SIST EN ISO 10497:2023

SLOVENSKI STANDARD
oSIST prEN ISO 10497:2021
01-september-2021
Preskušanje ventilov - Zahteve za protipožarno preskušanje (ISO/DIS 10497:2021)
Testing of valves - Fire type-testing requirements (ISO/DIS 10497:2021)
Prüfung von Armaturen - Anforderungen an die Typprüfung auf Feuersicherheit (ISO/DIS
10497:2021)
Essais des appareils de robinetterie - Exigences de l'essai au feu (ISO/DIS 10497:2021)
Ta slovenski standard je istoveten z: prEN ISO 10497
ICS:
13.220.40 Sposobnost vžiga in Ignitability and burning
obnašanje materialov in behaviour of materials and
proizvodov pri gorenju products
23.060.01 Ventili na splošno Valves in general
oSIST prEN ISO 10497:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 10497:2021

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oSIST prEN ISO 10497:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 10497
ISO/TC 153 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2021-06-09 2021-09-01
Testing of valves — Fire type-testing requirements
Essais des appareils de robinetterie — Exigences de l'essai au feu
ICS: 23.060.01
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 10497:2021(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
©
PROVIDE SUPPORTING DOCUMENTATION. ISO 2021

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COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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oSIST prEN ISO 10497:2021
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Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Test conditions . 3
4.1 Direction and conditions for valves to be tested . 3
4.2 Pressure relief provision . 3
5 Fire test method . 4
5.1 General warning . 4
5.2 Principle . 4
5.3 Apparatus . 4
5.3.1 General. 4
5.3.2 Specific apparatus . 4
5.4 Test fluid . 5
5.5 Test fuel . 5
5.6 Procedure . 5
6 Performance .11
6.1 General .11
6.2 Through-seat leakage during burn period .11
6.3 External leakage during burn and cool-down periods .11
6.4 Low-pressure test through-seat leakage after cool down .11
6.5 Operability .12
6.6 External leakage following operational test .12
6.7 Test report .12
7 Qualification of other valves by representative size, pressure rating, design
considerations and materials of construction . .14
7.1 General .14
7.2 Design considerations.14
7.3 Materials of construction .15
7.4 Decisions by purchaser .16
7.5 Qualification of valves by nominal size and pressure rating .16
8 Special marking .17
Bibliography .18
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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
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
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
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
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 153, Valves.
This fourth edition cancels and replaces the third edition (ISO 10497:2010), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— clarification and emphasised importance around the monitoring of cavity pressure during testing
for double seated valves;
— catering for the testing of valves with more than one obturator;
— update of the qualification of other valves by “materials of construction” and inclusion of a new
“design” clause;
— accepted fire test certificates of valves tested according to ISO 10497:2010.
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.
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Introduction
This document covers the requirements and method for evaluating the performance of valves when they
are exposed to defined fire conditions. The performance requirements establish limits of acceptability
of a valve, regardless of size, material or pressure rating. The burn period has been established to
represent the maximum time required to extinguish most fires. Fires of longer duration are considered
to be of major magnitude, with consequences greater than those anticipated in the test.
The test pressure during the burn is set at 0,2 MPa (2 bar) for soft-seated valves rated PN 10, PN 16,
PN 25 and PN 40, Class 150 and Class 300, to better simulate the conditions that would be expected in
a process plant when a fire is detected, and pumps are shut down. In this case, the source of pressure
in the system is the hydrostatic head resulting from liquid levels in towers and vessels. This situation is
approximated by this lower test pressure.
In production facilities, valves are typically of a higher rating and the pressure source is not easily
reduced when a fire is detected. Therefore, for all other valves, the test pressure during the burn is set
at a higher value to better simulate the expected service conditions in these facilities.
Use of this document assumes that the execution of its provisions is entrusted to appropriately qualified
and experienced personnel, because it calls for procedures that can be injurious to health, if adequate
precautions are not taken. This document refers only to technical suitability and does not absolve the
user from legal obligations relating to health and safety at any stage of the procedure.
This document highlights the importance of accurate monitoring and recording of test data during
fire testing. The monitoring and measuring of cavity pressure has been emphasised for all double
seated valves. Empirical evidence has shown that the cavity pressure during a fire test can increase
significantly unless relieved internally (by design) or externally. Without meeting the minimum
requirements of the test report, valves cannot be certified as a fire safe design to this document.
It is recognised by this document that not all combinations of potential trim arrangements can be
covered by a single fire test report. Certain design or material differences can be accepted by the
purchaser if they do not influence sealing or operating performance. Further clarification on soft
materials grouping and bolting has been included in this document.
Valves with more than one obturator are regularly used for in-line isolation and instrumentation
service. As such, the need to qualify such designs as fire safe certified is now a common requirement.
This document now caters for such valve designs.
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oSIST prEN ISO 10497:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 10497:2021(E)
Testing of valves — Fire type-testing requirements
1 Scope
This document specifies fire type-testing requirements and a fire type-test method for valves with
one or more obturators. It is not applicable to the testing requirements for valve actuators other
than manually operated gearboxes or similar mechanisms when these form part of the normal valve
assembly. Other types of valve actuators (e.g. electrical, pneumatic or hydraulic) can need special
protection to operate in the environment considered in this valve test, and the fire testing of such
actuators is outside the scope of this document.
This document specifies the measurement and assessment criteria for:
a) through-seat leakage;
b) external leakage;
c) cavity overpressure relief of double seated valves;
d) operability.
This document specifies the rules whereby the fire-type testing qualification for a valve can be extended
to untested sizes, pressure ratings, and materials of construction of the same basic design type.
Fire test reports of valves tested according to previous editions of ISO 10497 are acceptable when
submitted together with the full and compliant fire test report as per 6.7 of the edition under which it
was tested. Additional testing is specified for double seated valves where the body cavity relief valve
setting was not recorded in the original fire test report.
NOTE For the purposes of this document, the terms “fire type-test” and “fire test” are synonymous.
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.
IEC 60584-2, Thermocouples — Part 2: Tolerances
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 https:// www .electropedia .org/
3.1
nominal size
DNalphanumeric designation of size for components of a pipework system, which is used for reference
purposes, comprising the letters DN followed by a dimensionless whole number which is indirectly
related to the physical size, in millimetres, of the bore or outside diameter of the end connections
[SOURCE: ISO 6708:1995, definition 2.1]
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3.2
nominal pressure
PN
numerical designation relating to pressure which is a convenient rounded number for reference
purposes, and which comprises the letters PN followed by the appropriate reference number
Note 1 to entry: It is intended that all equipment of the same nominal size (DN) designated by the same PN
number have compatible mating dimensions.
Note 2 to entry: The maximum allowable pressure depends on materials, design and working temperatures, and
is selected from the tables of pressure/temperature ratings given in the appropriate standards.
[SOURCE: ISO 7268:1983, Clause 2, modified.]
3.3
NPS
alphanumeric designation of size for components of a pipework system, which is used for reference
purposes, and which comprises the letters NPS followed by a dimensionless number indirectly related
to the physical size of the bore or outside diameter of the end connections
Note 1 to entry: The number following the letters NPS does not represent a measurable value and is not intended
to be used for calculation purposes except where specified in the relevant standard.
3.4
Class
alphanumeric designation used for reference purposes related to a combination of mechanical and
dimensional characteristics of a component of a pipework system, which comprises the word “Class”
followed by a dimensionless whole number
Note 1 to entry: The number following the word “Class” does not represent a measurable value and is not intended
to be used for calculation purposes except where specified in the relevant standard.
3.5
symmetric seated valve
valve with an internal construction, which has a plane of symmetry perpendicular to the axis of the
body ends
Note 1 to entry: This is a valve where both seat and sealing elements are identical.
3.6
asymmetric seated valve
valve with an internal construction, which has no plane of symmetry perpendicular to the axis of the
body ends
Note 1 to entry: This is a valve with a single seat offset from the shaft centreline or containing a twin seated
arrangement where both seats are not identical such as one bi-directional seat and one self-relieving seat.
3.7
soft seated
seat or sealing element made from, or including, thermoplastic, polymeric or elastomeric material
3.8
obturator
movable component of the valve whose position in the fluid flow path permits, restricts or obstructs
the fluid flow
3.9
double seated valve
valve which utilises two seats for each obturator, resulting in a cavity, such as a trunnion mounted or
floating ball valve, gate valve, plug valve
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4 Test conditions
4.1 Direction and conditions for valves to be tested
4.1.1 Symmetric seated valves intended by the manufacturer for bi-directional installation shall be
tested in one direction only.
4.1.2 Asymmetric seated valves intended by the manufacturer for bi-directional installation shall be
tested by carrying out the burn test procedure twice, once in each direction of the potential installation.
The same valve may be refurbished and re-tested, or another, identical, valve may be tested in the other
direction.
4.1.3 Valves intended solely for unidirectional installation shall be clearly and permanently marked as
such, and shall be tested in the stated direction of installation.
4.1.4 If the valve being tested is fitted with a gearbox or other such manual device, only that particular
assembly shall qualify. If a valve can be supplied with or without a gearbox, testing with a gearbox fitted
shall qualify valves without a gearbox, but not the converse.
4.1.5 Valves (and gearboxes) shall not be protected with insulation material of any form during testing,
except where such protection is part of the design of the component(s).
4.1.6 For valves with more than one obturator, if all seals and obturators are of the same design,
through-seat leak testing of the upstream obturator in a single direction shall qualify all obturators in
both directions. Asymmetric valves shall be tested on the upstream block in both directions.
For valves with more than one obturator, a qualified assembly is one where all obturators have been
qualified in single valves that use the same obturator and seat/ seal design.
If required by the purchaser, tests of a complete manifold assembly shall be subject to agreement
between purchaser and manufacturer. The test procedure used shall be agreed by all parties.
The complete assembly, including any auxiliary connections, vents, drains shall be subjected to the
fire. The upstream obturator shall be in the closed position and the downstream obturator shall be in
the partially open position throughout the test. Testing for external leakage shall be on the complete
assembly.
If the valve comprises of an external vent valve, this shall be in the closed position. All other auxiliary
connections shall be blinded sufficiently.
4.2 Pressure relief provision
4.2.1 If the valve under test incorporates a means of relieving cavity pressure as part of its standard
design and if this provision activates during the fire test, the test shall be continued and any leakage to
atmosphere from the provision shall be measured and counted as external leakage. If the design is such
that the provision vents to the downstream side of the valve, any leakage shall be counted as through-
seat leakage (see 5.6.11 and 5.6.13).
4.2.2 The test shall be stopped and considered void if the cavity pressure is exceeded which activates
the relief valve described in 5.3.2.8.
4.2.3 Double seated valves tested in compliance with a previous edition of this document where the
body cavity relief valve setting and/or cavity pressure during testing was not recorded in the original
test report shall be subjected to a supplementary test before claiming compliance with this edition.
An overpressure cavity relief test at ambient conditions shall be undertaken to demonstrate the relief
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performance mechanism of the valve with the test report appended to the original fire test report. Test
pressure shall be as specified in 5.3.2.8.
5 Fire test method
5.1 General warning
Fire testing of valves is potentially hazardous and it is essential that the safety of personnel be given
prime consideration. Given the nature of the fire test and the possibility of weaknesses in the design of
the test valve and test equipment, hazardous rupture of the pressure boundary could occur. Adequate
shields in the area of the test enclosure and other appropriate means for the protection of personnel are
necessary.
Fire testing shall be void if the product or system fails to perform within the limits specified, except
when such failure is determined to be the result of a failure within the test facility or test fixture and
that failure and its correction do not affect the validity of the test results.
5.2 Principle
A closed valve, completely filled with water under pressure, is completely enveloped in flames with
an environmental temperature in the region of the valve of 750 °C to 1 000 °C for a period of 30 min.
The objective is to completely envelop the valve in flames to assure that the seat and sealing areas
are exposed to the high burn temperature. The intensity of the heat input shall be monitored using
thermocouples and calorimeter cubes as specified in 5.6.7 and 5.6.8. During this period the internal
and external leakage is recorded. After cool-down from the fire test, the valve is hydrostatically tested
to assess the pressure containing capability of the valve shell, seats and seals.
5.3 Apparatus
5.3.1 General
The test equipment shall not subject the valve to externally applied stress affecting the results of the test.
Schematic diagrams of recommended systems for fire type-testing of valves are given in Figure 1.
Potential pipework-to-valve end connection joint leakage is not evaluated as part of the test and is not
included in the allowable external leakage (see 6.3 and 6.6). For the purposes of this test, it may be
necessary to modify these joints to eliminate leakage.
The test equipment shall be designed such that if the nominal diameter of the pipework situated
immediately upstream of the test valve is larger than DN 25 or one-half the DN of the test valve, the
pipework shall be enveloped in flames for a minimum distance of 150 mm from the test valve. The
diameter of the upstream pipework shall be sufficient to deliver a flow rate in excess of the maximum
allowable leak rate for the size of the valve being tested.
The pipework downstream of the test valve shall be at least DN 15 and shall be inclined such that the
downstream side is fully drained.
The flame source shall be at least 150 mm minimum away from the valve or any calorimeters, and
should have sufficient capacity to completely envelop the valve in flames.
The enclosure containing the valve shall provide a horizontal clearance of a minimum of 150 mm
between any part of the test valve and the enclosure, and the height of the enclosure above the top of
the test valve shall be a minimum of 150 mm.
5.3.2 Specific apparatus
5.3.2.1 Vapour trap, to minimize the cooling effect of the upstream liquid. See Figure 1 (7).
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NOTE In 5.3.2 and 5.6, the numbered items in parentheses refer to the item numbers for the apparatus in
Figure 1.
5.3.2.2 Industrial pressure measurement devices having a full-scale reading of between 1,5 and 4
times the pressure being measured. The accuracy of each test device used at any point on the scale shall
be within 3 % of its maximum scale value for readings taken both up and down the scale, with either
increasing or decreasing pressure. See Figure 1 (6, 12).
5.3.2.3 Calorimeter cubes, of carbon steel in accordance with the design and dimensions shown in
Figure 2, with a thermocouple of the accuracy specified in 5.3.2.4, located in the centre of each cube.
Calorimeter cubes shall be scale-free before exposure to the fire environment.
5.3.2.4 Flame environment and valve body thermocouples, of an accuracy at least equal to tolerance
class 2 for type B or tolerance class 3 for other types, as specified in IEC 60584-2. See Figure 1 (11).
5.3.2.5 Containers, of a size suitable for collecting the water leaked from the valve under test. See
Figure 1 (16).
5.3.2.6 Calibrated sight gauge, or device for measuring the water volume used during the test. See
Figure 1 (4).
5.3.2.7 Calibrated device for measuring the leakage water collected during the test.
5.3.2.8 Pressure relief valve, incorporated in the system, to relieve test valve cavity overpressure due
to thermal expansion of test liquid to the atmosphere, to protect against potential rupture, is required for
all double seated valves. For valves with more than one obturator, the connection shall be made into the
cavity of the upstream obturator.
The set pressure of the relief valve during the fire test and therefore the maximum allowable cavity
pressure of the valve during the test shall be:
— either that determined by the valve manufacturer from data obtained by hydrostatic cavity
overpressure testing of the test valve; proof of this required value is required prior to testing and
shall be documented within the report [see 6.7 x)]; or
— when pressure te
...