ISO 7396-1:2002

INTERNATIONAL ISO
STANDARD 7396-1
First edition
2002-09-01


Medical gas pipeline systems —
Part 1:
Pipelines for compressed medical gases
and vacuum
Réseaux de distribution de gaz médicaux —
Partie 1: Réseaux de distribution de gaz médicaux comprimés et de vide




Reference number
ISO 7396-1:2002(E)
©
 ISO 2002

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ISO 7396-1:2002(E)
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ISO 7396-1:2002(E)
Contents Page
Foreword . v
Introduction. vi
1 Scope. 1
2 Normative references. 2
3 Terms and definitions. 2
4 General requirements . 6
4.1 Safety. 6
4.2 Alternative construction. 6
4.3 Materials. 6
4.4 System design . 7
5 Supply systems . 8
5.1 System components. 8
5.2 General requirements . 8
5.3 Supply system with cylinders. 9
5.4 Supply systems with mobile or stationary cryogenic vessels. 10
5.5 Supply systems for air. 10
5.6 Supply systems for oxygen-enriched air. 14
5.7 Supply systems for vacuum . 14
5.8 Location of cylinder manifolds . 15
5.9 Location of stationary cryogenic vessels. 15
5.10 Location or vacuum pumps and air compressor systems . 15
5.11 General requirements for supply systems . 15
6 Monitoring and alarm systems . 15
6.1 General . 15
6.2 Installation requirements. 15
6.3 Monitoring and alarm signals . 16
6.4 Provision of operating alarms . 17
6.5 Provision of emergency clinical alarms. 18
6.6 Provision of emergency operating alarms . 18
7 Pipeline distribution systems . 18
7.1 Mechanical resistance . 18
7.2 Distribution pressure. 19
7.3 Low-pressure hose assemblies and flexible connections. 20
7.4 Double-stage pipeline distribution system. 20
8 Shut-off valves. 20
8.1 General . 20
8.2 Service shut-off valves . 21
8.3 Area shut-off valves. 21
9 Terminal units, gas-specific connectors, medical supply units, pressure regulators and
pressure gauges. 22
10 Marking and colour coding . 23
10.1 Marking. 23
10.2 Colour coding . 23
11 Pipeline installation. 23
11.1 General . 23
11.2 Pipeline supports . 24
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ISO 7396-1:2002(E)
11.3 Pipeline joints . 25
11.4 Extensions and modifications of existing medical gas pipeline systems . 25
11.5 Interconnection of pipelines . 25
12 Testing, commissioning and certification . 25
12.1 General . 25
12.2 General requirements for tests. 26
12.3 Tests and inspections after installation of pipeline distribution systems with at least the base
blocks of all terminal units fitted but before concealment . 26
12.4 Tests and procedures after complete installation and before use of the system . 26
12.5 Requirements for tests and inspections after installation of pipeline distribution systems with
at least the base blocks of all terminal units fitted but before concealment (see 12.2). 27
12.6 Requirements for tests and procedures after complete installation and before use of the
system (see 12.3). 28
12.7 Certification of the systems . 31
13 Information to be supplied by the manufacturer . 32
13.1 Instruction manuals . 32
13.2 Maintenance schedules . 32
13.3 “As-installed” drawings. 32
13.4 Electrical diagrams. 32
Annex A (informative) Schematic representation of supply systems . 33
Annex B (informative) Guidelines for location of cylinder manifolds and stationary vessels for
cryogenic or non-cryogenic liquids . 59
Annex C (informative) General guidelines for supply systems . 60
Annex D (informative) Guidelines for emergency procedures. 62
Annex E (informative) Example of procedure for testing and commissioning . 64
Annex F (informative) Temperature and pressure relationships . 75
Annex G (informative) Determination of total leakage from terminal units . 77
Annex H (informative) Typical forms for certification of the medical gas pipeline system . 78
Annex I (informative) Recommended procedures for organization of maintenance. 99
Annex J (informative) Procedure for measuring pipeline volume . 101
Annex K (informative) Rationale. 102
Bibliography. 104

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ISO 7396-1:2002(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 3.
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 part of ISO 7396 may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 7396-1 was prepared by Technical Committee ISO/TC 121, Anaesthetic and respiratory equipment,
Subcommittee SC 6, Medical gas systems.
This first edition of ISO 7396-1 cancels and replaces (with ISO 7396-2) the first edition of ISO 7396
(ISO 7396:1987), which has been technically revised.
ISO 7396 consists of the following parts, under the general title Medical gas pipeline systems:
 Part 1: Pipelines for compressed medical gases and vaccum
 Part 2: Anaesthetic gas scavenging disposal systems
Annexes A, B, C, D, E, F, G, H, I, J and K of this part of ISO 7396 are for information only.
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ISO 7396-1:2002(E)
Introduction
Many health care facilities use pipeline systems to deliver medical gases and vacuum to areas where they are
used in patient care or to power equipment such as ventilators and surgical tools.
This part of ISO 7396 specifies requirements for pipeline systems for compressed medical gases and vacuum. It is
intended for use by those persons involved in the design, construction, inspection and operation of health care
facilities treating human beings. Those persons involved in the design, manufacture and testing of equipment
intended to be connected to pipeline systems should also be aware of the contents of this document.
This part of ISO 7396 seeks to ensure that medical gas pipelines contain only the specific gas intended to be
supplied. For this reason gas-specific components are used for terminal units and for other connectors which are
intended to be used by the operator. In addition, each system is tested and certified to contain only the specific
gas.
The objectives of this part of ISO 7396 are to ensure the following:
a) non-interchangeability between different systems by design;
b) continuous supply of gases and vacuum by providing appropriate sources;
c) use of suitable materials;
d) cleanliness of components;
e) correct installation;
f) provision of monitoring and alarm systems;
g) correct marking of the pipeline system;
h) testing, commissioning and certification;
i) purity of the gases delivered by the system.
Annex K contains rationale statements for some of the requirements of this part of ISO 7396. It is included to
provide additional insight into the reasoning that led to the requirements and recommendations that have been
incorporated in this part of ISO 7396. The clauses and subclauses marked with R after their number have
corresponding rationale contained in annex K.
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INTERNATIONAL STANDARD ISO 7396-1:2002(E)

Medical gas pipeline systems —
Part 1:
Pipelines for compressed medical gases and vacuum
1 Scope
This part of ISO 7396 specifies requirements for design, installation, function, performance, documentation, testing
and commissioning of compressed medical gas and vacuum pipeline systems in health care facilities to ensure
continuous delivery of the correct gas from the pipeline system. It includes requirements for supply systems,
pipeline distribution systems, control systems, monitoring and alarm systems and non-interchangeability between
components of different gas systems.
This part of ISO 7396 is applicable to pipeline systems for the following medical gases:
 oxygen;
 oxygen-enriched air;
 nitrous oxide;
 air for breathing;
 carbon dioxide;
 oxygen/nitrous oxide mixtures;
 air for driving surgical tools;
 nitrogen for driving surgical tools;
and to vacuum pipeline systems.
R This part of ISO 7396 is also applicable to pipeline distribution systems for oxygen-enriched air connected to
supply systems with oxygen concentrators complying with ISO 10083.
This part of ISO 7396 also applies to extensions and modifications of existing pipeline systems.
This part of ISO 7396 is not applicable to provision for gas-specific connectors on mobile or stationary cryogenic
vessels or on transport vehicles, or on the inlet/outlet of cylinders for non-cryogenic liquid or gas.
This part of ISO 7396 does not apply to medical gas pipeline systems supplying hyperbaric chambers.
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ISO 7396-1:2002(E)
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 7396. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 7396 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
ISO 407, Small medical gas cylinders — Pin-index yoke-type valve connections
ISO 3746, Acoustics — Determination of sound power levels of noise sources using sound pressure — Survey
method using an enveloping measurement surface over a reflecting plane
ISO 4135, Anaesthesitic and respiratory equipment — Vocabulary
ISO 5145, Cylinder valve outlets for gases and gas mixtures — Selection and dimensioning
ISO 5359, Low-pressure hose assemblies for use with medical gases
ISO/TR 7470, Valve outlets for gas cylinders — List of provisions which are either standardized or in use
ISO 9170-1, Terminal units for medical gas pipeline systems — Part 1: Terminal units for use with compressed
medical gases and vacuum
ISO 9703-1, Anaesthesia and respiratory care alarm signals — Part 1: Visual alarm signals
ISO 9703-2, Anaesthesia and respiratory care alarm signals — Part 2: Auditory alarm signals
ISO 10083:1992, Oxygen concentrators for use with medical gas pipeline systems
ISO 10524:1995, Pressure regulators and pressure regulators with flow-metering devices for medical gas systems
ISO 10524-2, Pressure regulators for use with medical gases — Part 2: Manifold and line pressure regulators
ISO 11197, Medical electrical equipment — Particular requirements for safety of medical supply units
ISO 14971, Medical devices — Application of risk management to medical devices
ISO 15001, Anaesthetic and respiratory equipment — Compatibility with oxygen
EN 143:1990, Respiratory protective devices — Particle filters — Requirements, testing, marking
EN 286-1:1998, Simple unfired pressure vessels designed to contain air or nitrogen — Part 1: Pressure vessels for
general purposes
EN 13348:2001, Copper and copper alloys — Seamless round copper tubes for medical gases or vacuum
3 Terms and definitions
For the purposes of this part of ISO 7396, the following terms and definitions apply.
3.1
air compressor system
supply system with compressor(s) designed to provide air for breathing or air for driving surgical tools or both
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ISO 7396-1:2002(E)
3.2
air for breathing
natural or synthetic mixture of gases, mainly composed of oxygen and nitrogen in specified proportions, with
defined limits for the concentration of contaminants, supplied by a medical gas pipeline system and intended for
administration to patients
NOTE The volume fractions of oxygen and nitrogen in air are approximately 21 % oxygen and 79 % nitrogen.
3.3
air for driving surgical tools
natural or synthetic mixture of gases, mainly composed of oxygen and nitrogen in specified proportions, with
defined limits for the concentration of contaminants, supplied by a medical gas pipeline system and intended for
driving surgical tools
NOTE The volume fractions of oxygen and nitrogen in air are approximately 21 % oxygen and 79 % nitrogen.
3.4
branch
that portion of the pipeline distribution system which supplies one or more areas on the same floor of the facility
3.5
commissioning
proof of function to verify that the agreed system specification is met and is accepted by the user or his
representative
3.6
control equipment
those items necessary to maintain the medical gas pipeline system within the specified operating parameters
EXAMPLES Pressure regulators, pressure-relief valves, alarms, sensors and manual or automatic valves.
3.7
cryogenic liquid system
supply system containing liquefied gas stored at a very low temperature
3.8
cylinder bundle
pack or pallet of cylinders linked together with a single connector for filling and emptying
3.9
diversity factor
factor which represents the maximum proportion of terminal units in a defined clinical area which will be used at the
same time, at flowrates defined in agreement with the management of the health-care facility
3.10
double-stage pipeline distribution system
pipeline distribution system in which gas is initially distributed from the supply system at a pressure higher than the
nominal distribution pressure, and is then reduced to the nominal distribution pressure by additional line pressure
regulators
NOTE This initial higher pressure is the nominal supply system pressure.
3.11
emergency clinical alarm
alarm to indicate to technical and medical staff that there is abnormal pressure within a pipeline
3.12
emergency operating alarm
alarm to indicate to technical staff that there is abnormal pressure within a pipeline
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ISO 7396-1:2002(E)
3.13
gas-specific
having characteristics which prevent connection between different gas services
3.14
gas-specific connector
screw-threaded connector of type DISS (diameter-indexed safety system) or NIST (non-interchangeable screw-
threaded), or non-interchangeable quick connector

3.15
information signal
visual indication of normal status
3.16
line pressure regulator
pressure regulator designed for a maximum inlet pressure of 3 000 kPa and intended for installation within a
medical gas pipeline system
3.17
low-pressure hose assembly
assembly consisting of a flexible hose with permanently attached gas-specific inlet and outlet connectors and
designed to conduct a medical gas at pressures less than 1 400 kPa
3.18
main line
that portion of the pipeline distribution system connecting the supply system to risers or branches, or both
3.19
manifold
device for connecting the outlet(s) of one or more cylinders or cylinder bundles of the same medical gas to the
pipeline system
3.20
manifold pressure regulator
pressure regulator designed for a maximum inlet pressure of 20 000 kPa and intended for installation within
sources of supply containing cylinders or cylinder bundles
3.21
manufacturer
natural or legal person with responsibility for the design, manufacture, packaging and labelling of a device before it
is placed on the market under his own name, regardless of whether these operations are carried out by that person
himself or on his behalf by a third party
3.22
maximum distribution pressure
pressure at any terminal unit when the pipeline system is operating at zero flow
3.23
medical gas pipeline system
complete gas pipeline system which comprises a supply system, a monitoring and alarm system and a distribution
system with terminal units at the points where medical gases or vacuum may be required
3.24
minimum distribution pressure
lowest pressure occurring at any terminal unit when the pipeline system is operating at the system design flow
3.25
nominal distribution pressure
pressure of gas which the pipeline system is intended to deliver at the terminal units
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ISO 7396-1:2002(E)
3.26
nominal supply system pressure
pressure of gas which the supply system is intended to deliver at the inlet to the line pressure regulators
3.27
non-cryogenic liquid system
supply system containing a gas stored in the liquid state under pressure at ambient temperature
3.28
non-return valve
valve which permits flow in one direction only
3.29
operating alarm
alarm to indicate to technical staff that it is necessary to replenish the gas supply or to correct a malfunction
3.30
oxygen concentrator
device which provides oxygen-enriched gas from ambient air by the extraction of nitrogen
3.31
pipeline distribution system
that part of a medical gas pipeline system linking the supply system to the terminal units
3.32
pressure regulator
device which reduces a variable inlet pressure to keep the set outlet pressure within specified limits
3.33
pressure-relief valve
device activated at a pre-set pressure value and intended to relieve excess pressure
3.34
primary supply
that portion of the supply system which supplies the pipeline distribution system
3.35
proportioning system
supply system in which gases are mixed in a specified ratio
3.36
reserve supply
that portion of the supply system which supplies the pipeline distribution system in the event of exhaustion or failure
of the primary and secondary supplies
3.37
riser
that portion of the pipeline distribution system traversing one or more floors and connecting the main line with
branch lines on various levels
3.38
secondary supply
that portion of the supply system which automatically supplies the pipeline distribution system in the event of
exhaustion or failure of the primary supply
3.39
shut-off valve
valve which prevents flow in both directions when closed
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ISO 7396-1:2002(E)
3.40
silencing
temporary stopping of an auditory alarm signal by manual action
3.41
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
3.42
single-stage pipeline distribution system
pipeline distribution system in which gas is distributed from the supply system at the nominal distribution pressure
3.43
source of supply
that portion of the supply system with associated control equipment which supplies the pipeline distribution system
3.44
supply system
system which supplies the pipeline distribution system and which includes two or more sources of supply
3.45
system design flow
flow calculated from the maximum flow requirement of the health care facility and corrected by the diversity
factor(s)
3.46
terminal unit
outlet assembly (inlet for vacuum) in a medical gas pipeline system at which the operator makes connections and
disconnections
3.47
vacuum system
supply system equipped with vacuum pumps designed to provide negative pressure
4 General requirements
4.1 Safety
Me
...