EN ISO 10524-1:2006

SLOVENSKI STANDARD
01-april-2006
1DGRPHãþD
OSIST prEN ISO 10524-1:2004
SIST EN 738-1:2000
SIST EN 738-1:2000/A1:2002
SIST EN 738-4:2000
SIST EN 738-4:2000/A1:2002
7ODþQLUHJXODWRUML]DPHGLFLQVNHSOLQH±GHO7ODþQLUHJXODWRUMLLQWODþQLUHJXODWRUML
VSUHWRþQLPLPHULOQLNL,62
Pressure regulators for use with medical gases - Part 1: Pressure regulators and
pressure regulators with flow-metering devices (ISO 10524-1:2006)
Druckminderer zur Verwendung mit medizinischen Gasen - Teil 1: Druckminderer und
Druckminderer mit Durchflussmessgeräten (ISO 10524-1:2006)
Détendeurs pour l'utilisation avec les gaz médicaux - Partie 1: Détendeurs et détendeurs
-débimetres (ISO 10524-1:2006)
Ta slovenski standard je istoveten z: EN ISO 10524-1:2006
ICS:
11.040.10 Anestezijska, respiratorna in Anaesthetic, respiratory and
reanimacijska oprema reanimation equipment
23.060.40 7ODþQLUHJXODWRUML Pressure regulators
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN ISO 10524-1
NORME EUROPÉENNE
EUROPÄISCHE NORM
February 2006
ICS 11.040.10 Supersedes EN 738-1:1997
English Version
Pressure regulators for use with medical gases - Part 1:
Pressure regulators and pressure regulators with flow-metering
devices (ISO 10524-1:2006)
Détendeurs pour l'utilisation avec les gaz médicaux - Partie Druckminderer zur Verwendung mit medizinischen Gasen -
1: Détendeurs et détendeurs à débitmètre intégré (ISO Teil 1: Druckminderer und Druckminderer mit
10524-1:2006) Durchflussmessgeräten (ISO 10524-1:2006)
This European Standard was approved by CEN on 30 November 2005.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2006 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 10524-1:2006: E
worldwide for CEN national Members.

Foreword
This document (EN ISO 10524-1:2006) has been prepared by Technical Committee ISO/TC 121
"Anaesthetic and respiratory equipment" in collaboration with Technical Committee CEN/TC 215
"Respiratory and anaesthetic equipment", the secretariat of which is held by BSI.

This European Standard shall be given the status of a national standard, either by publication of
an identical text or by endorsement, at the latest by August 2006, and conflicting national
standards shall be withdrawn at the latest by August 2006.

This document supersedes EN 738-1:1997.

This document has been prepared under a mandate given to CEN by the European Commission
and the European Free Trade Association, and supports essential requirements of EU
Directive(s).
For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this
document.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of
the following countries are bound to implement this European Standard: Austria, Belgium,
Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

Endorsement notice
The text of ISO 10524-1:2006 has been approved by CEN as EN ISO 10524-1:2006 without any
modifications.
ANNEX ZA
(informative)
Relationship between this European Standard and the Essential
Requirements of EU Directive 93/42 EEC concerning Medical
Devices
This International Standard has been prepared under a mandate given to CEN by the European

Commission and the European Free Trade Association to provide one means of conforming to
Essential Requirements of the New Approach Directive 93/42 EEC Medical Devices.

Once this standard is cited in the Official Journal of the European Communities under that
Directive and has been implemented as a national standard in at least one Member State,
compliance with the normative clauses of this standard given in Table ZA.1 confers, within the
limits of the scope of this standard, a presumption of conformity with the corresponding Essential
Requirements of that Directive and associated EFTA regulations.

Table ZA.1 — Correspondence between this International Standard and Directive
93/42/EEC
Clause(s)/sub-clause(s) of this Essential requirements (ERs) of EU
Qualifying
International standard
Directive 93/42/EEC
remarks/Notes
5 1
5.1 2, 6
5.2 2
5.3 2
5.3.1 7.1, 7.3, 7.9
5.3.2 4, 7.1, 9.2
5.3.3 3, 5
5.3.4 7.1, 7.2
5.4 2, 3, 4
5.4.1.1 10
5.4.1.3 10.2
5.4.1.4 10.1
5.4.2 9.1, 12.7.4
5.4.3 3, 9.1, 12.7.4
5.4.4 12.3
5.4.5 12.8
5.4.6 12.7.1, 12.8.1
5.4.7 7.2, 7.6, 9.3
5.4.8 7.5, 9.2, 12.7.1
5.4.9 7.5
5.4.10 9.2, 12.7.1
5.4.11 7.3, 9.3
5.4.12.1 10.3, 12.8.2
5.4.12.2 10.2
5.4.12.3 10.1, 12.8.1, 12.8.2
5.4.12.4 10.1, 12.8.1, 12.8.2
5.4.13.1 10.3, 12.8.1, 12.8.2
5.4.13.2 10.1, 12.8.1, 12.8.2
5.4.13.3 10.1, 12.8.1, 12.8.2
5.4.14.1 10.1, 12.8.1, 12.8.2
5.4.14.2 12.8.1, 12.8.2
5.4.14.3 12.8.1, 12.8.2
5.4.14.4 10.2
5.5.1 7.2, 9.3
5.5.2 7.1, 9.3
6 3, 7.5, 9.2, 9.3, 12.8.1, 12.8.2
7.1 13, 13.2
7.1.2 a) 13.1, 13.3 a)
7.1.2 b) 13.3 b)
7.1.2 c) 13.3 d), 13.5
7.1.4 a) 13.1, 13.3 a)
7.1.5 12.9
7.2 13.2
7.3 3, 5
7.3.1 5, 7.2, 7.6
7.3.2 13, 13.3 b)
8.1 13.1, 13.3 a), 13.4, 13.6 a)
8.2 13.6 b)
8.3 13.6 b)
8.4 9.1, 9.2, 9.3, 13.1, 13.6 c), 13.6 d)

WARNING: Other requirements and other EU Directives may be applicable to the products
falling within the scope of this standard.

INTERNATIONAL ISO
STANDARD 10524-1
First edition
2006-02-01
Pressure regulators for use with medical
gases —
Part 1:
Pressure regulators and pressure
regulators with flow-metering devices
Détendeurs pour l'utilisation avec les gaz médicaux —
Partie 1: Détendeurs et détendeurs à débitmètre intégré

Reference number
ISO 10524-1:2006(E)
©
ISO 2006
ISO 10524-1:2006(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.

©  ISO 2006
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 2
3 Terms and definitions. 2
4 Nomenclature . 4
5 General requirements. 4
5.1 Safety . 4
5.2 Alternative construction . 4
5.3 Materials . 4
5.4 Design requirements . 5
5.5 Constructional requirements. 12
6 Test methods. 12
6.1 General. 12
6.2 Test methods for outlet pressure. 13
6.3 Test method for pressure-relief valve. 14
6.4 Test methods for leakage . 14
6.5 Test method for mechanical strength. 15
6.6 Test method for resistance to ignition . 15
6.7 Test method for accuracy of flow of pressure regulators fitted with flowmeters or
flowgauges . 16
6.8 Test method for the stability of flow of pressure regulators fitted with flowmeters or
flowgauges . 16
6.9 Test method for stability and accuracy of flow of pressure regulators fitted with fixed
orifices . 16
6.10 Test method for flow setting and loosening torques. 16
6.11 Test method for durability of markings and colour coding. 16
7 Marking, colour coding, packaging . 16
7.1 Marking . 16
7.2 Colour coding. 18
7.3 Packaging . 18
8 Information to be supplied by the manufacturer. 18
Annex A (informative) Typical examples of pressure regulators and pressure regulators with flow-
metering devices. 22
Annex B (informative) Rationale . 26
Annex C (informative) Reported regional and national deviations of colour coding and
nomenclature for medical gases. 28
Bibliography . 30

ISO 10524-1:2006(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 10524-1 was prepared by Technical Committee ISO/TC 121, Anaesthetic and respiratory equipment,
Subcommittee SC 6, Medical gas systems.
This first edition cancels and replaces ISO 10524:1995 and ISO 10524:1995/Cor 1:1996, which has been
technically revised.
ISO 10524 consists of the following parts, under the general title Pressure regulators for use with medical
gases:
⎯ Part 1: Pressure regulators and pressure regulators with flow-metering devices
⎯ Part 2: Manifold and line pressure regulators
⎯ Part 3: Pressure regulators integrated with cylinder valves
⎯ Part 4: Low-pressure regulators
For the purposes of this part of ISO 10524, the CEN annex regarding fulfilment of European Council
Directives has been removed.
iv © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
Introduction
A pressure regulator is used to reduce high cylinder pressure to a lower pressure suitable for use with medical
equipment or for delivery of gas directly to a patient.
These functions cover a wide range of inlet and outlet pressures and flows which require specific design
characteristics. It is important that the operating characteristics of the pressure regulators are specified and
tested in a defined manner.
A pressure regulator often has coupled to it a device which controls the flow, such as a flow control valve or a
fixed orifice. The flow can be indicated by a flowmeter or by a flowgauge.
It is essential that regular inspection and maintenance are undertaken to ensure that pressure regulators
continue to meet the requirements of this part of ISO 10524.
This part of ISO 10524 pays particular attention to:
⎯ use of suitable materials;
⎯ safety (mechanical strength, leakage, safe relief of excess pressure and resistance to ignition);
⎯ gas specificity;
⎯ cleanliness;
⎯ type testing;
⎯ marking;
⎯ information supplied by the manufacturer.
Annex B contains rationale statements for some of the requirements of this part of ISO 10524. The clauses
and subclauses marked with an asterix (*) after their number have corresponding rationale, contained in
Annex B, included to provide additional insight into the reasoning that led to the requirements and
recommendations that have been incorporated in this part of ISO 10524. It is considered that knowledge of
the reasons for the requirements will not only facilitate the proper application of this part of ISO 10524, but will
expedite any subsequent revisions.

INTERNATIONAL STANDARD ISO 10524-1:2006(E)

Pressure regulators for use with medical gases —
Part 1:
Pressure regulators and pressure regulators with flow-metering
devices
1 Scope
1.1 This part of ISO 10524 is applicable to the types of pressure regulators listed in 1.3 intended for the
administration of the following medical gases in the treatment, management, diagnostic evaluation and care of
patients:
⎯ oxygen;
⎯ nitrous oxide;
⎯ air for breathing;
⎯ helium;
⎯ carbon dioxide;
⎯ xenon;
⎯ mixtures of the gases listed above;
⎯ air for driving surgical tools;
⎯ nitrogen for driving surgical tools.
1.2* These pressure regulators are intended to be fitted to cylinders with nominal filling pressures up to
25 000 kPa at 15 °C and can be provided with devices which control and measure the flow of the medical gas
delivered.
1.3 The types of pressure regulators covered by this part of ISO 10524 are as follows:
a) pressure regulators intended to be connected to cylinders by the operator;
b) pressure regulators with integral flow-metering devices intended to be connected to cylinders by the
operator;
c) pressure regulators that are an integral part of medical equipment (e.g. anaesthetic workstations, lung
ventilators, resuscitators).
ISO 10524-1:2006(E)
2 Normative references
The following referenced documents are indispensable for the application 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 32:1977, Gas cylinders for medical use — Marking for identification of content
ISO 407:2004, Small medical gas cylinders — Pin-index, yoke-type valve connections
ISO 5145:2004, Cylinder valve outlets for gases and gas mixtures — Selection and dimensioning
ISO 5359:2000, Low-pressure hose assemblies for use with medical gases
ISO 9170-1:1999, Terminal units for medical gas pipeline systems — Part 1: Terminal units for use with
compressed medical gases and vacuum
ISO 14971:2000, Medical devices — Application of risk management to medical devices
ISO 15001:2003, Anaesthetic and respiratory equipment — Compatibility with oxygen
EN 837-1:1996, Pressure gauges — Part 1: Bourdon tube pressure gauges — Dimensions, metrology,
requirements and testing
EN 13544-2:2002, Respiratory therapy equipment — Part 2: Tubing and connectors
SS 01 91 02, Colour Atlas
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
accuracy of flow
difference between the indicated value and the actual value of the flow expressed in percent
3.2
adjustable pressure regulator
pressure regulator that is provided with a means of operator adjustment of the outlet pressure
3.3
flow outlet
outlet intended to deliver a controlled flow of gas
3.4
flowgauge
device that measures pressure and that is calibrated in units of flow
NOTE The flowgauge does not measure flow. It indicates flow by measuring the pressure upstream of a fixed orifice.
3.5
flowmeter
device that measures and indicates the flow of a specific gas or gas mixture
3.6
gas-specific connection point
that part of the terminal unit that is the receptor for a gas-specific probe
2 © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
3.7
gas-specific
having characteristics that prevent connection between different gas services
3.8
nipple
that portion of a connector that is pushed into and secured within the bore (lumen) of a hose
3.9
nominal inlet pressure
p
upstream pressure specified by the manufacturer for which the pressure regulator is intended to be used
NOTE For compressed gases (e.g. oxygen) p is related to the cylinder filling pressure at 15 °C.
3.10
nominal outlet pressure
p
nominal downstream pressure
NOTE p is specified by the manufacturer in the instructions for use.
3.11
orifice
restriction of known cross-section that delivers a constant flow of gas when supplied with gas at a constant
upstream pressure
NOTE An orifice does not provide an indication of flow.
3.12
preset pressure regulator
pressure regulator that is not provided with a means of operator adjustment of the outlet pressure
3.13
pressure gauge
device that measures and indicates pressure
3.14
pressure outlet
outlet intended to deliver gas at a controlled pressure
3.15
pressure regulator
device that reduces the inlet pressure and maintains the set outlet pressure within specified limits
3.16
pressure-relief valve
device intended to relieve excess pressure at a preset value
3.17
single fault condition
condition in which a single means for protection against a safety hazard in equipment is defective or a single
external abnormal condition is present
[IEC 60601-1]
ISO 10524-1:2006(E)
4 Nomenclature
Examples of pressure regulators with terminology are given in Annex A.
5 General requirements
5.1 Safety
Pressure regulators shall, when transported, stored, installed, operated in normal use and maintained
according to the instructions of the manufacturer, cause no safety hazard which could be foreseen using risk
management procedures in accordance with ISO 14971:2000 and which is connected with their intended
application, in normal condition and in single fault condition.
5.2 Alternative construction
Pressure regulators and components or parts thereof, using materials or having forms of construction different
from those detailed in this clause shall be accepted if it can be demonstrated that an equivalent degree of
safety is obtained.
Such evidence shall be provided by the manufacturer upon request.
NOTE Regional or national regulations can require the provision of evidence to a notified body or competent authority
upon request.
5.3 Materials
5.3.1* The materials in contact with the medical gases listed in 1.1 during normal use shall be resistant to
corrosion and compatible with oxygen, the other medical gases and their mixtures in the temperature range
specified in 5.3.2.
NOTE 1 Corrosion resistance includes resistance against moisture and surrounding materials.
NOTE 2 Oxygen compatibility is usually defined as the ability of a material to coexist with oxygen and a moderate
ignition source. The goal of using oxygen-compatible materials is to develop system designs with low probability of ignition
and low consequence of ignition based on the use of materials exhibiting good compatibility and low energy release if
ignited. Many materials which do not burn in air will do so in pure oxygen, particularly under pressure. Similarly, materials
which can be ignited in air require lower ignition energies for ignition in oxygen. Many such materials can be ignited by
friction at a valve seat or by adiabatic compression produced when oxygen at high pressure is rapidly introduced into a
system initially at low pressure.
NOTE 3 Criteria for the selection of metallic and non-metallic materials are given in ISO 15001:2003.
5.3.2 The materials shall permit the pressure regulator and its components to meet the requirements of 5.4
in the temperature range of −20 °C to +60 °C.
NOTE Regional or national environmental conditions might require deviation from this range of temperatures.
5.3.3 Pressure regulators shall meet the requirements of this part of ISO 10524 after being packed for
transport and storage and being exposed to environmental conditions as stated by the manufacturer.
5.3.4 Springs, highly-strained components and parts liable to wear which come in contact with the medical
gas shall not be plated.
NOTE Plating could come off.
5.3.5* Aluminium or aluminium alloys shall not be used for components whose surfaces come into contact
with gas at cylinder pressure in normal or single-fault condition.
4 © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
5.3.6 Evidence of conformity with the requirements of 5.3.1, 5.3.2, 5.3.3, 5.3.4 and 5.3.5 shall be provided
by the manufacturer upon request.
NOTE Regional or national regulations might require the provision of evidence to a notified body or competent
authority upon request.
5.4 Design requirements
5.4.1 Pressure gauges and flowgauges
5.4.1.1 If a Bourdon tube pressure gauge or flowgauge is used, it shall conform to EN 837-1:1996
(except for the minimum nominal size) and shall meet the requirements in 5.4.1.2, 5.4.1.3, 5.4.1.4, 5.4.1.5 and
5.4.1.6.
The requirements in 5.4.1.2, 5.4.1.3, 5.4.1.4, 5.4.1.5, 5.4.1.6 and 5.4.1.7 also apply to other types of pressure
gauges and flowgauges.
5.4.1.2 If the gauge connector is threaded, it shall comply with EN 837-1:1996 or a regional or national
standard.
5.4.1.3 The indicated value of a pressure gauge or flowgauge shall be legible to an operator having a
visual acuity of 1 (corrected if necessary) 1 m from the gauge with an illuminance of 215 lx.
5.4.1.4 The scale of the cylinder pressure gauge shall extend to a pressure at least 33 % greater than
nominal inlet pressure p .
NOTE In addition to the scale ranges in EN 837-1:1996, a pressure gauge with a scale range of 0 kPa to 31 500 kPa
(315 bar) can also be used.
5.4.1.5 The cylinder pressure gauge, outlet pressure gauge or flowgauge shall be class 2,5 or better in
accordance with EN 837-1:1996.
5.4.1.6 The connector for a pressure gauge with a scale range greater than 4 000 kPa shall be fitted with
an orifice with an area no greater than 0,1 mm .
5.4.1.7 Evidence of conformity with the requirements of 5.4.1.1 and 5.4.1.5 shall be provided by the
manufacturer upon request. Compliance with the requirements of 5.4.1.2, 5.4.1.3, 5.4.1.4 and 5.4.1.6 shall be
checked by visual inspection or measurement as required.
NOTE Regional or national regulations might require the provision of evidence to a notified body or competent
authority upon request.
5.4.2 Connectors
5.4.2.1 Inlet connector
There shall be an inlet connector. The inlet connector for connection to cylinders shall comply with either
ISO 407:1991, ISO 5145:2004 or the relevant regional or national standards. See ISO/TR 7470:1988 for
information.
5.4.2.2 Outlet connector
Except for pressure regulators that are an integral part of medical equipment, the outlet connector(s) shall be
in accordance with 5.4.2.2.1 and/or 5.4.2.2.2.
NOTE A pressure regulator can have multiple outlets and can have both a pressure outlet and a flow outlet.
ISO 10524-1:2006(E)
5.4.2.2.1* Flow outlet
A flow outlet shall be fitted with a fixed nipple or a threaded connector.
Nipples, if used, shall be in accordance with EN 13544-2:2002.
Threaded connectors for oxygen or air for breathing, if used, shall be in accordance with EN 13544-2:2002 or
equivalent regional or national standards or shall be manufacturer-specific connectors. Threaded connectors,
if used for other gases, shall be in accordance with regional or national standards or shall be manufacturer-
specific connectors.
A flow outlet shall not be fitted on a pressure regulator intended for use with air or nitrogen for driving surgical
tools.
5.4.2.2.2 Pressure outlet
A pressure outlet shall be fitted with one of the following:
a) a terminal unit or a gas-specific connection point in accordance with ISO 9170-1:1999, for the following
medical gases:
⎯ oxygen;
⎯ nitrous oxide;
⎯ air for breathing;
⎯ carbon dioxide;
⎯ oxygen/nitrous oxide mixture 50/50 (volume fraction, %);
⎯ air for driving surgical tools;
⎯ nitrogen for driving surgical tools;
⎯ other gases for which terminal units in national standards exist (the connection of the terminal unit or
the gas-specific connection point to the pressure regulator body need not be gas-specific).
b) a NIST or DISS body in accordance with ISO 5359:2000, unless a national standard exists for terminal
units, for the following medical gases:
⎯ helium;
⎯ xenon;
⎯ mixtures of oxygen and nitrous oxide [except 50/50 (volume fraction, %)];
⎯ mixtures of oxygen and helium;
⎯ mixtures of oxygen and carbon dioxide;
c) a connector in accordance with regional or national standards.
6 © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
5.4.3* Outlet pressure
Except for pressure regulators that are an integral part of medical equipment, the pressure requirements for a
pressure outlet are given in 5.4.3.1.1 and 5.4.3.1.2.
The pressure requirement for a flow outlet is given in 5.4.3.2.
5.4.3.1 Pressure outlet
If a pressure regulator is fitted with a pressure outlet, the pressure regulator shall be preset.
5.4.3.1.1 Nominal outlet pressure (p )
Except for pressure regulators that are an integral part of medical equipment, the range of nominal outlet
pressure p shall be:
+100
a) (400 ) kPa for medical gases other than air or nitrogen for driving surgical tools, or
+200
b) (800 ) kPa for air or nitrogen for driving surgical tools.
−100
5.4.3.1.2 Outlet pressure limits
The outlet pressure from a pressure regulator fitted with a pressure outlet (except for air or nitrogen for driving
surgical tools) shall not be less than 360 kPa and not greater than 550 kPa at any flow between 0 l/min and
40 l/min for all inlet pressures between p and 1 000 kPa.
The outlet pressure for a pressure regulator for air or nitrogen for driving surgical tools fitted with a pressure
outlet shall not be less than 595 kPa and not greater than 1 150 kPa at any flow between 0 l/min and 350 l/min
for all inlet pressures between p and 2 000 kPa.
On a pressure regulator fitted with multiple pressure outlets, each pressure outlet shall be capable of meeting
these requirements while all outlets are operating simultaneously.
The test for outlet pressure limits is given in 6.2.2.
5.4.3.2 Flow outlet
The pressure immediately upstream of a flow control device shall not be greater than 550 kPa for inlet
pressures between p and 1 000 kPa for all flow settings including zero flow.
The test for the flow outlet pressure limit is given in 6.2.3.
5.4.4 Cylinder pressure or content indicator
The pressure regulator shall be fitted with, or connected to, a cylinder pressure gauge or with an equivalent
means to indicate the cylinder gas pressure or content.
NOTE In a cylinder with liquefiable gas (e.g. nitrous oxide) the pressure might not indicate the volume of gas in the
cylinder.
ISO 10524-1:2006(E)
5.4.5 Flow-metering device
If the pressure regulator is fitted with a flow outlet(s) in accordance with 5.4.2.2.1 it shall also be fitted with a
flow-metering device.
A typical flow-metering device is one of the following:
a) a flowmeter and a flow control valve supplied by a preset pressure regulator (see 5.4.12);
b) a flowgauge and a fixed orifice supplied by an adjustable pressure regulator (see 5.4.13);
c) multiple fixed orifices, with a means of selecting an orifice, supplied by a preset pressure regulator
(see 5.4.14).
5.4.6 Pressure-adjusting device
5.4.6.1 If a pressure-adjusting device is fitted, it shall be captive such that it cannot be disengaged
without the use of a tool.
Compliance shall be tested by attempting to remove the pressure-adjusting device without the use of a tool.
5.4.6.2 The pressure regulator shall be designed so that the pressure regulator valve cannot be held in
the open position as a consequence of the pressure regulator spring being compressed to its solid length.
Compliance shall be verified by functional testing
5.4.6.3 Using the pressure-adjusting device it shall not be possible to set a pressure at which the
pressure-relief valve opens.
Compliance shall be verified by functional testing.
5.4.7* Filtration
The pressure regulator shall be fitted on the inlet side with a filter that prevents particles greater than 100 µm
from entering the pressure regulator.
NOTE 1 The selection of the material of the filter is particularly important to reduce the probability of ignition.
See ISO 15001:2003 for guidance.
Evidence of conformity shall be provided by the manufacturer upon request.
NOTE 2 Regional or national regulations may require the provision of evidence to a notified body or competent
authority upon request.
5.4.8* Pressure-relief valve
A pressure-relief valve shall be provided as a component part of the pressure regulator. The pressure-relief
valve shall be either:
⎯ preset; or
⎯ not adjustable without the use of a special tool.
The leakage from the pressure-relief valve shall comply with the requirement of 5.4.9.1 up to a pressure of
550 kPa for compressed medical gases (except for air or nitrogen for driving surgical tools) and 1 150 kPa for
air or nitrogen for driving surgical tools.
8 © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
The pressure-relief valve shall lift automatically to relieve excess pressure and shall reset at a pressure equal
to or above 550 kPa for compressed medical gases (except for air or nitrogen for driving surgical tools) and
1 150 kPa for air or nitrogen for driving surgical tools.
The discharge from the pressure-relief valve shall be equal to or greater than the maximum predicted flow
through the pressure regulator valve in single fault condition at an outlet pressure of 1 000 kPa for
compressed medical gases (except for air or nitrogen for driving surgical tools) and 2 000 kPa for air or
nitrogen for driving surgical tools.
The pressure-relief valve shall be fitted in such a way that gas will be discharged safely.
NOTE 1 For guidance on safety, see ISO 14971:2000.
The maximum predicted flow through the pressure regulator valve in single fault condition shall be determined
by the manufacturer and made available upon request.
NOTE 2 Possible single fault conditions that could result in maximum predicted flow include damage to, or loss of, the
valve soft seat material.
NOTE 3 The performance characteristics of the pressure-relief valve on pressure regulators that are an integral part of
medical equipment are at the discretion of the medical equipment manufacturer.
The test for the pressure-relief valve is given in 6.3.
5.4.9 Leakage
5.4.9.1 The total external leakage to atmosphere shall not exceed 0,2 ml/min (equivalent to a pressure
decay of 0,020 2 kPa⋅l/min).
The test for total external leakage is given in 6.4.1.
5.4.9.2 The internal leakage through the pressure regulator valve shall not exceed 0,2 ml/min (equivalent
to a pressure decay of 0,020 2 kPa⋅l/min).
The test for internal leakage is given in 6.4.2.
5.4.10 Mechanical strength
5.4.10.1 The high-pressure side of the pressure regulator shall be capable of withstanding 2,25 × its
nominal inlet pressure (p ) for 5 min without rupturing.
The test is given in 6.5.1.
5.4.10.2 The low-pressure side of the pressure regulator including any integral flow control device (except
for air or nitrogen for driving surgical tools) shall be capable of withstanding a pressure of 2 200 kPa for 5 min
without rupturing.
The test is given in 6.5.2.1.
NOTE 2 200 kPa is 4 × the maximum permissible outlet pressure of 550 kPa (see 5.4.3.1.2).
5.4.10.3 The low-pressure side of the pressure regulator for air or nitrogen for driving surgical tools, shall
be capable of withstanding a pressure of 4 600 kPa for 5 min without rupturing.
The test is given in 6.5.2.1.
NOTE 4 600 kPa is 4 × the maximum permissible outlet pressure of 1 150 kPa (see 5.4.3.1.2).
ISO 10524-1:2006(E)
5.4.10.4 Components of the pressure regulator shall not be ejected if the low-pressure chamber of the
pressure regulator is exposed to nominal inlet pressure (p ) (e.g. if the regulator valve is held in the open
position and the outlet connector is closed). The high-pressure gas shall either be safely retained or vented.
The test is given in 6.5.2.2.
5.4.11* Resistance to ignition
Pressure regulators for all medical gases shall not ignite or show internal scorching when subjected to oxygen
pressure shocks.
The tests for resistance to ignition are given in 6.6.
5.4.12 Requirements for pressure regulators with integral flowmeters
5.4.12.1 Scales and indicators of flowmeters
Flowmeters shall be graduated in units of litres per minute (l/min) or for flows equal to or less than 1 l/min in
units of millilitres per minute (ml/min).
Compliance shall be checked by visual inspection.
5.4.12.2 Legibility
The indicated value of the flowmeter shall be legible to an operator having visual acuity of 1 (corrected if
necessary), 1 m from the flowmeter with an illuminance of 215 lx.
5.4.12.3 Accuracy of flow
The accuracy of the flow at any graduation of a flowmeter shall be within ± 10 % of the indicated value for
flows between 10 % and 100 % of full scale or ± 0,5 l/min, whichever is greater, when the flow is discharged
into ambient atmosphere and corrected to reference conditions (see 6.1.3).
The accuracy of the flow at any flow graduation of a flowmeter with a maximum flow of 1 l/min or less shall be
within ± 10 % of full scale.
The test for accuracy of flow is given in 6.7.
To enhance accuracy and to reduce the hazard of electrostatic discharge, means should be provided to
minimize the build-up of electrostatic charges both inside and outside the flowmeter tube and its housing.
5.4.12.4 Stability of flow
The actual flow, at the maximum flow specified by the manufacturer, shall not vary by more than ± 20 % with
to 1 000 kPa.
the inlet pressure decreasing from p
The test for stability of flow is given in 6.8.
5.4.12.5 Flow control valve
5.4.12.5.1 If a flow control valve is fitted, the flow control knob and the valve spindle shall be captive such
that they cannot be disengaged without the use of a tool.
Compliance shall be tested by attempting to remove the knob and spindle without the use of a tool.
5.4.12.5.2 The flow control valve shall be designed so that the flow increases when the knob is turned
anticlockwise.
Compliance shall be checked by visual inspection.
10 © ISO 2006 – All rights reserved

ISO 10524-1:2006(E)
5.4.13 Requirements for pressure regulators fitted with flowgauges
5.4.13.1 Calibration
The flowgauge shall be calibrated for the identified fixed orifice and graduated in units of litres per
minute (l/min).
5.4.13.2 Accuracy of flow
The accuracy of the flow at any graduation of a flowgauge shall be within ± 10 % of the indicated value for
flows between 10 % and 100 % of full scale or ± 0,5 l/min, whichever is greater, when the flow is discharged
into ambient atmosphere and corrected to reference conditions (see 6.1.3).
The test for accuracy of flow is given in 6.7.
5.4.13.3 Stability of flow
The actual flow, at the maximum flow specified by the manufacturer, shall not vary by more than ± 20 % with
the inlet pressure decreasing from p to 1 000 kPa.
The test for stability of flow is given in 6.8.
5.4.14 Requirements for pressure regulators fitted with fixed orifices
5.4.14.1 Stability and accuracy of flow
The actual flow shall be within ± 20 % of each stated value or ± 30 % of each stated value for flows of
1,5 l/min or less with the inlet pressure decreasing from p to 1 000 kPa.
The test for stability and accuracy of flow is given in 6.9.
5.4.14.2* Flow setting torque
If there are multiple orifices, the tangential force required at the maximum radius of the flow-selecting device
to change from the “off” position and from one setting to another shall be not less than 5 N and not more than
50 N.
The test for flow setting torque is given in 6.10.
It is recommended that the flow-selecting device be designed to self-centre on a flow setting and to minimise
the likelihood of selection of positions of no flow (e.g. between adjacent settings) except for the zero flow
setting.
5.4.14.3 Removal of a fixed orifice
Removal of a fixed orifice shall require the use of a tool.
Compliance shall be tested by attempting to remove a fixed orifice without the use of a tool.
5.4.14.4 Legibility
The set value of the fixed orifice in use shall be legible to an operator having visual acuity of 1 (corrected if
necessary), 1 m from the pressure regulator with an illuminance of 215 lx.
ISO 10524-1:2006(E)
5.5 Constructional requirements
5.5.1* Cleanliness
Components in contact with the medical gases during normal use of pressure regulators for all gases shall
meet the cleanliness requirements of ISO 15001:2003.
Evidence of conformity with this requirement shall be provided by the manufacturer upon request.
NOTE Regional or national regulations might require the provision of evidence to a notified body or competent
authority upon request.
5.5.2 Lubricants
If lubricants are used, they shall be compatible with oxygen, the other medical gases listed in 1.1 and their
mixtures in the temperature range specified in 5.3.2. Evidenc
...