oSIST prEN ISO 10286:2021

Gas cylinders - Vocabulary (ISO/FDIS 10286:2021)

Gasflaschen - Terminologie (ISO/FDIS 10286:2021)

Dieses Dokument legt Begriffe für Gasflaschen fest.

Bouteilles à gaz - Vocabulaire (ISO/FDIS 10286:2021)

Plinske jeklenke - Terminologija (ISO/FDIS 10286:2021)

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Sep-2021
• ICS: 01.040.23 - Fluid systems and components for general use (Vocabularies)
• ICS: 23.020.35 - Gas cylinders
• Technical Committee: TLP - Pressure vessels
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 11-Jul-2021
• Due Date: 28-Nov-2021
• Completion Date: 29-Sep-2021
• Ref Project: prEN ISO 10286 - Gas cylinders - Vocabulary (ISO/FDIS 10286:2021)

RELATIONS

• Revised: SIST EN ISO 10286:2015 - Gas cylinders - Terminology (ISO 10286:2015)
• Effective Date: 01-Sep-2021

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN ISO 10286:2021
01-september-2021
Plinske jeklenke - Terminologija (ISO/FDIS 10286:2021)
Gas cylinders - Vocabulary (ISO/FDIS 10286:2021)
Gasflaschen - Terminologie (ISO/FDIS 10286:2021)
Bouteilles à gaz - Vocabulaire (ISO/FDIS 10286:2021)
Ta slovenski standard je istoveten z: prEN ISO 10286
ICS:
01.040.23 Tekočinski sistemi in sestavni Fluid systems and
deli za splošno rabo (Slovarji) components for general use
(Vocabularies)
23.020.35 Plinske jeklenke Gas cylinders
oSIST prEN ISO 10286:2021 en,fr,de

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

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oSIST prEN ISO 10286:2021
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oSIST prEN ISO 10286:2021
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 10286
ISO/TC 58
Gas cylinders — Vocabulary
Secretariat: BSI
Voting begins on: Bouteilles à gaz — Vocabulaire
2021­07-02
Voting terminates on:
2021­09-24
ISO/CEN PARALLEL PROCESSING
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 SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO­
ISO/FDIS 10286:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN­
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. ISO 2021
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(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
CH­1214 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 10286:2021
ISO/FDIS 10286:2021(E)
Contents Page

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

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

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

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

3 Terms and definitions ..................................................................................................................................................................................... 1

3.1 Terms related to pressure receptacles ............................................................................................................................... 1

3.1.1 All pressure receptacles............................................................................................................................................. 1

3.1.2 All gas cylinders ................................................................................................................................................................ 4

3.1.3 Composite gas cylinders ............................................................................................................................................ 4

3.1.4 Acetylene cylinders ........................................................................................................................................... ............. 4

3.1.5 Bundles of cylinders, battery vehicles and MEGC ............................................................................... 5

3.2 Terms related to accessories ....................................................................................................................................................... 6

3.3 Terms related to manufacture ................................................................................................................................................10

3.4 Terms related to testing and inspection .........................................................................................................................11

3.5 Terms related to characteristics, properties and pressures .........................................................................13

Annex A (informative) Pressure system for pressure receptacles .....................................................................................19

Annex B (informative) Terms of Clause 3 and additional terminology — Equivalent terms in

French and German ........................................................................................................................................................................................20

Annex C (informative) Figures related to the additional terminology given in Annex B ............................37

Bibliography .............................................................................................................................................................................................................................50

© ISO 2021 – All rights reserved iii
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(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 non­governmental, 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, in collaboration with

the European Committee for Standardization (CEN) Technical Committee CEN/TC 23, Transportable gas

cylinders, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna

Agreement).

This fifth edition cancels and replaces the fourth edition (ISO 10286:2015), of which it constitutes a

minor revision. The changes compared with the previous edition are as follows:
— changes to the formatting and structure throughout;
— editorial changes to fully align with the rules in ISO/IEC Directives Part 2.

In addition to terms and definitions used in the official ISO languages English and French, this document

gives the equivalent terms and definitions in German; these are published under the responsibility

of the ISO member body for Germany (DIN) and are given for information only. Only the terms and

definitions given in the official languages can be considered as ISO terms and definitions.

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 10286:2021
ISO/FDIS 10286:2021(E)
Introduction
The terms and definitions in this document are given in the following layout:
preferred term(s) in bold typeface
admitted term(s) or synonyms, in normal typeface

DEPRECATED: deprecated term deprecated term(s), in normal typeface, with the designa­

tion “DEPRECATED”:
definition the definition, where available, in normal typeface
Note 1 to entry: notes to entry, cross-references and examples.
Figures/non­verbal representations

The terms in this document are sorted in systematic order as far as possible. Further guidance on

terminological presentation can be found in ISO 10241­1.

The definitions support the understanding of the terms used in this document. They have been prepared

with due regard to possible uses in different fields related to gas cylinders. However, it is possible that

they will require adaption for particular uses.

Within this document, the term “ADR” is for simplification used as to also include similar regulations

such as RID and ADN, where appropriate.
[4]

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

Table 1 shows a hierarchical overview of pressure receptacles according to the UN Model Regulations.

Annex A shows the different pressures for pressure receptacles in relation to each other.

Annex B shows a table including equivalent terms for additional terminology.
Annex C shows figures related to the additional terminology given in Annex B.

Terms given in square brackets are not within the scope of this document. They are shown for

information only.
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
© ISO 2021 – All rights reserved vi
Table 1 — Hierarchical overview of terms for pressure receptacles
small pressure receptacle
receptacle
containing
MEGC
gas (gas
[metal­
battery (multiple­
salvage [closed a
cartridge) [tank ]
pressure bundle of hydride
vehicle element gas
cylinder tube pressure cryogenic
drum cylinders storage
and container)
receptacle receptacle ]
system ]
aerosol
dispenser
In scope of CEN/TC 296 and CEN/TC 286.
In scope of ISO/TC 220.
In scope of ISO/TC 197.
This designation is used in the ADR.

NOTE Within this document, for simplification, the use of the term “ADR” also includes similar regulations such as RID and ADN, where appropriate.

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oSIST prEN ISO 10286:2021
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 10286:2021(E)
Gas cylinders — Vocabulary
1 Scope
This document defines terms for gas cylinders.
2 Normative references
There are no normative references in this document.
3 Terms and definitions

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 Terms related to pressure receptacles
3.1.1 All pressure receptacles
3.1.1.1
pressure receptacle
DEPRECATED: receptacle

cylinder, tube, pressure drum, closed cryogenic receptacle, metal-hydride storage system, bundle of

cylinders or salvage pressure receptacle
Note 1 to entry: A seamless gas cylinder is an example of a pressure receptacle:
3.1.1.2
gas cylinder
cylinder
transportable pressure receptacle of a water capacity not exceeding 150 l

Note 1 to entry: In ISO/TC 58 standards, the term “gas cylinder” is frequently used for clarification.

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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.1.1.3
tube

seamless transportable pressure receptacle of a water capacity exceeding 150 l but not more than

3 000 l

Note 1 to entry: In ISO/TC 58, standards for composite tubes also with a higher water capacity are under

development.
3.1.1.4
pressure drum

welded transportable pressure receptacle of a water capacity exceeding 150 l and of not more than

1 000 l
3.1.1.5
bundle of cylinders
cylinder bundle
DEPRECATED: cylinder pack

assembly of cylinders that are fastened together and which are interconnected by a manifold and

transported as a unit having a total water capacity not exceeding 3 000 l except that bundles intended

for the transport of toxic gases shall be limited to 1 000 l total water capacity

Note 1 to entry: In ISO/TC 58 standards, the term “bundle” is frequently used for simplification.

EXAMPLE
3.1.1.6
salvage pressure receptacle

pressure receptacle with a water capacity not exceeding 1 000 l into which are placed damaged,

defective, leaking or non­conforming pressure receptacle(s) for the purpose of transport, e.g. for

recovery or disposal
3.1.1.7
small receptacle containing gas
gas cartridge

non-refillable receptacle having a water capacity not exceeding 1 000 ml for receptacles made of metal

and not exceeding 500 ml for receptacles made of synthetic material or glass, containing under pressure

a gas or mixture of gases

Note 1 to entry: This definition is used in the ADR only. There is no definition in the UN Model Regulations.

Note 2 to entry: This note applies to the German language only.
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.1.1.8
aerosol dispenser
aerosol

non-refillable receptacle made of metal, glass or plastics and containing a gas, compressed, liquefied

or dissolved under pressure, with or without a liquid, paste or powder and fitted with a release device

allowing the contents to be ejected
Note 1 to entry: This note applies to the German language only.
EXAMPLE
3.1.1.9
metal-hydride storage system

single complete hydrogen storage system, including a receptacle, metal hydride, pressure relief device,

shut-off valve, service equipment and internal components used for the transport of hydrogen only

3.1.1.10
cryogenic receptacle

transportable thermally insulated receptacle for refrigerated liquefied gases, of a water capacity of not

more than 1 000 l
3.1.1.11
MEGC
multiple-element gas container

multimodal assembly of cylinders, tubes or bundles of cylinders which are interconnected by a manifold

and assembled within a framework, including service equipment and structural equipment necessary

for the transport of gases

Note 1 to entry: This definition is taken from the UN Model Regulations. ADR uses a different definition.

3.1.1.12
battery vehicle

vehicle containing elements which are linked to each other by a manifold and permanently fixed to a

transport unit

Note 1 to entry: The following elements are considered to be elements of a battery-vehicle: cylinders, tubes,

bundles of cylinders and pressure drums, as well as certain tanks destined for the carriage of gases with a

capacity of more than 450 l.

Note 2 to entry: This term is used in the ADR only. There is no definition in the UN Model Regulations.

3.1.1.13
tank

portable tank, including a tank container, a road tank­vehicle, a rail tank­wagon or a receptacle to

contain solids, liquids or gases, having a capacity of not less than 450 l when used for the transport of

gases

Note 1 to entry: This definition is taken from the UN Model Regulations. ADR uses a different definition.

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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.1.1.14
portable
capable of being carried by hand
Note 1 to entry: When used in connection with tanks, this means “transportable”.
3.1.2 All gas cylinders
3.1.2.1
composite cylinder
cylinder reinforced by continuous filaments held in a matrix
3.1.2.2
acetylene cylinder

cylinder manufactured and suitable for the transport of acetylene, containing a porous material and

solvent (where applicable) for acetylene with a valve and other accessories affixed to the cylinder

3.1.2.3
cylinder end
cylinder base or cylinder shoulder
3.1.3 Composite gas cylinders
3.1.3.1
composite overwrap
combination of fibres (including steel wire) and matrix
3.1.3.2
matrix
material that is used to bind and hold the fibres in place
3.1.3.3
liner

inner portion of a composite cylinder, comprising a metallic or non-metallic vessel, whose purpose is

both to contain the gas and transmit the gas pressure to the composite overwrap
3.1.4 Acetylene cylinders
3.1.4.1
porous material

single- or multiple-component material introduced to, or formed in, the cylinder shell, that, due to its

porosity, allows the absorption of a solvent/acetylene solution
Note 1 to entry: The porous material may be either:

— monolithic, consisting of a solid product obtained by reacting materials or by materials connected together

with a binder; or

— non-monolithic, consisting of granular, fibrous or similar materials without the addition of a binder.

3.1.4.2
top clearance

gap between the inside of the cylinder shoulder and the monolithic porous material

3.1.4.3
solvent

liquid that is absorbed by the porous material and is capable of dissolving and releasing acetylene

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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.1.4.4
specified solvent content

weight of solvent that the acetylene cylinder shall contain and that is established during prototype

testing
3.1.4.5
maximum acetylene content

specified maximum weight of acetylene including saturation acetylene in an

acetylene cylinder
3.1.4.6
maximum acetylene content

specified maximum weight of acetylene including saturation acetylene in

the bundle cylinder
3.1.4.7
maximum acetylene charge
maximum acetylene content minus the saturation acetylene
3.1.4.8
residual gas
residual acetylene

weight of acetylene including the saturation acetylene contained in an acetylene cylinder returned for

filling
3.1.4.9
saturation acetylene
saturation gas

acetylene that remains dissolved in the solvent in the acetylene cylinder at atmospheric pressure

(1,013 bar) and at a temperature of 15 °C
3.1.4.10
tare A

sum of weights of the empty cylinder shell, the porous material, the specified solvent content, the valve,

the coating and the valve guard, where applicable, and all other parts that are permanently attached to

the acetylene cylinder when it is presented to be filled
3.1.4.11
tare S
tare A plus the weight of the saturation acetylene
3.1.4.12
tare F
tare A minus the specified solvent content
3.1.5 Bundles of cylinders, battery vehicles and MEGC
3.1.5.1
frame

structural and non­structural members of a bundle which combine all other components together,

while providing protection for the bundle’s cylinders, valves and manifold, and which enable the bundle

to be transported
EXAMPLE
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.1.5.2
manifold

piping system for connecting pressure receptacle(s) valves or fittings to the main valve(s) or the main

connection(s)
EXAMPLE
3.1.5.3
main connection
means of making a gas connection to a bundle/battery vehicle/MEGC
3.1.5.4
main valve
main shut­off valve
DEPRECATED: bundle valve

valve which is fitted to the manifold of a bundle, battery vehicle, battery wagon or MEGC isolating it

from the main connection(s)
3.2 Terms related to accessories
3.2.1
accessory

generic term for a device fitted to a pressure receptacle needed for operation and/or transport

EXAMPLE Cylinder valve, valve protection cap/valve guard, fitting, pressure regulator, pressure gauge.

3.2.2
fitting
connecting piece of one or more parts having no shut­off function
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.2.3
valve operating mechanism

mechanism which closes and opens the valve orifice and which includes the internal and external

sealing systems

EXAMPLE A threaded valve spindle which, when rotated, raises and lowers a seal/seat.

3.2.4
valve operating device
component which actuates the valve operating mechanism
EXAMPLE Handwheel, key, knob, toggle, lever or actuator.
3.2.5
non-return valve
automatic valve which allows gas to flow only in one direction
EXAMPLE
3.2.6
residual pressure valve
RPV
cylinder valve which incorporates a residual pressure device
3.2.7
residual pressure device
RPD

device that prevents ingress of contaminants by maintaining a positive differential pressure between

the pressure within the cylinder and the valve outlet
3.2.8
excess flow device

device designed to close or partially close when the flow of liquid or vapour passing through it exceeds a

predetermined value and to re­open when the pressure differential across the device has been restored

below a certain value
EXAMPLE
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.2.9
pressure relief device
PRD

collective term which includes bursting disk, fusible plug and pressure relief valve for protecting the

pressure receptacle against overpressurization
3.2.10
pressure relief valve
DEPRECATED: safety valve

pressure actuated valve held shut by a spring or other means and designed to relieve excessive pressure

automatically by starting to open at a set pressure and re-closing after the pressure has fallen below

the set pressure
EXAMPLE
3.2.11
valve protection cap

device securely fixed over the valve during handling, transport and storage and which is removed for

access to the valve
EXAMPLE
3.2.12
valve guard

device securely fixed over the valve during handling, transport and storage and which does not need to

be removed for access to the valve
EXAMPLE
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.2.13
valve shroud

integral part of a welded cylinder or pressure drum for valve protection during transport, handling and

storage
EXAMPLE
3.2.14
dust cap

device which is intended to protect the external inlet or outlet connection of a pressure receptacle valve

against the ingress of dust, dirt or other contamination
EXAMPLE
3.2.15
dust plug

device which is intended to protect the internal inlet or outlet connection of a pressure receptacle valve

against the ingress of dust, dirt or other contamination
3.2.16
sealing cap

device which is intended to seal the external outlet connection of a pressure receptacle valve

EXAMPLE
3.2.17
sealing plug

device which is intended to seal the internal outlet connection of a pressure receptacle valve

EXAMPLE
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oSIST prEN ISO 10286:2021
ISO/FDIS 10286:2021(E)
3.2.18
periodic inspection date ring
DEPRECATED: test date ring
ring indicating the year of the next periodic inspection
EXAMPLE
3.2.19
risk label

label giving information on the primary and subsidiary risks of the content given by a square set at an

angle of 45° (diamond­shaped)
3.2.20
precautionary label

label giving information on the recommended measures to minimize or prevent adverse effects

resulting from exposure to the content, which includes the UN no. and the risk label

EXAMPLE
3.3 Terms related to manufacture
3.3.1
procedure
series of actions conducted in a certain order or manner
3.3.2
method
element of a procedure
3.3.3
workmanship
quality of manufacturing
3.3.4
autofrettage

pressure application procedure which strains the metal liner past its yield strength sufficient to cause

permanent plastic deformation, and results in the liner having compressive stresses and the fibres

having tensile stresses when at zero internal gauge pressure
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oSIST prEN ISO 10286:2021
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3.4 Terms related to testing and inspection
3.4.1
testing
carrying out one or more test(s)
3.4.2
test

technical operation(s) for determining one or more characteristics according to a specified procedure

to identify differences between specified, expected and actual results
3.4.3
inspection

evaluation of conformity by observation and judgement accompanied as appropriate by measurement,

examination, testing or gauging
3.4.4
verification
DEPRECATED: check

confirmation, by examination of objective evidence, that specified requirements have been fulfilled

3.4.5
examination
process having the object of determining a condition by judgement

Note 1 to entry: The examination results in a pass or fail or further measurement, testing or gauging.

3.4.6
maintenance
refurbishment
DEPRECATED: reconditioning

set of activities performed during the operating life of pressure equipment to ensure it complies with

the relevant specification

Note 1 to entry: Maintenance can include cleaning and replacing worn or damaged parts meeting the original

specification.
3.4.7
periodic inspection and maintenance
planned inspection and maintenance task carried out at specified intervals

Note 1 to entry: This term is mainly used for acetylene and sub-atmospheric cylinders.

3.4.8
repair

set of activities performed on defective pressure equipment to restore its compliance with the relevant

specification

Note 1 to entry: Repair can include replacing worn or damaged parts meeting the original specification.

3.4.9
certificate

document that records the conformity of pressure equipment with specified requirements

Note 1 to entry: Certificates can also apply to processes, systems, persons or organizations.

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oSIST prEN ISO 10286:2021
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3.4.10
competent authority

any body or authority designated or otherwise recognized as such for any purpose in each country by

its government

Note 1 to entry: The term “competent body” is not to be used. UN Model recommendations only use “competent

authority” and “inspection body”.
3.4.11
inspection body
independent inspection and testing body approved by the competent authority
Note 1 to entry: This note only applies to the German language.
3.4.12
competent person
DEPRECATED: authorized person

person who is qualified, trained, experienced and approved to perform specified activities such as

periodic inspection and test, welding, etc.
3.4.13
inspector

person who is qualified, trained, experienced and authorized to perform inspection and testing

3.4.14
burst pressure ratio
ratio of burst pressure to test pressure

Note 1 to entry: Sometimes it is used as ratio of burst pressure to working pressure.

3.4.15
leak

loss of fluid across the valve seat (internal leak) or to atmosphere (external leak)

3.4.16
bursting
burst
structural failure of an object due to pressure with extended propagation

Note 1 to entry: For a pressure receptacle, the two failure modes are leak or burst.

Note 2 to entry: In the past, the term “rupture” was sometimes used.
3.4.17
imperfection
any departure of a quality characteristic from its intended level or state

Note 1 to entry: The existence of an imperfection does not necessarily imply nonconformity with the specification,

nor does it have necessarily any implication as to the usability of a product. An imperfection should be rated on

a scale of severity, in accordance with appropriate specifications, to establish whether or not the product is of

acceptable quality.
3.4.18
defect
DEPRECATED: fault

imperfection of sufficient magnitude to warrant rejection of the product based on specified criteria

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ISO/FDIS 10286:2021(E)
3.4.19
flaw
imperfection or defect in the structure of a material

Note 1 to entry: In many standards, the term is used for a machined notch introduced for calibration or testing

purposes.
3.4.20
bulge
visible swelling of the wall
3.4.21
dent
flat
visible depression in the wall that has neither penetrated nor removed metal
3.4.22
cut
gouge
groove
metallic impression
scale impression
impression in the wall where metal has been removed, displaced or redistributed
Note 1 to entry: The appropriate term shall be chosen depending on the context.
3.4.23
blister
small bulge on the wall containing a c
...