kSIST FprEN ISO 23826:2021

Gas cylinders - Ball valves - Specification and testing (ISO/FDIS 23826:2021)

This document specifies design, type testing, marking and manufacturing test and examination
requirements for ball valves used as:
a) closures of refillable transportable gas cylinders, pressure drums and tubes;
b) main valves for cylinder bundles;
c) valves for cargo transport units (e.g. trailers, battery vehicles and MEGCs);
which convey compressed gases, liquefied gases and dissolved gases.
NOTE 1 In the course of the document, the term "valve" is used with the meaning of "ball valve".
This document does not apply to:
•   oxidizing gases as defined in ISO 10156,
•   toxic gases (i.e. gases listed in ISO 10298 having an LC50 value ≤ 5 000 ppm) and
•   acetylene for single gas cylinders, pressure drums and tubes.
NOTE 2 The reason for the exclusion of oxidizing gases is that the use of ball valves as closures of high
pressure cylinders for oxidizing gases is known to lead to specific ignition hazards that cannot reasonably be mitigated through the ball valve design or type testing. Safety hazards concern both the ball valve itself and any downstream equipment.
This International document does not apply to ball valves for liquefied petroleum gas (LPG),
cryogenic equipment, portable fire extinguishers and cylinders for breathing apparatus.
NOTE 3 Requirements for valves for cryogenic vessels are specified in ISO 21011 and at a regional level, e.g. in EN 1626. Requirements for valves for portable fire extinguishers at a regional level are specified e.g. in EN 3 series.
NOTE 4 Certain specific requirements for valves for breathing apparatus in addition to those that are
given in this document are specified at a regional level, e.g. in EN 144 series. Certain specific requirements for quick-release valves for fixed fire-fighting systems in addition to those that are given in this document are specified in ISO 16003 and at a regional level e.g. in EN 12094–4.

Gasflaschen - Kugelhähne - Spezifikation und Prüfungen (ISO/FDIS 23826:2021)

Bouteilles à gaz - Robinets à boisseau sphérique - Spécifications et essais (ISO/FDIS 23826:2021)

Plinske jeklenke - Krogelne pipe - Specifikacija in preskušanje (ISO/FDIS 23826:2021)

General Information

• Status: Not Published
• Public Enquiry End Date: 01-Apr-2021
• ICS: 23.020.35 - Gas cylinders
• ICS: 23.060.20 - Ball and plug valves
• Technical Committee: TLP - Pressure vessels
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 07-Sep-2021
• Due Date: 26-Oct-2021
• Completion Date: 29-Sep-2021
• Mandate: M/TDG - Standards for referencing in the RID-ADR
• Ref Project: EN ISO 23826:2021 - Gas cylinders - Ball valves - Specification and testing (ISO 23826:2021)

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 23826:2021
01-marec-2021
Plinske jeklenke - Krogelni ventili - Specifikacija in preskušanje (ISO/DIS
23826:2021)
Gas cylinders - Ball valves - Specification and testing (ISO/DIS 23826:2021)
Gasflaschen - Kugelhähne - Spezifikation und Prüfungen (ISO/DIS 23826:2021)
Ta slovenski standard je istoveten z: prEN ISO 23826
ICS:
23.020.35 Plinske jeklenke Gas cylinders
23.060.20 Zapirni ventili (kroglasti in Ball and plug valves
pipe)
oSIST prEN ISO 23826:2021 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 23826:2021
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oSIST prEN ISO 23826:2021
DRAFT INTERNATIONAL STANDARD
ISO/DIS 23826
ISO/TC 58/SC 2 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2021-01-14 2021-04-08
Gas cylinders — Ball valves — Specification and testing
ICS: 23.020.35
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 23826:2021(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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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
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

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
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Valve description .................................................................................................................................................................................................. 4

5 Valve design requirements ........................................................................................................................................................................ 6

5.1 General ........................................................................................................................................................................................................... 6

5.2 Materials ....................................................................................................................................................................................................... 7

5.3 Valve connections ................................................................................................................................................................................. 7

5.4 Mechanical strength ........................................................................................................................................................................... 8

5.4.1 Resistance to hydraulic burst pressure ........................................................................................................ 8

5.4.2 Resistance to mechanical impact ....................................................................................................................... 8

5.5 Valve operating mechanism ......................................................................................................................................................... 8

5.6 Valve operating device ...................................................................................................................................................................... 9

5.7 Leakage .......................................................................................................................................................................................................... 9

5.8 Securing arrangements .................................................................................................................................................................... 9

5.9 Manufacturing tests and examinations ...........................................................................................................................10

6 Type testing.............................................................................................................................................................................................................10

6.1 General ........................................................................................................................................................................................................10

6.2 Documentation ....................................................................................................................................................................................12

6.3 Test samples ...........................................................................................................................................................................................12

6.4 Test report ................................................................................................................................................................................................13

6.5 Test temperatures .............................................................................................................................................................................13

6.6 Test pressures .......................................................................................................................................................................................13

6.6.1 Valve burst test pressure .......................................................................................................................................13

6.6.2 Valve test pressure ......................................................................................................................................................13

6.7 Test gases ..................................................................................................................................................................................................13

6.7.1 Gas quality ..........................................................................................................................................................................13

6.7.2 Leak tightness tests ....................................................................................................................................................14

6.7.3 Endurance tests .............................................................................................................................................................14

6.8 Test schedule .........................................................................................................................................................................................14

6.9 Hydraulic burst pressure test ..................................................................................................................................................15

6.10 Flame impingement test ..............................................................................................................................................................15

6.11 Excessive torque test ......................................................................................................................................................................15

6.12 Leak tightness test ............................................................................................................................................................................16

6.12.1 General...................................................................................................................................................................................16

6.12.2 Internal leak tightness test .................. .................................................................................................................16

6.12.3 External leak tightness test..................................................................................................................................17

6.13 Endurance test .....................................................................................................................................................................................17

6.14 Visual examination ...........................................................................................................................................................................18

7 Marking .......................................................................................................................................................................................................................18

8 Operating instructions ................................................................................................................................................................................19

Annex A (normative) Manufacturing tests and examinations ................................................................................................20

Annex B (normative) Endurance test machine .......................................................................................................................................21

Bibliography .............................................................................................................................................................................................................................23

© ISO 2021 – All rights reserved iii
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
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 58 Gas cylinders, Subcommittee SC 2,

Cylinder fittings.
This is the first edition.

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 2021 – All rights reserved
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
Introduction

This document covers the function of a ball valve as a closure (defined by the UN Model Regulations).

Additional features of ball valves (e.g. pressure regulators, residual pressure devices, non-return

devices and pressure relief devices) might be covered by other standards and/or regulations.

Ball valves complying with this document can be expected to perform satisfactorily under normal

service conditions.
This document pays particular attention to:

a) safety (mechanical strength, impact strength, endurance, leak tightness, resistance to acetylene

decomposition);
b) suitability of materials;
c) testing;
d) marking.

This document has been written so that it is suitable to be referenced on the UN Model Regulations

[1]. In this document the unit bar is used, due to its universal use in the field of technical gases. It

should, however, be noted that bar is not an SI unit, and that the corresponding SI unit for pressure is Pa

5 5 2
(1 bar = 10 Pa = 10 N/m ).

Pressure values given in this document are given as gauge pressure (pressure exceeding atmospheric

pressure) unless noted otherwise.
Any tolerances given in this document include measurement uncertainties.
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oSIST prEN ISO 23826:2021
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oSIST prEN ISO 23826:2021
DRAFT INTERNATIONAL STANDARD ISO/DIS 23826:2021(E)
Gas cylinders — Ball valves — Specification and testing
1 Scope

This document specifies design, type testing, marking and manufacturing test and examination

requirements for ball valves used as:
a) closures of refillable transportable gas cylinders, pressure drums and tubes;
b) main valves for cylinder bundles;
c) valves for cargo transport units (e.g. trailers, battery vehicles and MEGCs);
which convey compressed gases, liquefied gases and dissolved gases.

NOTE 1 In the course of the document, the term “valve” is used with the meaning of “ball valve”.

This document does not apply to ball valves for:
• oxidizing gases as defined in ISO 10156,

• toxic gases (i.e. gases listed in ISO 10298 having an LC value ≤ 5 000 ppm) and

• acetylene for single gas cylinders, pressure drums and tubes.

NOTE 2 The reason for the exclusion of oxidizing gases is that the use of ball valves as closures of high

pressure cylinders for oxidizing gases is known to lead to specific ignition hazards that cannot reasonably be

mitigated through the ball valve design or type testing. Safety hazards concern both the ball valve itself and any

downstream equipment.

NOTE 3 The reason for the exclusion of acetylene for single gas cylinders, pressure drums and tubes is that the

risk of an acetylene decomposition cannot reasonably be mitigated through the ball valve design or type testing.

This document does not apply to ball valves for liquefied petroleum gas (LPG), cryogenic equipment,

portable fire extinguishers and cylinders for breathing apparatus.

NOTE 4 Requirements for valves for cryogenic vessels are specified in ISO 21011 and at a regional level,

e.g. in EN 1626. Requirements for valves for portable fire extinguishers at a regional level are specified e.g. in

EN 3 series.

NOTE 5 Certain specific requirements for quick-release valves for fixed fire-fighting systems in addition to

those that are given in this document are specified in ISO 16003 and at a regional level e.g. in EN 12094–4.

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 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method

ISO 10156, Gas cylinders — Gases and gas mixtures — Determination of fire potential and oxidizing ability

for the selection of cylinder valve outlets
ISO 10286, Gas cylinders — Terminology

ISO 10298, Gas cylinders — Gases and gas mixtures — Determination of toxicity for the selection of cylinder

valve outlets
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)

ISO 10524-3, Pressure regulators for use with medical gases — Part 3: Pressure regulators integrated with

cylinder valves (VIPRs)

ISO 11114-1, Gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 1:

Metallic materials

ISO 11114-2, Gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 2:

Non-metallic materials

ISO 14246, Gas cylinders — Cylinder valves — Manufacturing tests and examinations

ISO 15615:2013, Gas welding equipment — Acetylene manifold systems for welding, cutting and allied

processes — Safety requirements in high-pressure devices

ISO 22435, Gas cylinders — Cylinder valves with integrated pressure regulators — Specification and

type testing
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 10286 and the following 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
ball valve

valve which uses the rotation of a ball with a through-passage to allow or shut-off flow through it

Note 1 to entry: Ball valves can have multiple ports.
3.2
main valve

valve which is fitted to a cylinder bundle’s manifold isolating it from the main connection(s)

3.3
valve operating mechanism

mechanism which rotates the ball and which includes external sealing systems and can

include the internal sealing systems
3.4
valve operating device
component which actuates the valve operating mechanism (3.3)
Note 1 to entry: Examples are handle/lever, handwheel/knob, key or actuator.
3.5
stop mechanism
system which limits the position of the valve operating mechanism (3.3)

Note 1 to entry: Examples are stop pin and stop plate, mechanical stop in valve body and counterpart in

handle/lever.
3.6
external leak tightness

leak tightness to atmosphere (leakage in and/or leakage out) when the valve is open

3.7
internal leak tightness

leak tightness across the seat (leakage in and/or leakage out) when the valve is closed

2 © ISO 2021 – All rights reserved
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
3.8
valve working pressure

settled pressure of a compressed gas at a uniform reference temperature of 15 °C in a full pressure

receptacle for which the valve is intended

Note 1 to entry: This definition does not apply to liquefied gases (e.g. carbon dioxide), or dissolved gases (e.g.

acetylene).
Note 2 to entry: The valve working pressure is expressed in bar.
3.9
valve burst test pressure
vbt
minimum pressure applied to a valve during hydraulic burst pressure test
Note 1 to entry: The valve burst test pressure is expressed in bar.
3.10
valve test pressure
minimum pressure applied to a valve during testing
Note 1 to entry: The valve test pressure is expressed in bar.
3.11
lowest operating pressure

lowest settled pressure of the gas(es) for which the ball valve is designed

3.12
endurance torque
torque used during the endurance test
Note 1 to entry: The endurance torque is expressed in Nm.
3.13
over torque

torque applied to the valve operating device (3.4) in opening and closing direction which the valve

operating mechanism (3.3) and/or stop mechanism (3.5) can tolerate and remain operable

Note 1 to entry: The over torque is expressed in Nm.
3.14
failure torque

opening or closing torque (whichever is the lower value) applied to the valve operating device (3.4) at

which mechanical failure occurs
Note 1 to entry: The failure torque is expressed in Nm.
3.15
valve inlet connection
connection on the valve which connects the valve to the pressure receptacle
3.16
valve outlet connection
connection on the valve used to discharge the pressure receptacle
Note 1 to entry: For most valves this connection is also used for filling.
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
3.17
valve filling connection
connection on the valve used to fill the pressure receptacle

Note 1 to entry: The valve filling connection can be different from the valve outlet connection.

3.18
NTP

normal temperature and pressure [20,0 °C (293,15 K), 1,013 bar absolute (0,101 3 MPa absolute)]

4 Valve description
4.1 A ball valve (see Figure 1) typically comprises of:
a) valve body;
b) valve operating mechanism;
c) valve operating device;
d) stop mechanism;
e) means to ensure internal leak tightness;
f) means to ensure external leak tightness;
g) valve outlet connection(s);
h) valve inlet connection.
4.2 Ball valves can also include:
a) pressure-relief device;

NOTE 1 The relevant transport regulation can require or forbid pressure relief devices for some gases,

gas mixtures or gas groups. Additional requirements for pressure-relief devices can exist in international/

regional regulations/standards.
b) dip tube;
c) connection plug/cap;
d) excess flow device;
e) non-return valve on the valve filling connection;
f) residual pressure device with or without non-return function;
NOTE 2 Requirements for residual pressure devices are given in ISO 15996.
g) pressure regulating device;

NOTE 3 Requirements for pressure regulating devices are given in ISO 22435 for industrial applications

and in ISO 10524-3 for medical applications.
h) separate valve filling connection;
i) flow restricting orifice;
j) filter(s).
Not all of these components have test requirements detailed in this document.
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
4.3 There are typically two ball valve types:
a) floating ball type (see Figure 2);
b) trunnion type (see Figure 3).
The valve designs shown in Figures 2 and 3 are given as typical examples only.
Key
1 stop pin
2 valve body
3 valve connection (inlet/outlet)
4 handle/lever
5 stem
6 stem sealing
7 seat
8 ball
9 stop plate
NOTE Stop plate and handle/lever can be combined in one component.
Figure 1 — Example of a ball valve design
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
Figure 2 — Floating ball type design
Figure 3 — Trunnion type design
5 Valve design requirements
5.1 General

Valves shall operate within specification and be leak tight over a range of service temperatures, from at

least −20 °C to +65 °C in indoor and outdoor environments.

Closed valves shall be internally leak tight during transport and storage (see test 6 in Table 3) for

temperatures down to −40 °C.

Where higher or lower service temperatures are required, any additional requirements and tests shall

be agreed between the manufacturer and purchaser.
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)

For ball valves used in liquefied gas service, a cavity relief system (e.g. a vent through the ball) is

required to prevent trapping of the gas within the ball cavity in the closed condition.

For ball valves with multiple ports, the relevant requirements according to Clause 5 shall be fulfilled for

each port.

For ball valves where anti-static and fire safe behaviour is of importance, examples of respective

requirements are given in Annex B of EN 12266-2 and in ISO 10497.
5.2 Materials

Metallic and non-metallic materials in contact with the gas shall be chemically and physically compatible

with the gas, according to ISO 11114-1 and ISO 11114-2 under all intended operating conditions. For

all valves, the compatibility of the lubricant(s) and glue(s), if used in gas wetted areas, shall also be

considered. For valves used for dissolved gases, the compatibility of the materials in contact with the

solvent shall also be considered. For valves used with gas mixtures, the compatibility of the gas wetted

materials with each component of the gas mixture shall be considered.

When using plated or coated components in gas wetted areas the material compatibility of both

the plating/coating material and the substrate material shall be taken into account. In addition,

consideration should be given to avoid separation of the surface coating or particle generation.

The material used for the valve body shall be either

a) a material not showing a ductile to brittle transition (examples of allowed materials are copper

alloys, austenitic stainless steels, aluminium alloys and nickel alloys), or

b) a ferritic material (e.g. carbon steel) having an impact value greater than 27 J at −40 °C when

submitted to the Charpy pendulum impact test as specified in ISO 148-1.
5.3 Valve connections

Valve inlet and outlet connections shall conform to an International Standard, other regional or national

standards or proprietary designs that have been qualified to an acceptable industry standard.

NOTE 1 Valve inlet connection standards are for example ISO 11363-1, ISO 15245-1, ISO 228, ISO 6162-1,

ISO 6162-2, ISO 11926-1 and ANSI/ASME B1.20.1.

NOTE 2 International valve outlet connection standards are for example ISO 5145, ISO 10692-1, ISO 228–1,

ISO 6162-1, ISO 6162-2, ISO 11926-1 and ANSI/ASME B1.20.1. A partial compilation of regional and national

standards is given in ISO/TR 7470.

NOTE 3 Qualification procedures for proprietary valve inlet connection designs are for example given in

ISO 10692-2.

NOTE 4 Qualification procedures for proprietary valve outlet connection designs are for example given in

CGA V-1.

If the valve filling connection is separate to the valve outlet connection and not equipped with a closure

device (non-return valve or isolating valve), it shall be provided with a pressure-tight device (e.g. a plug

or cap which can be operated or removed only by the use of a special proprietary tool provided by

the manufacturer). Where applicable, such a pressure-tight device shall be designed to vent gas before

becoming disengaged.

The valve filling connection closure device, if fitted, shall comply with the relevant endurance and

subsequent leakage requirements of ISO 22435 for industrial applications or ISO 10524-3 for medical

applications.
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oSIST prEN ISO 23826:2021
ISO/DIS 23826:2021(E)
5.4 Mechanical strength
5.4.1 Resistance to hydraulic burst pressure

Valves shall withstand p (see 6.6.1) without permanent visible deformation or burst.

vbt
The hydraulic burst pressure test is given in 6.9.
5.4.2 Resistance to mechanical impact

This document does not include a test to validate that the valve is inherently able to withstand damage

from impact without release of the contents. It is recommended that ball valves are protected during

transport by valve protection caps or valve guards or other acceptable means.

NOTE Applicable transport regulations normally specify the variety of acceptable means. Main valves used

in cylinder bundles according to ISO 10961 are protected by the frame.
5.5 Valve operating mechanism

5.5.1 The valve operating mechanism shall meet the requirements of 5.5.2 to 5.5.5.

5.5
...