ISO 6182-6:2020

Fire protection - Automatic sprinkler systems - Part 6: Requirements and test methods for check valves

This document specifies performance, requirements, test methods and marking requirements, for check valves used to supply water in automatic fire protection systems. It is not applicable to trim valves.

Protection contre l'incendie — Systèmes d'extinction automatiques du type sprinkler — Partie 6: Exigences et méthodes d'essai des postes de contrôle

General Information

• Status: Published
• Publication Date: 26-Mar-2020
• ICS: 13.220.20 - Fire protection
• Technical Committee: ISO/TC 21/SC 5 - Fixed firefighting systems using water
• Drafting Committee: ISO/TC 21/SC 5/WG 10 - Valves
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 07-Jul-2025
• Completion Date: 13-Dec-2025

Relations

• Consolidated By: ISO 75-1:2020 - Plastics - Determination of temperature of deflection under load - Part 1: General test method
• Effective Date: 06-Jun-2022
• Revised: ISO 6182-2:2025 - Fire protection - Automatic sprinkler systems - Part 2: Requirements and test methods for sprinkler system alarm valves, check valves, water motor alarms, retard devices and accelerators
• Effective Date: 16-Sep-2023
• Revises: ISO 6182-6:2006 - Fire protection - Automatic sprinkler systems - Part 6: Requirements and test methods for check valves
• Effective Date: 04-Nov-2015

Overview - ISO 6182-6:2020 (check valves for automatic sprinkler systems)

ISO 6182-6:2020 is the international standard that specifies performance, requirements, test methods and marking for check valves used to supply water in automatic fire protection sprinkler systems. It applies to check valves (not trim valves) installed in the main waterway of sprinkler installations to prevent backflow and to help manage multiple pumps or flow-switch arrangements. Key takeaways: minimum nominal size DN25, rated working pressure ≥ 1.2 MPa (12 bar), and comprehensive mechanical, hydraulic and ageing tests.

Key topics and technical requirements

• Scope and applicability
  • Check valves for automatic sprinkler systems; not applicable to trim valves.
• Nominal sizes & connections
  • Valve sizes ≥ DN25; connections must meet the rated working pressure and relevant international/national standards.
• Rated working pressure
  • Minimum specified: 1.2 MPa (12 bar); manufacturer must specify rated working pressure.
• Materials and construction
  • Bodies and covers: materials with corrosion resistance at least equivalent to cast iron.
  • Cover fasteners: steel, stainless steel, titanium or equivalent.
  • Non-metallic body parts restricted; melting point of metals < 800 °C not permitted.
• Mechanical strength
  • Assembled valve (sealing assembly blocked open) must withstand 4× rated working pressure for 5 minutes without rupture.
• Hydraulics and clearances
  • Clearances, sealing assembly geometry and hydraulic friction loss are specified and tested.
• Operational durability and ageing
  • Endurance tests, spring tests, warm-water and air ageing for non-metallic components; salt mist corrosion assessment.
• Leakage and sealing
  • Defined leakage limits and deformation tests; sealing assembly must resist wear and allow maintenance.
• Testing, production control and marking
  • Production testing, sample tests (spring, body strength, leakage, endurance, friction loss) and marking/installation instructions required.

Practical applications - who uses this standard

• Manufacturers of check valves for sprinkler systems - for design, material selection, testing and marking.
• Test laboratories and quality-control teams - to perform required hydraulic, mechanical and ageing tests.
• Fire protection engineers and system designers - to specify compliant check valves and confirm rated working pressures, friction loss and maintenance access.
• Installers and maintenance personnel - for correct installation, serviceability and interpretation of manufacturer instructions.
• Authorities having jurisdiction and procurement teams - to assess product conformity for building fire-safety systems.

Related standards

• ISO 6182 series (other parts for automatic sprinkler systems)
• Normative references cited in ISO 6182-6: ISO 898-1 and ISO 898-2 (mechanical properties of fasteners)

This standard is essential when selecting, testing or certifying check valves for automatic sprinkler systems, ensuring reliable backflow prevention, hydraulic performance and long-term durability in fire protection applications.

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 6182-6
Second edition
2020-03
Fire protection — Automatic sprinkler
systems —
Part 6:
Requirements and test methods for
check valves
Protection contre l'incendie — Systèmes d'extinction automatiques du
type sprinkler —
Partie 6: Exigences et méthodes d'essai des postes de contrôle
Reference number
©
ISO 2020
© ISO 2020
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
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CH-1214 Vernier, Geneva
Phone: [phone]
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Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2020 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 2
4.1 Nominal sizes . 2
4.2 Connections . 2
4.3 Rated working pressure . 2
4.4 Bodies and covers . 2
4.5 Strength (see 6.3) . 3
4.6 Access for maintenance . 3
4.7 Components . 3
4.8 Leakage (see 6.4) . 4
4.9 Non-metallic components (excluding gaskets, seals and other elastomeric parts)
(see 6.5 and 6.6) . 4
4.10 Sealing assembly elements (see 6.7). 4
4.11 Clearances . 4
4.12 Hydraulic friction loss (see 6.8) . 6
4.13 Endurance (see 6.9) . 6
5 Production testing and quality control . 6
6 Tests . 7
6.1 Samples . 7
6.2 Spring test . 7
6.3 Body strength test (see 4.5) . 7
6.4 Valve leakage and deformation tests (see 4.8) . 7
6.4.1 Body leakage test . 7
6.4.2 Valve leakage and deformation test . 7
6.5 Warm water aging test for non-metallic components (excluding gaskets and seals
and other elastomeric parts) (see 4.9) . 8
6.6 Air aging test for non-metallic components (excluding gaskets and seals and other
elastomeric parts) (see 4.9) . 8
6.7 Sealing element tests (see 4.10) . 9
6.7.1 Release test . 9
6.8 Hydraulic friction loss test (see 4.12) . 9
6.9 Endurance test (see 4.13) . 9
6.10 Salt mist corrosion test (See 4.11) .10
6.10.1 Reagents .10
6.10.2 Apparatus .10
6.10.3 Procedure .10
7 Marking .10
8 Manufacturer’s installation instructions .11
Annex A (normative) Tolerances .12
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
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ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
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on the ISO list of patent declarations received (see www .iso .org/ patents).
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expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 21, Equipment for fire protection and fire
fighting, Subcommittee SC 5, Fixed firefighting systems using water.
This second edition cancels and replaces the first edition (ISO 6182-6:2006), which has been technically
revised.
A list of all the parts in the ISO 6182 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2020 – All rights reserved

Introduction
This document is part of the ISO 6182 series of standards covering requirements and test methods
for check valves in the main water way to a sprinkler installation. Check valves are used to prevent
the backflow of water and may be installed in several locations within a sprinkler system, e.g. if the
sprinkler system is fed from multiple pumps or if sprinkler installations are provided with multiple flow
switches for better fire localization.
INTERNATIONAL STANDARD ISO 6182-6:2020(E)
Fire protection — Automatic sprinkler systems —
Part 6:
Requirements and test methods for check valves
1 Scope
This document specifies performance, requirements, test methods and marking requirements, for
check valves used to supply water in automatic fire protection systems.
It is not applicable to trim valves.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 898-1, Mechanical properties of fasteners made of carbon steel and alloy steel — Part 1: Bolts, screws
and studs
ISO 898-2, Mechanical properties of fasteners — Part 2: Nuts with specified proof load values — Coarse thread
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
check valve
valve that allows fluid flow in one direction only
3.2
clapper
type of sealing element
Note 1 to entry: See also sealing assembly (3.7).
3.3
corrosion-resistant material
1)
bronze, brass, Monel® metal, austenitic stainless steel, or equivalent metallic or plastic material
conforming with the requirements of this document
1) Monel® is a trademark of Special Metals Corporation and is an example of a suitable product available
commercially. This information is given for the convenience of users of this document and does not constitute an
endorsement by ISO of this product. Equivalent products may be used if they can be shown to lead to the same
results.
3.4
flow velocity
speed of water flow through a valve expressed as the equivalent water velocity through a pipe of the
same nominal size as the valve
3.5
rated working pressure
maximum service pressure at which a check valve is intended to operate
3.6
reinforced elastomeric element
element of clapper, clapper assembly or seat seals in a composite of an elastomeric compound with one
or more other components
3.7
sealing assembly
main movable sealing element (such as a clapper) of the valve which prevents the reverse flow of air or
water which maintains pressure in the system piping
Note 1 to entry: See also clapper (3.2).
3.8
sealing assembly seat ring
main fixed sealing element of a valve which prevents the reverse flow of water and which maintains
pressure in the system piping
4 Requirements
4.1 Nominal sizes
The nominal size of a valve shall be the nominal diameter of the inlet and outlet connections, i.e. the
pipe size for which the connections are intended. Sizes shall be not less than DN 25. The diameter of the
waterway through the sealing assembly seat ring shall be permitted to be less than the nominal size.
4.2 Connections
4.2.1 All connections shall be designed for use at the rated working pressure of the valve.
4.2.2 The dimensions of all connections shall conform with the applicable requirements of International
Standards. If International Standards are not applicable, national standards may be used.
4.3 Rated working pressure
4.3.1 The rated working pressure shall be not less than 1,2 MPa (12 bar).
4.3.2 The rated working pressure shall be specified by the manufacturer.
4.3.3 Inlet and outlet connections shall be permitted to be machined for lower working pressures to
match installation equipment provided the valve is marked with the lower working pressure.
4.4 Bodies and covers
4.4.1 Bodies and covers shall be made of a material having corrosion resistance at least equivalent to
cast iron.
2 © ISO 2020 – All rights reserved

4.4.2 Cover fasteners shall be made of steel, stainless steel, titanium, or other materials with equivalent
physical and mechanical properties.
4.4.3 Non-metallic materials other than gaskets, diaphragms and seals or metals with a melting point
less than 800 °C shall not form part of the valve body or cover.
4.4.4 For valves with a cover plate, it shall not be possible to assemble the valve with the cover plate in
a position which either improperly indicates flow direction or prevents proper operation of the valve.
4.5 Strength (see 6.3)
4.5.1 An assembled valve, with the sealing assembly blocked open, shall withstand, without rupture,
an internal hydrostatic pressure of four times the rated working pressure for a period of 5 min, when
tested as specified in 6.3.
4.5.2 If the test in accordance with 6.3 is not done with standard production fasteners, the supplier
shall provide documentation showing that the calculated design load of any standard production
fastener, neglecting the force required to compress the gasket, does not exceed the minimum tensile
strength specified in ISO 898-1 and ISO 898-2 when the valve is pressurized to four times the rated
working pressure. The area of the application of pressure shall be calculated as follows.
a) If a full-face gasket is used, the area of application of pressure is that extending out to a line defined
by the inner edge of the bolts.
b) If an “O”-ring seal or ring gasket is used, the area of application of force is that extending out to the
centre line of the “O”-ring or gasket.
4.6 Access for maintenance
Means shall be provided to permit access to working parts and removal of the sealing assembly.
4.7 Components
4.7.1 Any component which is normally disassembled during servicing shall be designed so that it
cannot be reassembled improperly without providing an external visual indication, when the valve is
returned to service.
4.7.2 With the exception of valve seats, all parts intended for field replacement shall be capable of
being disassembled and reassembled using tools normally employed by the trade.
4.7.3 All components shall be non-detachable during normal operation of the valve.
4.7.4 Failure of the sealing assembly diaphragms or seals shall not prevent the valve from opening.
4.7.5 Seat surfaces of sealing assemblies, including the sealing assembly seat ring, shall have corrosion
resistance equivalent to brass or bronze and have sufficient width of surface contact to withstand
ordinary wear and tear, rough usage, compression stresses and damage due to pipe scale or foreign
matter carried by the water.
4.7.6 Springs and diaphragms shall not fracture or rupture, when tested in accordance with 6.2.
4.7.7 There shall be no sign, on visual examination, of damage to the sealing assembly after testing for
the operational requirements in accordance with 6.9.
4.7.8 When wide open, the sealing assembly shall bear against a definite stop. The opening of the valve
or reaction of the water shall not permanentl
...