ISO 22760-9:2024

International
Standard
ISO 22760-9
First edition
Road vehicles — Dimethyl ether
2024-05
(DME) fuel system components —
Part 9:
Pressure relief device (PRD)
Véhicules routiers — Composants des systèmes de combustible
Diméthyle Ether (DME) —
Partie 9: Dispositif de limitation de pression
Reference number
© ISO 2024
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Published in Switzerland
ii
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Marking . . 2
5 Design and assembly . 2
6 Tests . 2
6.1 Applicability .2
6.2 Hydrostatic strength .3
6.3 Leakage .3
6.4 Bending moment .3
6.5 Continued operation .4
6.5.1 Test procedure.4
6.5.2 Requirements .4
6.6 Accelerated life .4
6.6.1 General .4
6.6.2 Test procedure.4
6.6.3 Accelerated-life test temperature .4
6.6.4 Requirements .5
6.7 Benchtop activation .5
6.7.1 General .5
6.7.2 Thermally-activated PRDs . .5
6.8 Thermal cycling .5
6.8.1 Test procedure.5
6.8.2 Requirements .6
6.9 Condensate corrosion resistance .6
6.9.1 Test procedure.6
6.9.2 Test solution .6
6.10 Flow capacity .6
6.10.1 General .6
6.10.2 Test procedure.6
7 Production batch inspection and acceptance testing . 7
Annex A (normative) Determination of fusible material yield temperature and PRD activation
temperature . 8
Bibliography . 9

iii
Foreword
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This document was prepared by Technical Committee ISO/TC 22, Road Vehicles, Subcommittee SC 41, Specific
aspects for gaseous fuels.
A list of all parts of the ISO 22760 series of international standards can be found on the ISO website.
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
International Standard ISO 22760-9:2024(en)
Road vehicles — Dimethyl ether (DME) fuel system
components —
Part 9:
Pressure relief device (PRD)
1 Scope
This document specifies definitions of and general requirements to a pressure relief device for limiting
internal pressure of dimethyl (DME) fuel containers intended for use on the types of motor vehicles as
defined in ISO 3833. It also provides general design principles and specifies requirements for instructions
and marking.
This document is applicable to vehicles using gaseous fuels in accordance with ISO 16861. It is not applicable
to the following:
a) fuel containers for any application other than as noted above;
b) stationary, ship, railroad vehicle or aircraft DME engine installations;
c) fuel container mounting hardware;
d) electronic fuel management.
NOTE 1 It is recognized that miscellaneous component properties not specifically addressed herein can be
examined for compliance with the criteria of any applicable part of the ISO 20760 series, including subjecting the
component to appropriate functional tests.
NOTE 2 All pressures referred to in this document are gauge pressures unless otherwise specified.
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 22760-1, Road vehicles — Dimethyl ether (DME) fuel system components — Part 1: General
requirements and definitions
ISO 22760-2, Road vehicles — Dimethyl ether (DME) fuel system components — Part 2: Performance
and general test methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 22760-1 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www. iso. org/o bp
— IEC Electropedia: available at https:// www.e lectropedia. org/

3.1
rupture pressure
activation pressure
inlet pressure specified by the pressure relief device (PRD) manufacturer, at which the PRD is designed to
activate to permit the flow to its outlet in order to discharge the fuel container pressure
3.2
activation temperature
temperature of the pressure relief device (PRD) specified by its manufacturer, at which the PRD is designed
to activate to permit the flow to its outlet in order to discharge the fuel container pressure
4 Marking
Marking of the component shall provide sufficient information to allow the following to be traced:
a) the manufacturer’s or agent’s name, trademark or symbol;
b) the model designation (pa
...