensions of flanges are unchanged from BS 10:1962. AMERICAN STANDARDS ASTM A276-08a Standard specification for stainless steel bars and shapes ASTM A743/A743M-06 Standard specification for castings, iron-chromium, ironchromium-nickel, corrosion resistant, for general application ASTM D429-08 Standard test methods for rubber property Adhesion to rigid substrates OTHER PUBLICATION New Zealand Transport Authority NZTA Manual of traffic signs and markings, 2010 NEW ZEALAND LEGISLATION Utilities Access Act 2010 WEBSITES http://www.jas-anz.com.au http://www.legislation.govt.nz 6
RELATED DOCUMENTS Although not referenced in this Standard the following documents also contain helpful information: JOINT NEW ZEALAND/AUSTRALIAN STANDARD AS/NZS 1594:2002 Hot-rolled steel flat products AUSTRALIAN STANDARDS AS 1442:2007 AS 1567:1997 Carbon steels and carbon manganese steels Hot-rolled bars and semifinished products Copper and copper alloys Wrought rods, bars and sections BRITISH STANDARDS BS 2872:1989 BS EN 12163:1998 BS EN 12164:1998 BS EN 12167:1998 Specification for copper and copper alloy forging stock and forgings Copper and copper alloys. Rod for general purposes Copper and copper alloys. Rod for free machining purposes Copper and copper alloys. Profiles and rectangular bar for general purposes OTHER PUBLICATION New Zealand Utilities Advisory Group (NZUAG) The national code of practice for utilities access to the transport corridors, implementation version, 2009 LATEST REVISIONS The users of this Standard should ensure that their copies of the above-mentioned New Zealand Standards, joint Australian/New Zealand Standards and Handbooks, and New Zealand Publicly Available Specifications are the latest revisions. Amendments to referenced New Zealand and Joint Australian/New Zealand Standards can be found on http://www.standards.co.nz. REVIEW OF STANDARDS Suggestions for improvement of this Standard will be welcomed. They should be sent to the Chief Executive, Standards New Zealand, Private Bag 2439, Wellington 6140. 7
FOREWORD NZS 4522 specifies requirements for underground fire hydrants that are to be used in New Zealand. Changes from the requirements of NZS/BS 750 (the Standard previously used) reflect recent changes to hydrant manufacturing practices and technologies. Instead of developing this new New Zealand Standard, the P 4522 committee also considered adopting a number of international Standards (including BS 750). The committee made the decision to develop NZS 4522 a document ideal for New Zealand use, specifically designed for New Zealand conditions, and that cross references other local and regional Standards currently in use. This Standard defines two types of hydrant: (a) (b) Screw-down hydrant: This is a purpose designed, single-piece valve incorporating a threaded hydrant outlet. It is suitable for installation as a standard hydrant and is typical of fire hydrants normally installed by water supply authorities throughout New Zealand. Gate valve hydrant: This is an assembly comprising a resilient seated gate valve, suitable fittings, and a cast threaded hydrant outlet. Gate valve hydrants are intended to provide equivalent flows with less head loss across the assembly than would occur across a screw-down hydrant. Such hydrants shall only be designed by a competent person. Gate valve hydrants are suitable for installation on a purposedesigned flanged fitting and are intended to be installed only at locations where insufficient water main capacity prevents a screw-down hydrant from delivering required flows, or a screw-down hydrant cannot be installed because of physical limitations. The primary function of fire hydrants is to provide an adequate firefighting water supply to the New Zealand Fire Service (NZFS). Adequate firefighting water supplies, for each risk classification, are specified in SNZ PAS 4509. The hydrant performance criteria specified in NZS 4522 allow for the delivery of such flows through a screw-down hydrant with a standard hydrant standpipe fitted, and where the water reticulation system is operating at acceptable minimum pressures and flows. In addition to the hydrant s primary function, it is recognised that a hydrant shall also be capable of performing the following functions on a regular basis, as required by the NZFS or by the water supply authority: (c) (d) (e) (f) (g) (h) (i) (j) Controlled flow tests to establish the acceptability of the firefighting water supply; Controlled flow tests to establish the capacity of the water supply network; Removal of air from the high points in water mains; Emptying of water at low points before repairing the water mains; Flushing of sediment from water mains; Supplying water to mobile water treatment units (typically in water main contamination scenarios); Injecting super-chlorinated water into water mains (typically in water main contamination scenarios); Providing temporary hydrant-to-hydrant links where normal water supply to a water zone may be damaged or shut down; 8
(k) (l) Installing water pressure monitoring devices on the threaded hydrant outlet to record the running pressures in the water main; and Permitted supply of water via metered standpipe to contractors for delivery to third parties or for use in road construction. While fire hydrants are commonly used for scouring water mains, it should be noted that this practice may increase the risk of the hydrant sealing surfaces being damaged. The pressure ratings for the hydrant body and the strength criteria for the threaded outlet set out in this Standard provide for the functionality required from a screw-down or gate valve hydrant. OUTCOME STATEMENT The aim of is to outline the design, material, manufacture, and installation requirements for underground fire hydrants used in New Zealand. The end user of the Standard will benefit from being up to date with current technology and consistent practices. NZS 4522 will also benefit the community by facilitating efficient water supply management and continued access for the NZFS to underground fire hydrants during fire emergencies. 9
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New Zealand Standard Underground fire hydrants 1 GENERAL 1.1 Scope 1.1.1 Inclusions This Standard specifies the dimensional, material, installation, and performance requirements for screw-down and gate valve underground fire hydrants used in New Zealand. Screw-down hydrants shall be: (a) In size DN 80; (b) (c) Suitable for an allowable operating pressure (AOP) of 1.6 MPa/1,600 kpa (16 bar); and Fitted with one threaded outlet. Gate valve hydrants shall be purpose designed to suit the duty they are required to perform. 1.1.2 Exclusions This Standard excludes the specifications for road hydrant markings and operation of fire hydrants. NOTE Information on road hydrant markings is given in the NZTA Manual of traffic signs and markings. 1.2 Objective The objective of NZS 4522 is to promote the manufacture, supply, and use of fire hydrants with consistent high performance, long life, and low maintenance requirements, and to provide guidance on their installation. 1.3 Interpretation For the purposes of this Standard, the word shall refers to requirements that are essential for compliance with the Standard, while the word should refers to practices that are advised or recommended. The term Normative has been used in this Standard to define the application of the Appendix to which it applies. A Normative Appendix is an integral part of the Standard and contains requirements. 11
Underground fire hydrants This is a free sample only. Purchase the full publication here: https://shop.standards.govt.nz//catalog/4522%3a2010%28nzs%29/view Or contact Standards New Zealand using one of the following methods. Freephone: 0800 782 632 (New Zealand) Phone: +64 3 943 4259 Email: enquiries@standards.govt.nz